135MW CFBC Operation Manual 1(20080306)

VSLP 1×135MW POWER PLANT RAJASTHAN PROJEDCT

Client: SEPCOⅢ ELECTRIC POWER CONSTRUCTION CORPORATION

No. 26-W9-YX-01 TURBINE OPERATION RULES (A)Total 151

Pages

Operation Instruction

SEPCOIII

Drafted by:

Reviewed by:

Approved by:

Name of Change Sheet No. Time of Approval

1

2

3

TURBINE OPERATION RULES

CONTENTS

PART 1 Overview

Chapter 1 Specification of Main Equipment ………………………………………………

5

Chapter 2 Specification of Auxiliary Equipment …………………………………………

14

PART 2 Unit Start-up

Chapter 1 Cold Start of the Unit ……………………………………………….…………26

Chapter 2 Warm & Hot Start of the Unit ………………………………………….…..…38

PART 3 Unit Operation

Chapter 1 Operating Parameters of Steam Turbine ……………………………………

42

Chapter 2 Operating Modes of the Unit …………………………………………..……..47

Chapter 3 Regular Works and Requirements …………………………………..………49

PART 4 Unit Shutdown

PART 5 Treatment of Unit Accidents

Chapter 1 Treating Rules of Accidents

…………………………………………………..60

Chapter 2 Condition of Steam Turbine Tripping …………………………………...……

61

Chapter 3 Condition of Unit Fault Shutdown ……………………………………………61

Chapter 4 Condition of Emergency Shutdown………………………………….…….…62

Chapter 5 Procedure of Emergency Shutdown...…………………………….…………63

Chapter 6 Procedure of Unit Fault Shutdown ………………………………….….……63

Chapter 7 Decreasing of Vacuum …………………………………………………..……64

Chapter 8 Water Hammer of Steam Turbine ……………………………………………65

Chapter 9 Increasing of Axial Displacement ……………………………………....……66

Chapter 10 Steam Turbine Oil System Catching Fire ……………………………....…67

Chapter 11 Abnormity of Steam Conditions ………………………………………….…68

Chapter 12 DEH Failure …………………………………………………………….……71

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Chapter 13 Abnormity of Steam Turbine Lubricating Oil System ……………………71

Chapter 14 Abnormal Vibration of the Unit ……………………………………….……75

Chapter 15 Generator parallels off, while turbine does not trip ……………..….……77

Chapter 16 Generator parallels off, and turbine trips …………………………………77

Chapter 17 Turbine trips, while the generator does not parallel off …………………78

Chapter 18 Failure of Thermodynamic Power Supply …………………………………78

Chapter 19 High Bearing Temperature of Turbine-generator Unit ……………………

79

Chapter 20 Burning out of Turbine-generator Bearing Bush ……………………….…79

Chapter 21 Steam Turbine Shaft Bending ………………………………………………80

Chapter 22 Steam turbine Overspeed ………………………………………………..…82

Chapter 23 Feed water pump set outlet check valve is untight and rotates

reversely.83

Chapter 24 Turbine-generator unit operates at abnormal frequency …………………

83

Chapter 25 Boiler Fire Extinction …………………………………………………………

84

Chapter 26 Treatment of Accidents & Abnormity of the Motor ………………………..85

PART 6 Auxiliary Equipment & Common Service System

Chapter 1 General Operating Rules of Auxiliary Equipment……………………..……

89

Chapter 2 Industrial Water System……………………………………………………….92

Chapter 3 Oil Purification System of Steam Turbine……………………………………

94

Chapter 4 Lubricating Oil System of Steam Turbine ……………………………………

98

Chapter 5 Circulating Water System ……………………………………………..…….102

Chapter 6 Shaft Sealing and Vacuum System of Steam Turbine ……………..

…….108

Chapter 7 Condensate Water System ………………………………………..………..111

Chapter 8 Feed Water Deaerating System ……………………………………..…….117

Chapter 9 DEH System …………………………………………………………..……..131

Chapter 10 Bypass System ……………………………………………………..………136

Chapter 11 Turbine Proper Water Drain System ……………………………..………138

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Chapter 12 Quick Cooling System of Steam Turbine ………………………..………139

Chapter 13Air Cooling System …………………………………..………143

Appendix 1: Comparison Table of the Temperature & Pressure of Saturated Water &

Steam ………………………………………………………………………………….......147

PART 1: Overview

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Chapter 1 Specification of Main Equipment

1.1 Specification of steam turbine equipment

Model: N135-13.2/535/535

Type: super-high pressure, primary reheating, double cylinder, double-flow, single shaft,

extraction and condensing steam.

Rated power: 135MW

Initial steam pressure: 13.24Mpa (a)

Initial steam temperature: 535℃

Reheat steam temperature: 535℃

Exhaust pressure: 5.4kPa (a)

Rated speed: 3,000r/min

Rotating direction: clockwise (as viewed from the governor side to generator)

Manufactured by: Shanghai Turbine Co., Ltd.

1.2 Main technique parameters

Max power: 146.822MW

Rated power: 135MW

Rated pressure of the steam before initial steam stop valve: 13.24mpa (a)

Rated temperature of the steam before initial steam stop valve: 535 ℃

Rated pressure of the steam before reheat steam valve: 2.238mpa (a)

Rated temperature of the steam before reheat steam valve: 535℃

Rated cooling water temperature: 24℃

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Rated backpressure:5.4kpa (a)

Rated speed: 3,000 rpm

Feed water temperature under rated condition: 244.4℃

Max back pressure at which the unit is permitted to operate: 18.6kpa (a)

Regeneration stages: 2 HP heaters, 4 LP heaters & 1 deaerator

Length of the last blade of LP cylinder: 660mm

Critical speed of shafting: 1850r/min for HP & MP rotor

2116r/min for LP rotor

1290r/min for generator rotor

Stages of flow path: total 39 stages:

HP cylinder: 1 governing stage + 8 pressure stages

MP cylinder: 10pressure stages

LP cylinder: 2×6 pressure stages

1.3 Description of turbine characteristics

1.3.1 This unit can carry the base load of power network, as well as can be used as two-shift or

peak regulation unit.

1.3.2 This unit’s operating time at no load when rejecting load must not exceed 15 mins.

1.3.3 This unit’s operating time without steam must not exceed 1 min.

1.3.4 This unit’s idle time with full vacuum after trip is about 45 mins and that without vacuum is

about 15 mins.

1.3.5 This unit’s blades can run safely at the grid frequency of 47.5~51.5hz for long; the unit’s

characteristics also meet the requirements as follows:

Frequency (Hz)Permitted Operating Time

Accumulated (min) Every Time (Sec)

52.5 >5 >5

52.0 >30 >30

47.5~51.5 Continuous Operation

47 >60 >60

46.5 >10 >10

46 >2 >2

1.3.6 The peak to peak vibration amplitude measured near the bearing journal of turbine shall be

≤ 0.075mm during normal operation, which shall not exceed 0.25mm as critical speed passing in

speed rise;

1.3.7 The power load of the unit is permitted to reach 135MW when the HP heaters are cleared;

1.3.8 The unit is permitted to run continuously with low load when the exhaust pressure of turbine

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increases to 0.0146Mpa (a). The alarm back pressure of turbine is 16.9kPa (a) and trip back

pressure is 20.3kPa (a).

1.3.9 The unit is permitted to run for long when the exhaust temperature of steam turbine is less

than 79 . The ℃ max temperature at which exhaust is permitted to operate is 120 .℃

1.3.10 Permitted load variation rate of unit is:

1.3.10.1 From 100% to 50% MCR 5%/min

1.3.10.2 From 50% to 20% MCR and from 20% to 50% MCR 3%/min

1.3.10.3 Below 20%MCR 2%/min

1.3.11 The pressure after the governing stage must not exceed 10.34Mpa (a) at different working

conditions.

1.4 General description of steam turbine

1.4.1 Brief introduction of steam turbine proper

1.4.1.1 Steam turbine type is: super-high pressure, primary reheating, double-flow and single

shaft arrangement, reaction extraction and condensing type, which characteristics include:

combination of HP and IP cylinder, reverse arrangement of through-flow parts, inlets of initial

steam and reheat steam centered on the middle part of HP & MP cylinder and radial diffusion

double-flow type of LP cylinder.

This unit’s shafting is supported by three points: HP & MP rotor connected with LP rotor by rigid

coupling while the LP rotor connected with the generator rotor by semi-flexible coupling,

generator rotor expands and contracts forwards and backwards with the thrusting bearing in

middle bearing pedestal as the dead point, and HP & MP cylinder expands forwards based on the

cross point of longitudinal and traverse key of the middle bearing pedestal. There is an absolute

expansion indicator on the front bearing frame with total cylinder expansion of 20-22mm. and the

LP outer cylinder expands backward with the cross point of the longitudinal and traverse key in

the front of the LP outer cylinder as the dead point.

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HP Governing Valves Layout

Generator End

Upper Half

Lower Half

Governing Valve End

Main Stop Valve (L) Main Stop Valve (R)


The turbine unit is 14 meters long in total and arranged on the 9m operation floor, with a

combination of HP initial steam stop valve and HP governing valve mounted on both sides in the

front which is supported on the holder of main stop valve, 4 flexible HP steam inlet pipes

connected with the 4 governing valves and the HP cylinder’s upper and lower steam inlets

respectively, and governing valve controlled by oil servo-motor.

The high pressure nozzle section consists of four groups of nozzle segments, The unit can reach

rated power by 3 valves opening fully and the fourth group provides guarantee for the availability

of rated power in summer and at low parameters.

HP & MP cylinder is double-floor cylinder with 1 governing stage and 8 pressure stages in the HP

part. There is a section of steam extraction led to HP heater #1 after stage 7, and steam

exhausted by HP flows through lower cylinder’s exhaust port and HP exhaust check valve to the

reheater, a portion of which is led to HP heater #2 as regenerative extraction.

The reheated steam flows to MP part via MP combined valve through two rigid steam inlet pipes.

There are 10 pressure stages in MP part with a third stage extraction to deaerator after stage6

and a fourth extraction led to LP heater #4 after stage 8.

For MP exhaust part, the upper half is designed to exhaust steam upwards that flows into LP

cylinder through 2 flexible cross over pipes with compensation capacity; the lower half has a fifth

extraction led to LP heater #5.

The LP cylinder is double flow and has 2×6 stages, there are a 6th and 7th extraction openings set

in LP cylinder that lead extraction to LP heater #6 and LP heater #7 (built-in type) inside the

condenser respectively and led out after the stage 3 and stage 6 respectively.

This steam turbine has three bearing pedestals in all, in which 3 turbine journal bearings, 1

generator front bearing and 1 thrust bearing are mounted. All bearing pedestals are floor

mounted. Besides journal bearing in bearing pedestal #1, there are also main governing set,

including main oil pump and emergency governor etc.

Two MP combined valves are arranged on the left and right side in the middle of the unit

respectively, which may move freely on its bearing surface with expansion of the turbine, the MP

governing valve only operates for regulation at below 30% load and opens fully not to take part in

regulation in the case where the load is more than 30%.

The rotary equipment of steam turbine rotor is mounted on the back bearing pedestal and driven

by motor after speed reduction, rotor turning gear speed rotation is 7~8r/min, each bearing is

equipped with HP jacking oil system in order to lower the start-up power of rotary equipment and

protect all bearings from damage.

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LP cylinder is equipped with atomizing nozzle type low-load spray regulator inside that may

operate to spray automatically in the case where the LP cylinder exhaust temperature is higher

than 80℃ so as to ensure normal operation of the unit.

1.4.1.2 Sliding key system

The sliding key system is the supporting and locating system of stator part, the steam turbine

proper supporting and locating mode is: front frame, middle frame and rear frame and exhaust

hood frame are fastened on the foundation by means of foundation bolts and back grouting and

are equipped with front bearing pedestal, middle bearing pedestal, rear bearing pedestal and LP

outer cylinder thereon respectively. Longitudinal keys are arranged on the front frame along the

center axis, the front bearing pedestal can move on its frame along the axis. HP & MP outer

cylinder upper claws are supported on the front and middle bearing pedestal, the lower claw’s

transverse keys connect with the front and middle bearing pedestal, besides longitudinal keys,

there are also transverse keys on some position of the middle frame, and the cross point of

longitudinal and transverse key is the dead point of HP & MP stator part, the front bearing

pedestal HP and MP cylinder and middle bearing pedestal take this as the dead point to perform

axial expansion and contraction. There is a vertical key mounted on both upside and downside of

both ends of HP & MP outer cylinder with key way plate fixed on the neighboring bearing pedestal

for the purpose of smooth expansion and contraction and keeping cylinder center aligning.

1.4.1.3 Thrust bearing

The unit adopts the Michell thrust bearing. The thrust collar integrates with steam turbine, and

both its front and back sides are mounted with positive and negative thrust bearing pads with 12

pieces laid on the whole circle of each. And each pad is equipped with a RTD temperature

measuring device for measuring its metal temperature. The back of thrust bearing pad rests on

erection loop, and erection loop leans against the spheric seating, which gives self alignment

effect. Positive or negative thrust of steam turbine bearing operates on the operating pad or non-

operating pad separately, and the bearing displacement on thrust pad shall not be more than

0.4mm. The lubricating oil enters between thrust collar and thrust pad via oil inlets on both sides

for lubricating, and then flows out from thrust collar outer side, the return oil escapes from the top,

and there are two return oil adjusting screws mounted on return oil outlet, which can adjust the oil

return quantity to control return oil temperature.

1.4.1.4 Journal bearing

This unit adopts elliptic type journal bearing, which consists of a bearing bush cast with Babbitt

metal, bearing shell and spheric seating. The bearing is made into upper and lower, two halves

that are fixed and positioned by screws and taper pins, the bearing case matches with spheric

seating on spherical surface, which gives self alignment effect, and there are four set pieces on

the spheric seating for the use of adjustment. Lubricating oil flows into bearing through a hole at

lower part of bearing and then flows into bearing pedestal via the bearing end. There is a

platinum resistor mounted on the bearing bush that can measure the bearing metal temperature,

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there is oil from return chute in the bore of locating pin in upper bearing half, which temperature

can be measured as that of bearing return oil, and there is HP jacking oil hold at the bottom of

bearing bush.

1.4.1.5 Shafting

The steam turbine proper shafting consists of HP & MP rotor and LP rotor. Connection between

HP & MP rotor and LP rotor relies on the rigid coupling integrated with main shaft forging, and the

shims in between two halves of coupling are connected with screws. As configured for the

purpose of meeting the requirement of rotor center aligning in assembly, in such a case, the

center on both ends of coupling must keep correct and concordant in assembly so as to allow the

rotor center line to become smooth and continuous curve in operation. The rigid coupling is very

sensitive to the bearing load distribution because of high rigidity, thus its requirements for the

assembly technology and shafting aligning are much higher, but it has such advantages as high

strength, short rotor length, easy processing and reliable operation.

Semiflexible coupling is used in between LP rotor and generator rotor, such coupling has a

corrugated pipe joint on the end coupling connecting with generator rotor, which has certain

flexibility, and connects with an minor axis on the other end coupling, and the minor axis covers

the generator rotor to transmit the torque by means of interference and key, such semiflexible

coupling may allow the unit safety operation not to be affected by slight change in the steam

turbine and generator center in installation and operation.

1.4.2 Technical specifications of governing system

1.4.2.1 The governing system is able to keep idle running of steam turbine at rated steam inlet

condition, rated vacuum and full open main stop valve, with speed oscillation value >P 6r/min.

1.4.2.2 The governing system is able to guarantee stable parallel operation of steam turbine and

other units.

1.4.2.3 The governing system is able to control and guarantee the need of steam turbine

incorporating into network and adaptation to changes in speed and load.

1.4.2.4 For this unit operating at rated steam conditions and rated speed, the governing system is

able to control the turbine speed not to result in the trip of emergency governor as the unit rejects

load.

1.4.3 Technical specifications of steam turbine control system

1.4.3.1 This unit has three sets of governors:

Emergency governor handle to be tripped by operator manually for emergency;

Mechanical emergency governor to trip at overspeed;

Four governor solenoid valves controlled by ETS, which receive the governing signal of

important parameters of steam turbine.

1.4.3.2 System function:

1.4.3.2.1 Governing function:

The governor valve will trip to shut down the turbine for emergency trip as the following

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parameter exceeds the specified value.

a. Speed rises to 110% of rated speed;

b. Axial displacement exceeds ±1.2mm;

c. HP & MP cylinder differential expansion exceeds +8.0 or -3.0mm;

d. LP cylinder differential expansion reaches +7.5mm;

e. Lubricating oil pressure is lower than 0.06Mpa;

f. Back pressure of the condenser is lower than 20.3kPa;

g. Peak to peak vibration amplitude of the rotor is ≥ 0.254mm;

h. Metal temperature of # bearing 1-3 reaches 112℃, the metal temperature of bearing #4 and #5

reaches 80℃ or the temperature of thrust bearing reaches 107℃;

i. EH oil pressure decreases to 9.31Mpa;

j. Power failure to DEH system;

k. Exhaust temperature of LP cylinder reaches 121℃;

l. The oil level of the main oil tank is lower than 1245mm;

m. MFT of the boiler;

n. Main protection of the generator operates.

1.4.3.2.2 Oil injection test function

1.4.3.2.3 Emergency governor test function

1.4.3.2.4 Steam turbine reset function

1.5 Heat calculation data of the steam turbine

Name UnitRated

conditions THATMCR VWO

Cutting off all HP Heaters

Generator end power kW 135,029 135,101 145,005 135,043

Total steam inlet flow of steam turbine

t/h 407.502 410.107 440.000 368.560

Initial steam pressure /temperature

MPa/℃ 13.24/535 13.24/535 13.24/535 13.24/535

HP cylinder exhaust pressure MPa 2.533 2.534 2.724 2.677

HP cylinder exhaust temperature

℃ 312.1 311.9 317.8 321.6

Reheat steam flow t/h 335.397 335.701 360.968 354.820

Reheat steam pressure /temperature

MPa/℃ 2.33/537 2.332/537 2.506/537 2.463/537

Back pressure kPa 5.4 5.4 5.4 5.4

Cooling water temperature ℃ 32.1 32.1 32.1 32.1

Feed water temperature ℃ 244.4 244.5 248.8 171.4

Make-up water flow kg/h 0 3 0 0

Flow into condenser t/h 284.081 282.090 303.577 298.143

Heat rate kJ/kWh 8,402.9 8,363.9 8,355.9 8,630.8

Steam rate kg/kWh 3.018 3.036 3.034 2.729

No.1 extraction steam condition MPa/℃ 3.552/354.9 3.56/354.9 3.832/361.4

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Name UnitRated

conditions THATMCR VWO

Cutting off all HP Heaters

No.1 extraction flow t/h 22.14 23.051 24.681

No.2 extraction steam condition MPa/℃ 2.457/312.3 2.458/312.1 2.642/317.9

No.2 extraction flow t/h 36.871 38.251 40.589

No.3 extraction steam condition MPa/℃ 0.73/377.9 0.729/377.6 0.784/377.5 0.769/377.1

No.3 extraction flow t/h 8.066 8.47 9.124 9.863

No.4 extraction steam condition MPa/℃ 0.451/315.8 0.45/315.4 0.484/315.3 0.475/315


No.5 extraction steam condition MPa/℃ 0.251/248.4 0.25/247.8 0.269/247.8 0.264/247.5


No.6 extraction steam condition MPa 0.067 0.0665 0.0718 0.0705


No.7 extraction steam condition MPa 0.0143 0.0142 0.0152 0.015


Note: Turbine Heat Acceptance condition (THA): means the condition in which the unit can

operate safely and continuously with generator’s net output power of 135MW when the turbine is

under rated initial steam and reheat steam conditions, back pressure is 5.4kP, make-up water

percentage is 0%, and regenerative system is put into operation all normally and generator’s

efficiency is 98.4％, which heat rate is not more than the acceptance value of 8,402.9kJ/kWh.

Turbine maximum continue rate (TMCR): means the condition in which the unit can operate

safely and output maximum power when the turbine is under rated initial steam and reheat steam

conditions, back pressure is 5.4kP, make-up water percentage is 3%, and regenerative system is

put into operation all normally and generator’s efficiency is 98.4％.

Valve Wide Open condition (VWO): means the condition in which the turbine’s steam inlet flow is

440t/h when the turbine’s governing valves are wide open and the other conditions is the same

with 2.1.1, which output value is 145.822MW. This condition corresponds to the Boiler Maximum

Continue Rate (BMCR).

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Chapter 2 Specification of Auxiliary Equipment

2.1 Specification of heater

2.1.1 Specification of HP heater

Item Unit HP heater #2 HP heater #1

Model JG-530-2-00CK JG-530-1-00CK

Design pressure of shell side Mpa 3.0 4.5

Design temperature of shell side ℃ 350/250 390/260

Design pressure of tube side Mpa 20 20

Design temperature of tube side ℃ 250 260

Feed-water Inlet temperature ℃ 172.2 223.9

Feed-water outlet temperature ℃ 223.9 248.8

Working pressure MpaTube side 18

Shell side 2.64

Tube side 18

Shell side 3.8318

Working temperature ℃ Shell side 317.9/180 Shell side 361.4/247.8

Manufacturer Qingdao Qingli Boiler Auxiliary Equipment Co., Ltd.

2.1.2 Specification of LP heater

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Item Unit LP heater #7 LP heater # 6 LP heater # 5 LP heater # 4

Model JD-220-1-1 JD-300-1-3 JD-300-1-2 JD-300-1-1

Heating surface area M2 200 300 300 300

Design pressure of tube side Mpa 2.5 2.5 2.5 2.5

Design temperature of tube

side℃ 100 100 150 180

Design pressure of shell side Mpa 0.05 0.4 0.4 0.5

Design temperature of tube

side℃ 100 100 260 350

Working pressure of tube side Mpa 1.724 1.724 1.724 1.724

Working pressure of shell side Mpa 0.0152 0.07257 0.2693 0.454

Working temperature of tube

side℃ 55 69.45 109.05 138.25

Working temperature of shell

side℃ 55 90.63 129.9 150.6

Manufacturer Shanghai Power Equipment Co., Ltd.

2.1.3 Specification of deaerator and deaerated water tank

2.1.3.1 Specification of deaerator

Class Class I Test pressure 1.374MPa

Model GC-514 Pressure drop of nozzle 0.0588MPa

Design pressure 0.88Mpa (g) Opening pressure of safety valve 0.85MPa

Design temperature 380℃ Operating modeSliding pressure

operation

Max working pressure 0.78Mpa (a)Corrosion allowance

(tank /deaerator)1.6/2.5mm

Rated output 514t/h Oxygen content of outlet water ≤7PPb

Inlet water

temperature147℃ Outlet water temperature 169.3℃

Manufacturer Qingdao Qingli Boiler Auxiliary Equipment Co., Ltd.

2.1.3.2 Specification of dearated water tank

Class Class I Opening pressure of safety valve 0.85MPa

Type GS-120 Test pressure 1.374MPa

Design pressure 0.88Mpa (g) Effective volume 120m3

Design temperature 380℃ Total volume 140m3

Max working pressure 0.68MPaCorrosion allowance

(tank /deaerator)1.6/2.5mm

Manufacturer Qingdao Qingli Boiler Auxiliary Equipment Ltd.

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2.2 Specification of feed-water pump

2.2.1 Feed-water pump and booster pump

Equipment parameter Unit Feed-water pump Booster pump

Model FK5G32 QG500-80

Number of stages stage 5 1

Inlet water flow m3/h 533.3 533.3

Outlet water flow m3/h 497.8 533.3

Lift m 1771.9 79.6

Inlet water pressure MPa 1.48 0.6837

Outlet water pressure MPa 19.18 1.48

Shaft power kW 2733.9 128.7

Rotating speed r/min 4686 2982

Working temperature ℃ 166.7 166.7

Medium density kg/m3 900.59 900.59

Intermediate bleed-off pressure (stage 2) MPa 8

Intermediate bleed-off flow m3/h 35.5

Guarantee efficiency % 81.32 80.84

ManufacturerShanghai Power Equipment

Maintenance Works Co., Ltd.

2.2.2 Specification of feed-water pump motor

2.2.2.1 Specification of feed-water pump motor

Item Unit Specification

Model YKOS3700-2

Rated power kW 3,700

Rated voltage V 6,600

Rated current A 370

Rated speed r/min 2,982

Rated frequency Hz 50

Connection type of stator Y

Insulation class Class F

Power factor COSφ 0.9

Cooling mode Air-cooled

Temperature rise ℃ 80

Manufacturer Shanghai Motor Co., Ltd.

2.2.2.2 Specification of air cooler of feed-water pump motor


Capacity of cooler kW 160

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Operating water flow t/h 60

Circuit of cooling water Group 2

Air pressure drop kPa 0.32

Working water pressure MPa 0.2-0.4

Max permitted water pressure MPa 0.5

2.2.3 Specification of hydraulic coupling

2.2.3.1 Parameters of hydraulic coupling


Model R17K.2-E

Motor speed r/min 2,986

Output speed r/min 4,783

Max output power kW 3,000

Slip % ≤3

Scope of speed governing % 25-100

Efficiency % 94.7

Capacity of oil tank m3 0.85

Manufacturer Germany VOITH

2.2.3.2 Auxiliary equipment of coupling

Item Unit Auxiliary oil pumpWorking oil

cooler

Lubricating oil

cooler

Model CB-B125 LY54 LY16

Oil flow m3/h 7.5 30 17

Pressure MPa 0.25

Cooling surface area m2 54 16

Cooling water flow m3/h 120 27

2.3 Circulating water system

2.3.1 Specification of circulating water pump

Specification of circulating water pump

(double pumps in parallel operation)

Specification of circulating water pump

motor

Model 44LBXA-23 Model YLKK900-10

Shaft power 770.3 kW Voltage 6,600V

Lift 23m Current 98A

Rotating speed 595 r/min Power 900kW

Flow 10,728t/h Power factor 0.86

Efficiency 87.2% Rotating speed 595r/min

Cooling water of bearing 90m3/h, 0.3MPa

Mini submergence 3m

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Manufactured byChangsha Water

Pump WorksManufactured by

Shangyang Electric

Machine Co., Ltd.

2.3.2 Automatic back washing strainerItem Unit Specification

Model ASCS300

Working pressure MPa 0.3

Max pressure MPa 0.6

Inlet & outlet diameter mm φ300

Manufactured by Shanghai Power Equipment Research Institute

2.3.3 Circulating water booster pump

Specification of circulating water booster pumpSpecification of circulating water

booster pump motor

Model 10Sh-9A Model Y250M-4

Shaft power 40 kW Voltage 415 V

Lift 30 m Current A

Rotating speed 1,480r/min Power 55 kW

Flow 420 t/h Power factor

Efficiency 80% Rotating speed 1,480 r/min

Manufactured byShijiazhuang Kingda Pump

Co, Ltd.Manufactured by

Xi’an Motor

Works

2.3.4 Indoor circulating sump pit blowdown pumpSpecification of indoor circulating sump pit

blowdown pump

Specification of indoor circulating

sump pit blowdown pump motor

Model 40PV-SP Model Y112M-2

Shaft power 3.1kW Voltage 415V

Lift 15m Current A

Rotating speed 1,800 rpm Power 4 kW

Flow 25t/h Power factor

Efficiency 34% Rotating speed 2900 r/min

Manufactured byShijiazhuang Kingda Pump

Co., Ltd.Manufactured by

Xi’an Motor

Works

2.3.5 Trash remover of circulating water pump house

Specification of trash remover of circulating water

pump house

Specification of trash remover motor

of circulating water pump house

Model ZSB-3500 Model BWD5-87-5.5

Water head in operation start 300mm

Max design water head 600mm Voltage 415V

Mesh size 3.5×53 mm Current A

Travelling speed of scrubbing

brush6~7 m/min Power 5.5 kW

Total Number of scrubbing brush 4 Power factor

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Rotating speed of round brush 20.33 r/min Rotating speed 87 rpm

Manufactured byJiangsu Yihaun

Group Co., Ltd.Manufactured by

2.4 Shaft seal system

2.4.1 Shaft seal

HP & MP seal ring are high & low-tooth labyrinth structure and LP seal ring is flat tooth structure;

HP & MP cylinder diaphragm seal is embedded seal, the sealing strip is riveted into the

diaphragm with fillet; the seal ring of LP diaphragm seal is mounted in the septalium and fixed

with spring leaf.

2.4.2 Shaft seal heater


Model JQ-50-1

Heating surface area m2 50

Design flow of main

condensate flowm3/h Total flow, 300 minimum

Design pressure MPa Tube side 3.1, shell side 0.1

Working pressure MPa Tube side 2.00

Test pressure MPa Tube side 3.9, shell side 0.125

Design temperature ℃ Tube side 100, shell side 100

Working temperature ℃ Tube side 60, shell side 100

Net weight t 2.23

2.4.3 Shaft seal fan:

Specification of shaft seal fan Specification of the motor

Model AZY-09.32-020.0-01 Model 132S

Full pressure 9.32kPa Power 7.5kW

Speed 2,900r/min Speed 2,900r/min

Flow 20m3/min Voltage 415V

Manufactured byZhejiang Yuyao Blower

PlantManufactured by

Wannan Electric

Machine Co., Ltd.

2.5 Condensate and steam extraction system

2.5.1 Specification of condenser

Model N-9000Cooling water

temperature32.5℃

TypeSingle shell, bisection, double

passes and surface typeNumber of pass 2

Total active cooling

surface area9,000 m2

Velocity in cooling

water pipe2m/s

Design pressure of tube 0.25MPa Outer diameter of φ25mm

- 18 -


side cooling water pipe

Design pressure of shell

side0.1MPa/Vac

Water resistance

of condenser<45kPa

Test pressure of tube side 0.375MPaTotal number of

copper tube12,760

Cooling water flow 20,200m3/h Net weight 211t

Manufactured byShanghai Power Equipment

Co., Ltd.

2.5.2 Specification of condensate pump

Specification of condensate pump Specification of the motor

Model 7LDTNB-6PJS Model YLKK400-4

Flow 350m3/h Power 280kW

Lift 190m Voltage 6,600V

Npsh 2.2m Current 31A

Shaft power 223kW Rotating speed 1,487r/min

Rotating speed 1,487r/min Insulation class F

Manufactured byShenyang Pump Co.,

Ltd.Manufactured by

Shenyang Electric

Machine Works

2.5.3 Vacuum pump

Specification of vacuum pumpSpecification of the

motor

Specification of

vacuum pump cooler

Model: 2BW4 253-0EK4 Model: Y315M-8 Model: M16

Min. suction pressure (min. vacuum degree):

3.3kpa (a)Voltage: 415V

Heat exchange surface

area: 9m2

Pumping capacity ≥44kg/h (as inlet pressure

of 8.83kpa and cooling water temperature of

32.5 )℃

Power: 75kW

Cooling water inlet

temperature:

38℃ max

Rotating speed:740 r/minRotating speed:

740r/min

Working water flow:

10.2m3/h

Shaft power: 54kw max; 42kw at 8.83kp;

46.5kw at 11.8kpaRated current: A

Working water inlet

temperature: 44.5℃,

outlet pressure: 39.5℃

Make-up water flow of separator: 0.5m3/h,

temperature<50℃Insulation class: F

Cooling water flow:

20~22 m3/h

Manufactured by: Foshang Pump WorksManufactured by:

Xiangtan Motor Works

Manufactured by: AF

LAVAL

- 19 -


2.5.4 LP heater drain water pump

Specification of LP heater drain water pump Specification of the motor

Model:150NW55-190－000 Model: Y280S-2

Flow: 55 m3/h Power: 75 kW

Lift:190m Voltage: 415 V

Rotating speed: 2,970 r/min Current: A

NPSH: 1.8m Rotating speed: 2,970 r/min

Efficiency: 61％ Insulation class: F

Manufactured by: Shanghai Hualian Pump Co.,

Ltd.

Manufactured by: Jiamusi Electric Machine

Works

2.6 Specification of steam turbine lubricating oil system

2.6.1 Main oil tank

Dimension (length×diameter) 5,810×3,020 mm

Maximum volume 40 m3

Working volume 24 m3

Operating oil level 1,808mm

Maximum oil level 2,616mm

Minimum oil level 1,245mm

Suction level of oil injector 1,045mm

2.6.2 Oil cooler

Model GX-64P

Cooling surface area 240m2

Working temperature Above 0℃

Flow 80l/min

Test pressure 21bar

Empty weight 1,803kg

All-up weight 2,283kg

Manufactured by SWEP PHE AB

2.6.3 Main oil pump

Type Centrifugal type

Capacity 4.5m3/min

Outlet pressure 1.18Mpa (g)

Rotating speed 3,000r/min

2.6.4 Oil injector

Oil injector I II

Outlet oil pressure 0.098Mpa (g) 0.197Mpa (g)

- 20 -


2.6.4 Jacking oil pump

Specification of jacking oil pump Specification of the motor

Model: 25SCY14-1B Model: Y160L

Flow: 25L/min Voltage: 415V

Outlet pressure: 32.0MPa Power: 15kW

Rotating speed:1,500r/min Rotating speed:1,500r/min

Operating value of overflow valve: 12.25 Mpa (g) Insulation class: B

Manufactured by: Shanghai HP Oil Pump Works Manufactured by: Shanghai WUYI Electric

Company

2.6.5 AC lubricating oil pump

Specification of AC lubricating oil pump Specification of the motor

Model: YS150-50BⅡ Model: YB180M-2

Water head: 36m Power: 22kW

Flow: 133m3/h Voltage: 415V

Rotating speed: 2950r/min Current: 42.2A

NPSH: 4.5m Insulation class: F

Manufactured by: Shanghai Pump WorksManufactured by Shanghai Wuyi Electric

Machine Works

2.6.6 DC lubricating oil pump

Specification of DC lubricating oil pump Specification of the motor

Model: YSI50-50BⅡ Model: Z2-62

Lift: 36m Power: 22kW

Flow:133m3/min Rotating speed: 3,000r/min

Rotating speed: 2,950r/min Current: 114.2A

NPSH: 4.5m Insulation class: B

Manufactured by: Shanghai Pump WorksManufactured by Hangzhou Hengli Electric

Machine Manufactory

2.6.7 Exhaust blower of main oil tank

Specification of the exhaust blower Specification of the motor

Model: GXP-Ⅱ－155 Model: Y100L-2

Air flow: 0.32m3/s Power: 3kW

Total pressure: 4.5kPa Voltage: 415V

Matched power: 3kW Current: 6.4A

Rotating speed: 2,960 r/min Insulation class: B

Manufactured by: Mudanjiang Aidi Electric Power Manufactured by: Hebei Chengde

- 21 -


Technology Co., Ltd. Electric Machine Works

2.6.8 Specification of the oil purifying equipment

Model: HCP100 380 50 AS-SD

Power: 3.0kW

Voltage: 415V

Max current: 8.2A

Flow: 100l/min

System working pressure: <1.0MPa

Operating temperature: -10~60℃

Max viscosity of treating medium: ≤46cSt

Water discharge: About 5 L/time

Manufacturer: PaLL Filter Ltd.

2.6.9Turning gear

Model horizontal

Motor capacity 37 kW

Rated voltage AC 415V

Motor speed 1,480 r/min

Turning speed 7~8 r/min

2.7 Specification of sponge ball cleaning pump

Item Sponge ball cleaning pump

Pump

Model 125JQ-15

Shaft power 11 kW

Lift 15 mH2O

Flow 90 t/h

Rotating speed 1,460 r/min

Manufacturer Qingdao Huatai Electric Equipment Co., Ltd,

Motor

Model Y160M-4

Voltage 415 V

Current 22.6A

Power 11 kW

Rotating speed 1,460 r/min

Manufacturer Rongchen Daxing Electric Machine Works

2.8 EH oil system

Specification of EH oil pump Specification of the motor Specification of oil cooler

Code: 029-09941-5 Model: Y200L-4 B35 Model: GL02

- 22 -


Model: PV29 2R50 COO Power: 30kW Working pressure: 1.6MPa

Outlet pressure: 13.7MPa Voltage: 415V Working temperature:

≤100℃

Setting value of overflow

valve:16.2MPa

Current: 56.8A Cooling surface area: 2.1m2

Rotating speed: 1,470r/min Manufactured by: Shanghai

Lubricating Equipment Plant

Manufactured by Shanghai Wuyi

Electric Machine Works

2.9 Specification of rapid cooling device


Model YQL- 150Ⅱ

Rated air flow m3/min 40

Voltage V 415

Power kW 150

Outlet temperature ℃ 400

Working pressure MPa 0.8

Dimension 2500×1800×1900

Manufactured by Jiangsu Yangzhong Huangneng Electric Power Equipment Plant

2.10 Specification of bypass system

Item UnitPressure reducing

valve of HP bypass

Attemperating

water valve of

HP bypass

Pressure reducing

valve of LP bypass

Attemperating

water valve of

LP bypass

Rated flow t/h 308 50.42 358 109.3

Design inlet pressure MPa 14.29 21.2 3.03 2.5

Design outlet pressure MPa 3.03 21.2 1.0 2.5

Design inlet

temperature℃ 545 200 545 80

Design outlet

temperature℃ 337 200 160 80

Inlet working pressure MPa 13.73 17.3 2.331 1.85

Outlet working

pressureMPa 2.534 7.3 0.6 1.48

Inlet working

temperature ℃ 537 166.7 537 43.4

Outlet working

temperature℃ 312.3 166.7 160 43.4

Manufactured by Shanghai CCI Power Control Equipment Co., Ltd.

The two-stage series connection bypass system is adopted, in which, the flow capacity of HP

- 23 -


pass is considered as 70% of steam flow under VWO condition and the flow capacity of LP

bypass is considered as the sum of HP bypass flow plus HP bypass attemperating water flow.

2.11 Specification of air cylinder:

Design pressure: 1.0 MPa

Design temperature: 100℃

Maximum working pressure: 0.98 MPa

Working temperature: normal temperature

Working medium : air

Test pressure: 1.25 MPa

Volume: 1.0 m3

PART 2 Unit Start-up

- 24 -


Chapter 1 Cold Start of the Unit

1.1 General rules of start-up

1.1.1 Division of the start-up state

According to the inner wall temperature in upper half where HP inner cylinder governing stage is

located, the start-up state of steam turbine is divided into:

a. Cold state:below 150℃

b. Warm state: 150~300℃

c. Hot state: 300~400℃

d. Very hot state: above 400℃

1.1.2 The turbine is not permitted to start in any case as follows:

1) Eccentricity of rotor exceeds original value by 30m (original value is measured after

installation or overhaul).

2) Emergency governor operates abnormally or overspeed protection fails in operating reliably.

3) One of HP & MP automatic main stop valve, speed governing valve, steam extraction check

valve or HP exhaust check valve was choked and fails in closing tightly.

4) Emergency governor operates as a result of turbine governing system failure in maintaining

idle running or controlling the rotation speed after load rejection.

5) There is clear friction sound occurred to the rotating parts of turbine and generator or the

current of turning gear increases obviously and oscillates greatly.

6) The temperature difference between upper and lower part of cylinder exceeds 50 .℃

7) The differential expansion of turbine reaches limit value.

8) The monitoring function of main parameters fails (including rotating speed, vibration, axial

displacement, differential expansion, lubricating oil pressure, lubricating oil temperature, EH oil

pressure, bearing metal temperature, bearing return oil temperature, thrust bearing pad

- 25 -


temperature, pressure and temperature of initial steam and reheat steam, vacuum of condenser,

pressure switch of control system, metal temperature of main cylinders and etc.).

9) Any safety protection or system fails or unit protection operating values are not in accordance

with stipulation.

10) Any one of the following equipment has fault or the corresponding interlock protection test is

unqualified: starting oil pump, AC (DC) lubricating oil pump, jacking oil pump, turning gear, EH oil

pump.

11) The oil level of main oil tank and EH oil tank is lower than the limit value or the oil quality and

cleanliness are unqualified. Lubricating oil inlet temperature is abnormal and return oil

temperature is overhigh.

12) Water seeps through the turbine.

13) Quality of water and steam are not in accordance with requirements.

14) Heat preservation of the unit is imperfect.

15) Other auxiliary equipment or system fails in operation.

1.2 Preparations for start-up

1.2.1 Checking and preparations prior to unit start-up

1) All maintenance works were finished and all work sheets were reclaimed with detailed records

of maintenance;

2) The site is clean and the pass is unobstructed and lighting is good;

3) The unit is good through interlock protection test and test prior to start-up;

4) There is no jamming in the rotating parts of all auxiliary equipment. Bearing lubricating oil,

cooling water and sealing water system are normal;

5) All water and oil level meters are in operation;

6) Cooling tower and vacuum pump separator have been made up to normal water level;

7) The oil level of turbine main oil tank and EH oil tank is normal, oil circulation is good and oil

quality is qualified. The oil level of all power equipment is normal;

8) The industrial water system has been put into operation and is normal;

9) The rotating machine is normal through trial run part by part;

10) The compressed air system for instrument has been put into operation and is normal;

11) The feed water system is to be checked for normal and the auxiliary oil pumps of feed water

pump A and B are to be started;

12) Position of valve is to be checked for correct;

13) The condenser and deaerator have been filled with water and water quality is qualified

through test;

- 26 -


14) Instrument and tools used in operation are to be prepared and checked;

1.2.2 Tests prior to turbine start-up (after overhaul and minor repair of unit)

1) Static test of turbine governing system;

2) ETS test of turbine;

3) Major interlock test of the unit;

4) Interlock test of starting oil pump, AC lubricating oil pump and DC lubricating oil pump of

turbine, and interlock test of jacking oil pump and exhaust fan of main oil tank;

5) Interlock test of feed water pump;

6) Interlock test of circulating water pump;

7) Interlock test of vacuum pump;

8) Interlock test of condensate water pump;

9) Interlock test of EH oil pump;

10) Protection test of HP& LP heater and deaerator;

11) ON/OFF tests of all motor-operated valves, and pneumatical valves and hydraulic valves;

12) Interlock test of HP & LP bypass devices;

13) Interlock test of circulating water booster pump;

14) Interlock test of inner cooling water pump;

15) Interlock test of LP heater drain water pump;

16) Interlock test of shaft seal fan;

17) Interlock protection test of steam extraction check valves.

1.3 Start-up of auxiliary equipment and system of unit

1.3.1 Put the industrial water system into operation.

1.3.2 Put the circulating water system into operation.

1.3.3 Put the compressed air system into operation.

1.3.4 Put the auxiliary steam system into operation that is operating normally.

1.3.5 Put the condensate water system into operation.

1.3.6 Put the feed water deaerating system into operation, fill the deaerator with water and put

heater into operation.

1.3.7 Start the AC lubricating oil pump of turbine to make oil circulate until the oil quality is

qualified through test, start the starting oil pump and shut down the AC lubricating oil pump. Put

the AC and DC lubricating oil pump to “Automatic” position and increase the oil temperature to

above 35℃.

1.3.8 Put the EH oil system into operation to make oil circulate until oil quality is qualified through

test. Maintain the oil temperature inside the system within the range of 43~54℃.

- 27 -


1.3.9 Put the jacking oil system into operation and put continuous turning of unit into operation

after the jacking oil pressure of all bearings is normal through checking. The unit shall be put into

continuous turning operation for at least more than 4 hours prior to the turbine start-up.

1.3.10 Check the Air cooler system is ok.

1.3.11 Put the generator’s air cooling system into operation.

1.3.12 Start the vacuum pump to build up vacuum of condenser to 30kPa.

1.3.13 After warming up of shaft seal pipe by water drain is normal, start the shaft seal fan to put

the shaft seal system of turbine into operation. The LP cylinder shaft seal steam temperature

shall be within the range of 121~177 . Inform the boiler staff to ignite the boiler when the℃

vacuum of condenser reaches 70kPa.

1.3.14 Ignite the boiler to increase temperature and pressure.

1.3.15 Put the bypass system (first the LP bypass and then HP bypass) into operation after

warming up the piping. Put the bypass automatic control into operation.

1.3.16 Start the feed water pump according to the water level of steam drum. The water goes via

bypass valve of the HP heaters. Adjust the water flow with feed water bypass (or conduct water

filling with condensate water-filling pipe). Close the recirculation valve of economizer in water

filling.

1.3.17 Timely open the water filling valve of HP heater after feed water pump start to ensure the

HP heater has the condition of put-in of water side.

1.3.18 The up rate of temperature and pressure shall be as per the requirement of boiler cold

start.

1.3.19 When the initial steam pressure reaches 0.1Mpa, check and confirm the drain valve before

the main stop valve is in open position, check the tightness of HP & MP main stop valves and HP

exhaust check valves to prevent cold water and steam from going into the turbine;

1.3.20 When the pressure rises to 0.5~1.0Mpa, advise the chemical staff to test the steam quality

to decide whether to put continuous blowdown flash tank into operation according to chemical

treatment requirement.

1.3.21 The turbine can be impulsed when the steam pressure rises to 1.5~1.6Mpa, initial steam

temperature to 360℃, reheat steam temperature to 300℃, the temperature difference between

initial steam side and reheat steam side is not more than 17℃, the steam quality is qualified

through test grade and all parts of boiler are normal.

1.4 Impulsing of turbine

1.4.1 Check if the turbine protection ETS system is put into operation normally.

1.4.2 Check if the display of DEH panel is normal.

1.4.3 Condition and preparation for unit impulsing

- 28 -


1.4.3.1 Steam conditions of turbine cold impulsing:

Initial steam pressure: 1.5~1.6Mpa;

Initial steam temperature: 360℃;

Reheat steam temperature: 300℃ (the temperature of the initial steam and reheat steam

shall have the superheat degree of 50 at corresponding pressure)℃ ;

Temperature difference between initial steam side and reheat steam side <17℃;

Vacuum: above 70 kPa;

Oil temperature: about 35 ~ 42℃.

1.4.3.2 Check the initial steam pressure and temperature on DCS and DEH that shall meet the

requirement of turbine impulsing;

1.4.3.3 The turbine is in turning state, turning gear current is normal and continuous turning time

is not less than 4 hours;

1.4.3.4 Water side of both HP and LP heater are into operation, HP and LP heater start along with

the turbine prior to turbine impulsing.

1.4.3.5 Make sure all drain valves from turbine proper to the drain water flash tank are opened,

water flows through HP and LP heater normally; heater drain water system adopts automatic flow

stage by stage, and all heater motor-operated emergency drain valves are on “Auto” condition;

1.4.3.6 Maintain the vacuum of condenser above 80kPa;

1.4.3.7 Check if the water spraying system of LP cylinder is on “Auto” position and the pressure of

condensate is normal;

1.4.3.8 Check if the recirculation valve of feed water pump is on “Auto” position.

1.4.3.9 Control of the drain valves of turbine proper and initial & reheat steam piping is on “Auto”;

1.4.3.10 Check if the turbine lubricating oil temperature is within 38~42℃;

1.4.3.11 Turbine lubricating oil pressure is 0.08~0.147Mpa, and oil pressure of EH oil system is

normal;

1.4.3.12 Check if the eccentricity of shaft is >P 0.076mm and exceed the original value by 0.03mm;

1.4.3.13 Check if the differential expansion of turbine is normal;

1.4.3.14 Check if the temperature difference between of upper and lower cylinder of turbine is

normal.

1.4.3.15 Check the “Emergency governor handle” on turbine head that shall have been pulled to

“Reset” position.

1.4.4 Operation of “Operator Auto Mode” impulsing

1.4.4.1 Put the “Operator Auto” on “IN” in “Control Mode”. Click the button MODE on the upper

left side of the “DEN OVERVIEW” picture, then the sub-picture “CONTROL MODE” will appear.

Click the button “OA” and click button “IN” within 3 seconds to put in the Operator Auto Mode.

- 29 -


1.4.4.2 Reset the low pressure safety oil emergency governor on the head of turbine and check if

the low pressure safety oil is normal;

1.4.4.3 Click “LATCH” button of hand-controlled panel on control panel “DEH MAN PANNEL” to

reset the unit. After turbine reset, check the indicator of governor “TRIPPED” that shall change

into “LATCHED” reset indicator.

1.4.4.4 Open the “Limit Value” picture to input valve limit value 120% and click button “GO”,

check if the valve limit value is set normally and locally check if safety oil pressure is normal. Click

the main stop valve opening button “TVOPN” on the control panel “DEH MAN PANNEL”, and

locally check if HP & MP main stop valves are wide open and check if the HP & MP governing

valves are closed after the picture displays that HP & MP main stop valve are wide open.

1.4.4.5 Set the target speed at 500rpm and speed up rate at 50rpm/min on the set value sub-

picture “CTRL SP”, press button “GO”, here the turbine starts to impulse and speed up, check the

turbine speed that shall rise step by step.

1.4.4.6 Check the turning gear that shall trip automatically to stop turning motor when the speed

is > 60r/min.

1.4.4.7 Check and open the high pressure exhaust check valves, extraction check valve 1, 2, 4

and 5, open steam extraction motor-operated valve 1, 2, 4, 5 (1 and 2 may not be opened when

HP heater does not start along with the turbine) and put interlock into operation.

1.4.4.8 Press the button “HOLD” hold the speed when turbine speeds up to 500r/min, check the

operating condition of turbine in an all round way and warm the turbine for 4 min at a low speed:

a. Listen to check if the sound of rotating parts of the turbine-generator unit is normal;

b. Check if all bearings’ temperature and return oil temperature, vibration and oil flow are normal,

and pay attention to checking and governing lubricating oil temperature within the range of

38~42℃;

c. Check if the water spray valve of LP cylinder has been opened really, the control switch is on

“Auto” and LP cylinder exhaust temperature is < 80℃;

d. DEH & check locally to confirm:

Rotor eccentricity <0.076mm;

Rotor Vibration <76μm;

Axial displacement within ±1.0mm;

Indication of absolute expansion of cylinder is normal;

Temperature difference between the upper and lower HP cylinder < 50℃

Superheat degree of initial steam is ≥ 50℃.

1.4.4.9 Continue to set the target speed at 2,500 r/min and speed up rate at 40rpm/min. Jacking

oil pump A and B shall stop automatically when the speed reaches 1,500r/min, otherwise stop

- 30 -


them manually;

1.4.4.10 Time of turbine speed up and warming is distributed as follows:

Rotating speed

r/min

Time (min) Temperature of HP

stator lower carrier

( )℃

Overall expansion

of cylinder

mm

Vacuum of

condenser

Mpa (a)Speed up Stay

Hold 300~500 10 4 60 1 0.0347

From 500 to 2,500 50 4 130 3.5 0.0213

From 2,500 to 2,96010

2 Above 150 5~6Full

vacuum

Up to 3,000 to

incorporate into

network

10

/ Above 150 5~6Full

vacuum

It requires about 90 min from impulsing to full speed.

1.4.4.11 Make speed up to 2,500 r/min by the operating procedure above-mentioned and warm

up the turbine for 4 min:

a. Reinforce the checking and adjustment of all parts of the turbine during the whole speed-up

process, press the button “HOLD” on the DEH picture if any control value approaches the

upper limit and warming up is required during speed-up process, but it is prohibited to warm up

in the resonance region. The operator shall closely monitor the vibration of the unit;

b. Check if the pressure and flow of cooling water of generator’s air cooler are normal, if the

cold air temperature of steam end is essentially the same with that of slip ring end of generator

in idle running.

1.4.4.12 Continue to make speed up until 2,960r/min at a speed up rate of 50rpm/min by the

operating procedure above mentioned and perform checking. Pay attention to checking the

operating condition of main oil pump and confirming it is operating normally when the speed is up

to 2,800 r/min.

1.4.4.13 If everything is normal thorough check, continue to make speed up until 3000rpm, after

all parts of turbine are normal through an overall check, locally check the high pressure exhaust

check valves that shall be opened;

1.4.4.14 Perform oil injection test, valve leak test and electric overspeed test to the turbine as

required, it is required to ensure the unit is qualified through oil injection test and local & remote

trip test and operates on load for more than 4 hours.

1.4.4.15 Perform local and remote trip test to the turbine.

1.4.4.16 Check the main oil pump locally if its outlet oil pressure of is 1.18Mpa, inlet oil pressure

is 0.098~0.3Mpa and operation is normal.

1.4.4.17 Check if AC and DC lubricating oil pump interlock are on Auto position, after main oil

- 31 -


pump operates normally through check, stop the starting oil pump and confirm the starting oil

pump interlock is on Auto position.

1.4.4.18 Check if lubricating oil pressure, EH oil pressure and temperature are normal.

1.5 Unit incorporation into power network & initial load on

1.5.1 Generator synchronous paralleling

Hold the speed of unit at 3000rpm and perform an overall check, if everything is normal, advise

the electric personnel to parallel in the generator. After the electric test ends and the automatic

synchronization conditions are fulfilled (with speed at 2950~3050rpm) and upon receiving the

signal “ASPERM” from electric personnel, press the button “MODE” on the upper left of DEH

control picture, then MODE sub-picture will appear, press the button and click button “IN” within 3

seconds to put “AUTOSYNCHRONIZATION” control mode into operation, the main picture will

display enter the mode “AS” at the same time.

1.5.2 Checking after generator paralleling in and precautions in load on

1) After paralleling in, the generator is to have 5% active load and to a certain amount of inactive

load on to maintain the generator voltage and warm up the unit.

2) After paralleling in, gradually close the high and low pressure bypass according to the pressure

and temperature of steam.

1.5.3 Unit is to have initial load on for 5-10 min for warming up.

1) After paralleling in, the unit is to have initial load on 6~7MW load (5% of rated load), hold the

steam conditions for 5 min to observe if the unit system is normal as having little load on.

2) Put the primary FM control circuit into operation as the case may require.

3) Checking & operation during warming up with initial load:

A. The unit can operate with initial load for 5-10 min stably as the case may require;

B. Warm the steam extraction # 3 to make preparation for steam supply of auxiliary header;

C. Check if the temperature of generator stator core and coil are normal;

D. Check if the turbine vibration, differential expansion, cylinder expansion, axial displacement,

each bearing metal temperature, return oil temperature, lubricating oil pressure and differential

temperature between upper and lower wall of cylinder are normal.

E. Put the water level control into “Auto” after the water level of deaerator becomes stable.

F. Check if the HP and LP heater operation are normal.

1.6 Load up

1.6.1 After warming up with initial load ends, check if the turbine cylinder expansion is normal

without jamming;

1.6.2 Put the governing stage pressure circuit into operation as the case may require in the

- 32 -


process of load up;

1.6.3 Make the load up to 13.5MW (10% of rated load) by means of valve position at a load up

rate of 0.6MW/min.

1.6.4 Check if the auto operation of bypass system is normal, bypass valves close gradually with

rise of unit parameters.

1.6.5 When the load is up to 13.5MW (10% of rated load), steam pressure to 2.0~3.5 Mpa, initial

steam temperature to 450℃, reheat steam temperature to 400 and the temperature of HP℃

stator lower carrier to 390℃, check if the drain valve at upstream of MP combined valve closed

automatically, if not, close it manually.

1.6.6 When the load reaches 27MW (20% of rated load), check if the water spray device closed

automatically according to LP cylinder exhaust temperature, if not, close it manually. It may put

the unit power control circuit into operation at this time.

1.6.7 When the load reaches 27MW (20% rated load):

A. Check if the initial steam pressure is 4~5 Mpa, temperature is 470 and reheat steam℃

temperature is 430℃;

B. Check if the drain valve at downstream of MP combined valve closed automatically, if not,

close it manually;

1.6.8 When the feed water pump flow is >280t/h, confirm the recirculation motor-operated valve

of feed water pump closed by interlocking;

1.6.9 Open the sub-picture controlling set value on DEH control picture to set the target load at

60MW and load up rate at 1.3MW/min, press the button GO to make load of unit continue to go

up.

1.6.10 When the pressure of extraction #3 is > 0.25Mpa, open the extraction #3 to the motor-

operated valve of deaerator; and close gradually the auxiliary steam header to deaerator, here

the deaerator operates in sliding pressure mode;

1.6.11 When the steam side pressure of No.2 HP heater is 0.3 MPa higher than that of deaerator,

change the water drain of HP heater into the deaerator; close the water drain of HP heater valve

to condenser valve, slightly open the HP heater No.1 and No.2 to the air valve of deaerator.

When the pressure of steam extraction #3 is > 0.3 Mpa, change the steam supply of the auxiliary

header into the steam extraction #3 of this unit.

1.6.12 As the load reaches 54MW (40% rated load), initial steam pressure to 7Mpa and

temperature to 470℃ and reheat steam temperature to 450 , start on℃ e LP drain water pump

according to the water level of LP heater, close water drain of LP heater to drain valve of

condenser, and put the auto control of drain into operation when the water level is adjusted to be

normal.

- 33 -


1.6.13 When the load reaches 121.5MW (90% of rated load), steam conditions shall be up to

nominal parameters in which initial steam pressure is 13.24Mpa, initial and reheat steam

temperature are 535℃:

1.6.13.1 From warming up with initial load to 90% of rated load, the time of steam conditions

reaching the ratings shall be controlled at 120 min;

1.6.13.2 Put the “Initial Steam Pressure Control” into operation on the DEH panel as the case

may require after initial steam pressure reaches the rating;

1.6.14 Change the control mode of valves from “Single Valve Control” to “Sequence Valve

Control” after the unit load reaches over 50MW, and pay attention to the change in load in

changeover.

1.6.15 Continue to make load up until 135MW, perform an overall check and report the check

results to the unit supervisor.

1.7 Precautions in unit start-up

1.7.1 Pay attention to the operating condition of all automatic governing devices, change into

manual governing control if any fault or poor governing, and contact the thermodynamic

personnel to treat.

1.7.2 Pay attention to listening if the unit sound is normal.

1.7.3 Pay attention to checking if water level of condenser, deaerator and HP&LP heater are

within normal range.

1.7.4 In load up, monitor if the generator air temperature is normal and adjust the rotor water inlet

pressure to normal in time.

1.7.5 As vibration over critical speed exceeds 0.254mm, but protection refuses to operation, trip

to shut down the turbine manually, put continuous turning into operation, measure shaft

deflection, find out cause and remove fault, restart the unit, the duration of continuous turning

operation shall be > 4hours.

1.7.6 If the initial steam temperature rises or lowers by over 50 within℃ 10 min in start-up, it is

required to trip to shut down the turbine immediately.

1.7.7 During turbine speed up, if it is required to hold the speed of turbine, press the button

“HOLD” on DEH control panel. If the turbine is within the range of resonance speed, reduce the

speed quickly to below the range of resonance speed and then hold it.

1.7.8 Rotor eccentricity: as the turbine speed is lower than 600r/min, monitor the rotor eccentricity

which value shall be <0.076mm, turbine impulsing is not permitted as the rotor eccentricity

reaches this value.

1.7.9 Vibration: when the speed reaches over 600r/min, monitor the bearing vibration. It can be

- 34 -


regarded as qualified if bearing vibration ≯0.076mm. When the speed is lower than 1300r/min, it

shall be regarded as qualified if pad vibration ≯0.03mm, it is necessary to trip to shut down the

turbine in excess of 0.03mm. It is necessary to trip to shut down the turbine as the pad vibration

exceeds 0.1mm over critical speed (or vibration increases suddenly with abnormal noise if not up

to 0.05mm).

1.7.10 Differential expansion:

Positive differential expansion of HP & MP cylinder must not exceed +8mm, and it is necessary to

shut down the unit immediately if so; negative differential expansion of HP & MP cylinder must

not be less than -3mm and it is necessary to shut down the turbine immediately if up to -3mm; in

the process of speed up, closely monitor the differential expansion, hold the speed if discovering

differential expansion alarm, and shut down the turbine as up to the shutdown value.

1.7.11 Absolute expansion of cylinder:

In start-up, pay attention to monitoring the absolute expansion of cylinder and compare with the

same in the first start-up to prevent cylinder expansion from being obstructed, cylinder shall

expands continuously with jamming, if expansion is abnormal, it is required to reinforce warming

up, find out and remove the cause.

1.7.12 Differential temperature between upper and lower part of the cylinder: must not be more

than 50℃.

1.7.13 Axial displacement: must not exceed ±1mm. Shut down the turbine as up to ±1.2mm.

1.7.14 LP cylinder exhaust temperature: must not exceed 80℃ (alarm value), shut down the

turbine as up to 121℃.

1.7.15 Metal temperature and return oil temperature of all bearings:

(1) Normally return oil temperature of all bearings shall be below 75℃; shut down the turbine as

up to 80℃;

(2) Outlet oil temperature of oil cooler is within 38℃~42℃;

(3) Metal temperature of journal bearing ＃1~3 shall be below 107℃; shut down the turbine as up

to 113℃; the metal temperature of journal bearing＃4~5 shall be below 75℃, shut down the

turbine as up to 80℃;

(4) Metal temperature of thrust bearing shall not be higher than 99 ;℃ shut down the turbine

immediately as up to 107℃;

(5) Lubricating oil pressure is within 0.09~0.15Mpa.

1.7.16 Before the unit impulsing, adjust the initial and reheat steam parameters to meet the start-

up requirements by bypass, generally these is no need to adjust the parameters in the process of

unit speed up so as not to affect the rotating speed. After the unit paralleling in, check if the

automatic control of bypass is normal and pay attention to that the tracking of attemperating

water shall be normal; the adjustment of the opening extent of HP & LP bypass shall be based on

- 35 -


the need of boiler to prevent too acute oscillation of MP governing valve as a result of too high

steam pressure of boil side and too large opening of bypass, at the same time pay attention to

the pressure difference before and after HP exhaust steam check valve to prevent it from being

closed and causing chocking.

1.7.17 Strictly monitor the water level of HP & LP heater, deaerator and condenser in the process

of start-up.

1.7.18 Temperature rise & decrease rate

Name Temperature rise rateTemperature decrease rate

Temperature of initial steam <2~2.5 /min℃ <1.5 /min℃

Temperature of reheat steam <3~3.5 /min℃ <2.5 /min℃

Outer wall of initial and reheat steam pipe 8℃/min

Outer wall of steam valve 4~6℃/min

Flange wall of cylinder 2~2.5℃/min

1.7.19 Temperature difference

Name UnitIn temperature

rise

In temperature

decrease

Temperature difference between upper

and lower part wall of HP & MP outer

cylinder stator carrier

℃ <30


and lower par of HP & MP outer

cylinder and flange

℃ <50 <40


and lower part of HP & MP outer

cylinder

℃ <50

Temperature difference between initial

steam and reheat steam℃ 40~70 <40

Temperature difference between left

and right main reheat steam pipe℃ <17

- 36 -


Chapter 2 Warm & Hot Start of the Unit

2.1 Preparations prior to boiler ignition

2.1.1 Prior to boiler ignition, the check and preparation of turbine system are the same with

section 1.1 and 1.2 of Cold Start;

2.1.2 The systems to be put into operation prior to turbine start-up are the same with section 1.3

of Cold Start;

2.1.3 The following rules shall be observed in warm & hot start of unit besides the requirements

for Cold Start.

1) Supply steam to shaft seal while the turning gear is in operation, and then start the vacuum

pumps to vacuumize the condenser. Drain water sufficiently in the process of supplying steam to

shaft seal to raise the temperature of shaft seal to make the shaft seal steam temperature

approach the shaft seal housing temperature and its temperature difference with HP shaft seal

housing not exceed 30℃ to prevent bearing journal from cooling as supplying shaft seal steam

and resulting in bending of shaft.

2) The outlet oil temperature of oil cooler shall be maintained comparatively higher and generally

not lower than 40℃.

3) In order to prevent untight HP auto main stop valve, speed governing valve and MP combined

valve from resulting in automatic impulsing of turbine or high temperature parts being cooled

down, so it is inappropriate to maintain the vacuum of condenser and initial steam pressure too

high.

- 37 -


4) In the case where there is excess pressure in boiler, the extraction system must be put into

operation to set up the vacuum of condenser prior to boiler ignition so as to prevent the exhaust

rupture disk of LP cylinder from operating.

2.2 Boiler ignition

2.2.1 The start-up procedure of boiler follows that of Cold start and temperature & pressure rise

follows the Hot Start Curve of turbine.

2.2.2 For hot start, pay attention to maintaining the parameters stable as up to impulsing

parameters.

2.3 Impulsing speed up of turbine

2.3.1 Preparations prior to turbine impulsing

2.3.1.1 Keep continuous turning time more than 4 hours prior to impulsing with the shaft

eccentricity of less than 0.076mm.

2.3.1.2 Feed water pump shall be in good standby condition.

2.3.1.3 Drain water to warm up pipe sufficiently prior to supplying steam to shaft seal, it is strictly

prohibited to let cold steam and water in the shaft seal system of turbine, and adjust the

temperature of shaft seal to normal.

2.3.1.4 Check of DEH panel (procedures as Cold Start)

2.3.2 Fix impulsing parameters as per the following table according to cylinder temperature:

Item Warm state Hot state Remarks

upperr half metal

temperature of HP

inner cylinder ( )℃

150~300 300~400

Initial steam

temperature ( )℃

At least 50 higher than℃

the lower half metal

temperature of HP stator

carrier

At least 50℃ higher

than the lower half

metal temperature of

HP stator carrier

With 50℃ superheat

degree under

corresponding

pressure

Reheat steam

temperature ( )℃

At least 30℃ higher than

the lower flange metal

temperature of MP cylinder

At least 30℃ higher

than the lower flange

metal temperature of

MP cylinder

With 50℃ superheat

degree under

corresponding

pressure

Time from

impulsing to full

speed (min)

50 10

Max speed in

speed up (r/min)100

450

Must not be more

than 500

- 38 -


2.3.3 Impulsing speed up of turbine:

2.3.3.1 Checking and tripping operation of DEH panel are the same with that of Cold Start;

2.3.3.2 Fix the impulsing time and speed up rate according to cylinder temperature;

2.3.3.3 Other operations and checking in the process of turbine speed up are the same with that

of Cold Start.

2.3.3.4 Because HP automatic main stop valve, speed governing valve, MP combined valve and

steam lead pipe, etc. parts can cool quickly after shutdown, pay attention to the temperature rise

rate of them in start-up to prevent excessive heating and pay attention to the vibration of unit.

2.4 Unit paralleling in & load on

2.4.1 “Operator Auto” mode:

2.4.1.1 Make load up to the rated value according to the load variation rate looked up in the Hot

Start Curve;

2.4.1.2 Other operations in the process of unit load up are the same with that of Cold Start.

2.4.2 Major operations in the process of load up shall be done after steam temperature, steam

pressure, load and water level of steam drum and deaerator become stable, and the parameters

in operation shall meet the specification.

2.5 Precautions in hot start

2.5.1 Slowly open the high and low pressure bypass to warm up pipe after boiler ignition in the

condition where the vacuum of condenser is definite, close the drain valve of LP reheat steam

inlet after warming up;

2.5.2 First put shaft seal into operation and vacummize the turbine then. After vacummization,

closely monitor the change in cylinder temperature and operation of turning gear to prevent over

high temperature difference between the upper and lower cylinder.

2.5.3 The lubricating oil temperature shall not be lower than 35℃ in impulsing and pay attention

to adjusting the oil temperature after implusing.

2.5.4 Check thoroughly and rapidly in the process of speed up of turbine, it is strictly prohibited to

over the critical speed blindly.

2.5.5 Closely monitor the unit’s vibration, differential expansion and cylinder expansion in the

process of start-up;

2.5.6 Make the unit have initial load according to cylinder temperature as soon as possible after

paralleling in;

2.5.7 Reinforce water drain of the initial steam pipe and turbine proper in hot start to prevent cold

- 39 -


water or steam from flowing into the cylinder in impulsing.

2.5.8 In hot start, prevent overhigh HP cylinder exhaust temperature to parallel in quickly as up to

the rated speed. If necessary, open wider the low pressure bypass to lower the reheat steam

pressure and control the HP cylinder exhaust temperature to be lower than 360℃.

PART 3 Unit Operation

- 40 -


Chapter 1 Operating Parameters of Steam Turbine

1.1 Monitoring of steam conditions in normal operation of turbine

Name UnitNormal

valueMax Min. Remarks

Initial steam pressure (a) MPa 13.24 13.73shut down the unit immediately

as up to 14.22 Mpa

Initial steam temperature ℃ 535 540 520

Duration at 553℃ must not

exceed 15min and trip the unit

immediately as exceeds 565℃

Reheat steam pressure MPa 2.238 2.445

Reheat steam temperature ℃ 535 540 520 As the initial steam temperature

Initial steam flow t/h 398.9 440

Reheat steam flow t/h 335.2 360.9

Temperature difference

between initial and reheat

steam

℃ <40

Temperature difference

between two sides of initial

steam and reheat steam

℃ <17

- 41 -


HP cylinder exhaust

pressure MPa 2.531 3.0

HP cylinder exhaust

temperature℃ 312.1 321.6

LP cylinder exhaust

pressure kPa 8.83 20.3

LP cylinder exhaust

temperature ℃ <65 120

Alarm at 80℃， shut down at

121℃

1.2 Pressure of each monitored section: (MCR) Unit: Mpa (a)

Governing

stage

Extraction

steam

No.1

Extraction

steam

No.2

Extraction

steam

No.3

Extraction

steam

No.4

Extraction

steam

No.5

Extraction

steam

No.6

Extraction

steam

No.7

10.34 3.5516 2.4566 0.7301 0.4509 0.2515 0.067 0.0143

1.3 Shaft seal system

Name Unit Normal value Max Min Remarks

Pressure of steam supply header of

shaft sealMPa 0.02~0.03

LP shaft seal steam temperature ℃ 149 176 121

Vacuum of the shaft seal heater kPa -5~-7

Water level of the shaft seal heater mm1/3 of water

level gauge

1.4 Relative expansion & axial displacement of turbineName Unit Alarm value Limit value Remark

Axial displacement mm ±1 ±1.2

Differential expansion of HP & MP cylinder mm +7, -2 +8, -3

Differential expansion of LP cylinder mm +6.5 +7.5

1.5 Peak to peak vibration amplitude of rotorEccentricity alarm at 0.076mm for below 600r/min;

Bearing vibration alarm at 0.127mm for above 600r/min;

Trip for vibration at 0.254mm;

It is qualified If the bearing pad vibration is < 0.05mm and is good if less than 0.025mm at

3000r/min.

Note: motor vibration of all auxiliary equipment

It is qualified if bearing pad vibration is < 0.085mm for rotating speed at below 1,500r/min;

It is qualified if bearing pad vibration is < 0.05mm for rotating speed at below 3,000r/min.

- 42 -


1.6 Operating parameters of deaerator

Name Unit ItemOperating

valueOperating result

Water level

of deaeratormm

Normal value 2,550

High value I 2,750 Alarm

High value II 2,850Interlock open the motor-operated overflow

valve of deaerator

High value III 2,950

Interlock close the steam extraction No.3

motor-operated valve and check valve

interlocking, interlock close the motor-

operated overflow valve of the deaerator

when the water level decreases to below

2,750mm;

Low value I 2,350 Alarm

Low value II 680 Feed water pump trip

Pressure of

deaeratorMPa

Normal 0.68 Operate at sliding pressure

Low pressure 0.3 Alarm for low pressure

High pressure 0.85 Safety valve operate

1.7 Oil system of steam turbine

Name Unit Normal Max Mini Remarks

Lubricating oil

pressureMPa 0.078~0.147

Alarm at 0.08Mpa;

AC lubricating oil pump puts in at

0.07Mpa;

DC lubricating oil pump put in at

0.06Mpa;

Shut down at 0.06Mpa;

Turning stop at 0.03MPa

Inlet oil pressure of

main oil pumpMPa 0.098~0.11

Outlet oil pressure of

main oil pumpMPa 1.1~1.18

Alarm at 0.9Mpa;

Interlock start oil pump at

0.883Mpa

Outlet oil temperature

of oil cooler ℃ 38~42 45 38 Alarm at 35℃

Return oil temperature

of bearing #1-#5 ℃ <65 <75 Alarm at 65℃

Metal temperature of

journal bearing #1-3℃ <85

Alarm at 107℃, shut down at

113℃


journal bearing #4-5℃ <70 Alarm at 75℃, shut down at 80 ℃


thrust bearing℃ <85 Alarm at 99℃, shut down at 107℃

- 43 -


Name Unit Normal Max Mini Remarks

Oil level of main oil

tankmm 1808 2,616 1,245 Shut down at 1,245 mm

Inlet oil pressure of

jacking oil pump MPa Refuse to start at below 0.039MPa

oil pressure of jacking

oil headerMPa 10~12

Block start turning gear at below

4.2MPa

EH oil pressure MPa 13.7~14.5

Overflow valve operates at 16.2

Mpa;

Start standby pump at 11.03 Mpa;

Shut down at 9.31 Mpa.

Oil level of EH oil tank mm 438.15~558.8 438.15 558.8Low value II: 295.15mm

Low value III: 193.54mm

EH oil temperature ℃ 35~45 Start electric heater at below 23℃

1.8 Operating parameters of feed water pump

Name Unit Normal Max Min Remarks

Lubricating oil pressure MPa 0.2~0.3 0.3 0.17

Permit to start pump at 0.17Mpa;

Auxiliary oil pump stops

automatically at 0.22Mpa;

Alarm and auxiliary oil pump starts

automatically at 0.08Mpa;

Feed water pump trips at 0.08Mpa.

Inlet oil temperature of

lubricating oil cooler ℃ <65 70 45 Alarm at 65℃, trip pump at 70℃

Outlet oil temperature of

lubricating oil cooler℃ <55 60 35 Alarm at 55℃, trip pump at 60℃

Inlet oil temperature of

working oil cooler℃ <110 130 60 Alarm at 110℃, trip pump at 130℃

Outlet oil temperature of

working oil cooler ℃ <75 85 35 alarm at 75℃, trip pump at 85℃

differential pressure of

coupling lubricating oil

strainer

MPa 0.01-0.03 0.06alarm at 0.06MPa, it need to switch

the strainer

Journal bearing

temperature of feed water

pump motor

℃ Alarm at 80℃, stop pump at 90℃

- 44 -


Name Unit Normal Max Min Remarks

Journal bearing

temperature of booster

pump

℃ 70 90 Alarm at 75 ,℃ stop pump at 90℃

Journal bearing

temperature of feed water

pump

℃ 70 90 Alarm at 75 ,℃ stop pump at 90℃

Thrust bearing temperature

of feed water pump℃ 75 95 Alarm at 80 ,℃ stop pump at 95℃

High inlet flow of feed water

pump t/h Recirculation is ON at > 280 t/h

Low inlet flow of feed

water pump t/h Recirculation is OFF at < 132 t/h

Temperature of rotor

winding of feed water pump

motor

℃ 130 Alarm at 120 ,℃ stop pump at 130℃

Temperature of all bearings

inside the coupling℃ <90 95 Alarm at 90 , ℃ trip pump at 95℃

Differential pressure of

sealing water

MP

a>0.1

1.9 Operating parameters of HP heater

Name UnitNormal

valueRemarks

Water

level of

HP heater

No.1

mm 700

Alarm at High Value I (850mm);

Interlock open the emergency drain valve of corresponding HP

heater at High Value II (1000mm). Close the emergency drain valve

of corresponding HP heater when the water level lowers to 600mm;

Parallel HP heaters off and close motor-operated steam inlet valve

of HP heater at High Value III (1200mm).

Water

level of

HP heater

No.2

mm 975

Alarm at High Value I (1125mm);

Interlock open the emergency drain valve of corresponding HP

heater at High Value II (1275mm). Close the emergency drain valve

of corresponding HP heater when the water level lowers to 875mm;

Parallel HP heaters off and close motor-operated steam inlet valve

of HP heater at High Value III (1475mm).

1.10 Quality requirement for various types of water

Name Hardness Dissolved oxygen Conductivity SiO2 (μg/l) PH value

- 45 -


(μmol/l) (μg/l) (μs/cm)

Condensate Approach 0 ≤40 ≤0.3 ≤20

Feed water Approach 0 ≤7 ≤0.3 ≤20 8.8~9.3

Boiler water ≤50 ≤450 9.0~10

1.11 Steam quality

Item Iron ppb Copper ppb Sio2 μg/l Sodium μg/lConductivity

ms/cm

Permitted value ≤20 ≤5 ≤20 ≤10 ≤0.3

Chapter 2 Operating Modes of the Unit

2.1 BASE

In this mode, both the power and pressure control circuit have been cut off, the main controller of

turbine-boiler is controlled by operators manually. On the boiler side, change the boiler load

demand manually to adjust the initial steam pressure. ON the turbine side, change the turbine

load demand to control the unit’s power through DEH.

Unit shall be switched to Base mode if any condition as follows is met:

MFT operating;

Operator selected the Base mode;

Both boiler main controller and turbine main controller are operated manually at the same time.

2.2 Cooperative control system

In this mode, the main controller of turbine is on Auto position to adjust the power automatically

according to the UD. The main controller of boiler is also on the Auto position, the heat signal is

compared with the energy balance demand and calculated to be taken as the demand of main

controller of boiler.

- 46 -


When the load changes, the turbine makes control demand first to take advantage of the boiler’s

thermal storage capacity to adapt to the need of load. Here the initial pressure decreases

gradually; when the deviation between initial steam pressure and specified value is higher than

the dead-band of module, the output and unit power demand are summed up and sent to the

turbine side to limit the initial steam pressure to change further. At the same time, the combustion

rate on boiler side changes quickly to make the initial steam pressure return to the range of

specified value. This control mode is commonly used by general unit plant that takes advantage

of thermal storage capacity of boiler and ensures the stability of steam pressure.

Cooperative control system requires both boiler main controller and turbine main controller are on

Auto position, otherwise it is unavailable.

2.3 Boiler following

In this mode, the main controller of boiler is on Auto position, the initial steam pressure governing

circuit is in operation, the main controller of turbine is on Manual position, the unit’s power control

circuit is cut off, the unit load is controlled by operator manually and the control demand is sent to

DEH directly. When the load changes, the turbine sends out control demand first until the initial

steam pressure changes, then the boiler side sends out control demand.

BF mode takes full advantage of the thermal storage capacity of boiler to make the unit’s power

respond quickly. Consequently this mode possesses better initial load response characteristic,

which is in favor of carrying variable load and frequency modulation of power network. However

because the boiler’s thermal inertia is very high, it is easy for excessively violent change in actual

load demand to cause overuse of boiler’s thermal storage and result in much fluctuation of initial

steam pressure, which is unfavorable to safety and stability of unit operation.

2.4 Turbine following

In this mode, the turbine main controller is on Auto position and the power control circuit of unit is

cut off and the pressure control circuit is switched to the turbine side. The governing valve of

initial steam pressure is controlled by DEH to maintain within the range of specified value

automatically. On boiler side, if the main controller is on Manual position, the operator shall

change the load demand of boiler load according to load demand of unit. After initial steam

pressure changes, the turbine side changes the opening of governing valve automatically thus to

change the unit load. If the main controller of boiler is on Auto position, the main controller of

boiler receives the actual load demand through switcher with the initial steam pressure still

governed by the opening of governing valve.

The TF mode takes no advantage of the thermal storage of boiler, so the output power is only

able to respond to the change in actual load demand by means of change in combustion of boiler

- 47 -


making evaporating capacity, thermal storage capacity and steam pressure change, which has a

much longer delay and poor adaptability of unit to change in load, so it is unfavorable to carrying

variable load and participating in frequency modulation of power network and is generally used in

the case where main auxiliary equipment of boiler fail.

2.5 Operating mode of unit protection & interlock

All protections and interlocks must be put into operation as long as the equipment starts. They

can only be stopped by order given by the shift engineer after strict procedures of examination

and approval. After the auxiliary equipment become normal after start-up, the standby

equipment’s interlocking switch shall be put into operation in time to ensure good standby

function.

After power equipment trips, it must first check if the electrical protection operated and then

confirm thermodynamic protection. The tripped equipment must not be put into operation until trip

cause is found out, clear written report by maintenance personnel and approval by shift engineer

are required if it is must be put into operation again. After the equipment is interlocked in

operation, the original running equipment shall be checked thoroughly, if the cause is unavailable,

the original running equipment shall be shut down for a detailed check.

- 48 -


Chapter 3 Regular Works and Requirements

3.1 In order to ensure normal operation of the unit, the operator on duty shall check and maintain

all systems and equipment regularly.

3.2 When the unit is operating normally, record the operation log table every hour. The records

shall be punctual, accurate and written legibly, compare and analyze the running state from time

to time, and find out the cause and give treatment in time if discovering any abnormity.

3.3 The operator on duty is required to check the subordinate equipment regularly.

3.4 Test and regular switching of equipment shall obtain approval from the unit supervisor and be

performed by the supervisor and operator duly who shall fulfill each work required by the test

under unified leadership of the shift engineer.

3.5 Record the regular work; record detailedly the cause for the equipment that can not be tested

and switched, and report to the shift engineer and shift leader; Contact for treatment if any

problem in test, stop the test if necessary and continue test until the problem is solved.

3.6 The switched equipment must be restored to standby.

3.7 Release the interlocking of the equipment with automatic interlock in regular works that shall

put into operation as standby state restores.

3.8 If any abnormal in regular works, stop the operation immediately and perform according to the

demand.

3.9 It is prohibited to put the equipment with unqualifiedly-insulated motor into operation or

standby, but advise the maintenance personnel to treat immediately.

3.10 For the unit is in outage or does not satisfy the test conditions, all specified test items shall

be done in next start-up or regular test period.

3.11 The equipment, which has already been tested for the interlock protection (which had been

started after routine maintenance or overhaul) within the time limit of specified test & switching,

can be exempted this time of regular test.

- 49 -


Att. List of Equipment Regular Works

No. Work contents Time requirement Operator Supervisor

1Test of emergency sound &

thermodynamic signalPer shift

Vice operator

on duty

Operator

on duty

2 Check of the oil level gauge of oil tankDaytime shift per

day

Vice operator

on duty

3Moving test of HP & MP main stop

valve

Daytime shift on

Monday

Operator on

duty

Unit

supervisor

4 Moving test of extraction check valvesDaytime shift on

Monday

Operator on

duty

Unit

supervisor

5Water drain of main oil tank and feed

water pump oil tank

Daytime shift on

Thursday

Routine

inspector

6 Vacuum leak test Daytime shift on the

5th per month

Operator on

duty

Unit

supervisor

7 Switching of vacuum pumpDaytime shift on the

10th per month

Vice operator

on duty

Operator

on duty

8Switching of LP heater drain water

pump

Daytime shift on the

10th of per month

Vice operator

on duty

Operator

on duty

9 Switching of industrial water pumpDaytime shift on the

10th per month

Routine

inspector

Operator

on duty

10 Switching of shaft seal fanDaytime shift on the

10th per month

Vice operator

on duty

Operator

on duty

11Starting test of feed water pump

auxiliary oil pump


15th per month

Vice operator

on duty

Operator

on duty

12 Switching of main oil tank exhaust fan Daytime shift on the

15th per month

Vice operator

on duty

Operator

on duty

13 Switching of feed water pumpDaytime shift on the

15th per month

Operator on

duty

Unit

supervisor

14

Starting test of starting oil pump, AC &

DC lubricating oil pump, jacking oil

pump and turning gear motor


20th per month

Operator on

duty

Unit

supervisor

15Switching of EH oil pump and inner

cooling water pump


20th per month

Operator on

duty

Unit

supervisor

16Switching of circulating water pump

and circulating water booster pump


25th per month

Operator on

duty

Unit

supervisor

17 Switching of condensate pumpDaytime shift on the

25th per month

Operator on

duty

Unit

supervisor

18 Emergency governor oil filling testOne month after

unit operating

Operator on

duty

Unit

supervisor

Note: regular switching of power equipment can be advanced if the due time meets with weekend

or holiday, but it must make records through.

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PART 4 Unit Shutdown

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1.1 Preparations prior to unit shutdown

1.1.1 After receiving shutdown command from the unit supervisor, contact all posts to make

preparations for shutdown;

1.1.2 Do starting test of AC and DC lubricating oil pump, jacking oil pump and starting oil pump of

turbine and they are normal through test, and do starting test of the steam turbine turning gear

motor and it is normal through test;

1.1.3 Switch the auxiliary steam supply to be supplied by neighboring turbine (or supplied by

starting boiler);

1.1.4 Check the unit thoroughly and count detects of equipment.

1.2 Normal shutdown

1.2.1 Confirm DEH is in “Operator Auto” mode; confirm ”lower limit of initial steam pressure” is

released.

1.2.2 Open the sub-picture of set value control on the main control picture of DEH to set the

target load at 110MW, and set the load down rate at 1.25MW//min by turning down the governing

valve in the condition of holding steam temperature and pressure, then press the button “GO” to

make the unit load start to decrease. At the same time, the main operator shall decrease the

temperature and pressure according to normal shutdown curve.

1.2.3 When the load decreases to 110MW, press button “HOLD” with the initial steam

temperature to 500℃, reheat steam temperature to 480℃, initial steam pressure to 11Mpa and

HP stator lower carrier metal temperature to 455℃.

1.2.4 Table of load, steam temperature & time at normal shutdown Load MW

Item135 110 75 54 5.4 0

Time (min) 20 51 60 71 72

Initial steam temperature ( )℃ 535 500 474 472 466 465

Reheat steam temperature ( )℃ 535 480 452 450 445 444

HP stator lower carrier metal temperature

( )℃496 455 415 410 400 398

1.2.5 Decrease the parameter and load according to the normal shutdown curve at the rate of

initial steam temperature of 1.5 /min,℃ reheat steam temperature of >P2.5 /min℃ and initial steam

pressure of 0.05Mpa/min.

1.2.6 Open the sub-picture of set value control on the main control picture of DEH to set target

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load at 75MW and load down rate at 1.13MW/min, then press “RATE” and “ENTER” button; press

“GO” button, the unit load continues to decrease.

1.2.7 When the differential pressure between HP heater #2 steam side and deaerator is <

0.3MPa, stop the HP heater steam side from high to low; close the drain motor-operated valve of

deaerator, change HP heater water drain to the condenser; close HP heater #1 and #2 to the

deaerator air valve and close the air inlet value of HP; open the drain valves before and after

extraction check valve of No. 1 and 2.

1.2.8 When No. 3 extraction pressure decreases to 0.25MPa, check if the auxiliary steam

header’s steam supply valve is opened, close the No. 3 extraction to deaerator air inlet valve;

make the deaerator run at constant pressure of 0.192Mpa.

1.2.9 Set the target load at 54MW, load down rate at 2.33MW/min and the unit load continues to

decrease; when the load decreases to 54MW, the initial steam temperature decrease to 472℃,

reheat temperature to 450℃ and HP stator lower carrier metal temperature to 410℃.

1.2.10 When the load decreases to 45~60MW, stop the LP heater drain pump and open LP

heater #6 l to multistage water-seal inlet and outlet valve; change LP heater #6 drain water to

condenser

1.2.11 Set the target load at 5.4MW, load down rate at 4.42MW/ min, and the unit load continues

to decrease.

1.2.12 When feed water flow decreases to 132m3/h, check the feed-water recirculation valve that

shall open automatically, otherwise open it manually. In the process of load decrease, check if

the shaft seal steam supply pressure is not less than 0.08 Mpa, adjust the shaft seal

attemperating water and maintain the shaft seal steam supply temperature within specified range.

1.2.13 When the load decreases to 40MW, put the auto control of HP & LP bypass according to

the requirement of boiler.

1.2.14 Open the attemperating water valve of proper drain flash tank. Close the air inlet valves of

LP heater #4~#6.

1.2.15 When the load decreases to 27MW (20％ of rated load), the drain valves of LP part shall

open automatically, otherwise open them manually.

1.2.16 When the exhaust temperature is ≥ 80 ,℃ check if the LP cylinder water spray starts to

operate automatically

1.2.17 When the load decrease to 13.5MW (10％ of rated load), the drain valves of HP part shall

open automatically, otherwise open them manually.

1.2.18 When the load decreases to 6MW, the initial steam pressure decreases to 1.57~2.06Mpa,

initial steam temperature to 466℃, reheat temperature to 445℃ and HP stator lower carrier

metal temperature to 400 ,℃ prepare to shut down the unit.

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1.2.19 Set the target load at 0 MW and load down rate at 5MW/ min, and the unit load continues

to decrease to zero.

1.2.20 Start AC lubricating oil pump, advise electrical personnel that the generator can be

paralleled off, at this time the steam turbine and boiler shall interlock trip (press the button “OFF”

to trip them in special case). Check HP & MP main stop valve, governing valve, extraction check

valve and exhaust check valves of HP cylinder A & B that shall close all; unit speed decreases.

1.2.20 Works to done during unit idle time

1.2.20.1 Check the condition of unit idling, listen to its internal sound and record the idle time;

1.2.20.2 When the rotating speed is 2,500r/min, close the air valve of condenser; when the

rotating speed is 1,500r/min, check if the jacking oil pump opened automatically, if not, open it

manually;

1.2.20.3 When the rotating speed is 300~400r/min, open the vacuum breaker valve to decrease

vacuum degree, control the rotating speed to “0” and vacuum to “0”; stop the shaft seal motor,

stop the shaft seal steam supply and close isolating valve; stop the vacuum pump.

1.2.20.4 When the unit comes to rest, put the continuous turning into operation and record the

shaft bending and turning gear current.

1.2.21 Operation after shutdown

1.2.21.1 Check HP & LP bypass that shall stop and exit.

1.2.21.2 Close the cooling water valve of oil cooler and air cooler, close the attemperating water

valve of feed water pump and open the oxygen exhaust valve of deaerator to decrease the

pressure to zero.

1.2.21.3 When boiler is filled with water, stop the feed water pump, stop the deaerator heating

and close the isolating valve.

1.2.21.4 Open the recirculation of condensate pump and adjust the water level of deaerator and

condenser.

1.2.21.5 When the exhaust hood temperature is <50 ,℃ stop the circulating water pump with

approval of unit supervisor.

1.2.21.6 When the exhaust hood temperature <50℃, stop the condensate pump with approval of

unit supervisor.

1.2.21.7 When the HP carrier lower half metal temperature is <150℃, stop continuous turning.

1.2.21.8 When the rotor comes to rest; release the interlocking of oil pump and stop the jacking

oil pump and AC lubricating oil pump.

1.2.22 Precautions in normal shutdown

1.2.22.1 In the process of shutdown, keep the initial and reheat temperature within normal range

as much as possible that shall not be lower than 450 minimally℃ .

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1.2.22.2 In the process of load down, pay attention to the change in differential expansion of HP

& MP cylinder, when the differential expansion reaches -1mm, stop load down, if such negative

value continues to increase, take measures to reduce the load quickly to zero for shutdown.

1.2.22.3 When the vibration at unit idling increases, reduce the vacuum degree to make the unit

speed lower quickly.

1.2.22.4 After the unit shuts down and before the boiler, deaerator and auxiliary steam header

release pressure completely, closely monitor the metal temperature of steam turbine to prevent

steam & water from escaping into the steam water.

1.2.22.5 If discover exhaust cylinder temperature increases after shutdown, find out the cause

and cut off steam source, or else start the condensate pump and put the LP cylinder spray into

operation to reduce the exhaust cylinder temperature. After shutdown, pay attention to monitoring

the water level of condenser and deaerator to prevent overfeed of water.

1.3 Sliding pressure shutdown

1.3.1 After receiving “Sliding pressure Shutdown” command from shift engineer, make

preparations for shutdown and get done with division of work and conduct referring to normal

shutdown.

1.3.2 Decrease the load to 100MW according to normal shutdown requirement, and then take

advantage of sliding decreasing initial steam pressure and temperature to decrease the load.

1.3.3 Change the steam source of auxiliary steam header to be supplied by neighboring turbine

or starting boiler and check if the steam pressure and temperature of auxiliary header is normal.

1.3.4 Principle of sliding pressure shutdown

1.3.4.1 Contact the boiler operator to decrease the initial steam pressure first according to sliding

parameter shutdown curve, hold the load demand and pay attention to the opening of governing

valve, governing stage temperature and lower cylinder temperature drop.

1.3.4.2 After initial steam pressure decrease, lower the LOAD DEMAND gradually according to

the load sliding down to cooperate in controlling the initial steam pressure, at this time, keep the

initial steam temperature stable as much as possible.

1.3.4.3 Contact the boiler operator to stabilize pressure and hold load, and decrease the initial

steam temperature according to the governing stage temperature and the upper-lower cylinder

temperature as per sliding pressure shutdown curve.

1.3.4.4 Every time load decreases by 10MW, keep the steam pressure, temperature and load

stable for 5 minutes.

1.3.4.5 Pay attention to the opening of governing valve, governing stage temperature and upper

cylinder temperature drop, monitor the section pressure that shall not exceed the rated value, and

keep the reheat steam temperature catch up with the initial steam temperature decreasing rate.

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1.3.5 Operation of sliding pressure shutdown

1.3.5.1 The main controller operator on duty shall reduce the pressure and temperature at the

rate of 0.04~0.049MPa/min and 1.5 /min℃ for initial steam and 2.5℃/min for reheat steam; pay

attention to controlling the load down rate at 0.4MW/min.

1.3.5.2 Reduce the initial steam temperature to 500 and pressure ℃ to 10.79MPa slowly, open

wide the speed governing valve gradually and reduce the load to 100MW and keep stable

operation for 20 minutes.

1.3.5.3 Reduce the initial steam pressure and temperature at the rate of 0.03~0.04MPa/min and

1.5℃/min, unit load continues to decrease and pay attention to controlling the load down rate at

0.4MW/min.

1.3.5.4 When the load decreases to 40MW, keep stable operation for 40 minutes.

1.3.5.5 When the initial steam flow is ≤ 30%, put HP & LP bypass and three-stage attemperating

water into operation, continue to reduce the initial steam pressure and temperature at the rate of

0.03~0.04Mpa/min and 1.5℃/min, unit load continues to decrease and pay attention to

controlling the load down rate at 0.4MW/min.

1.3.5.6 When the load decreases to 10MW, initial steam pressure to 1.6~2.0MPa and initial

steam temperature to 370 ~380 ,℃ ℃ the sliding pressure shutdown is over and prepare to shut

down. Open the sub-picture of set value control on the main control picture of DEH to set the

target load at 0MW and load down rate at 5MW/min, and the unit load continues to decrease.

1.3.5.7 Report to the shift engineer when the load decreases to zero and trip to shut down the

unit.

1.3.5.8 Other operations refer to normal shutdown.

1.3.6 Precautions in the sliding pressure shutdown

1.3.6.1 Strictly follow the principle of reducing pressure first and reducing temperature second in

sliding pressure shutdown, and assign special person to monitor the reduction of steam

temperature and pressure and read meter once every 10 minutes, within which the pressure drop

must not exceed 0.4 MPa and temperature drop must not exceed 15℃, if not, stop reducing

pressure and temperature immediately and continue after stabilizing for a period.

1.3.6.2 Keep an identity between the initial steam and reheat steam which temperature difference

must not be more than 40 ,℃ and degree of superheat must be higher 50 ℃ so as to prevent

water hammer accident.

1.3.6.3 If discover the negative value of differential pressure increases too fast in sliding pressure

shutdown, lower the load down rate. When HP differential expansion reaches -0.1m, stop

reducing load and continue after differential expansion rises again, if the measures take no effect

and the differential expansion continues to increase, reduce the load to zero quickly and trip to

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shut down the unit. Start AC lubricating oil pump, and record the idle time and listen to the sound

of running parts after unit trips.

1.3.6.4 Closely monitor the unit vibration and metal temperature in the process of sliding pressure

shutdown, and it is strictly prohibited to release the axial-displacement protection.

1.3.6.5 Pay attention to the water level of deaerator and condenser, vacuum of condenser and

exhaust temperature that shall be normal.

1.3.6.6 After shutdown, cut off all steam and water sources inside the cylinder to prevent cold

steam and water from entering.

1.3.6.7 Pay attention to that the initial steam pressure shall not rise in the process of load down

so as to ensure the superheat degree of initial steam not lower than 50 min℃ imally, and the

initial steam temperature shall decrease steadily to prevent much fluctuation.

1.3.6.8 The governing stage temperature must not be 20℃ lower than the lower cylinder

temperature; When the temperature difference between upper and lower cylinder is higher than

35 ,℃ control the initial steam temperature more than 50 higher than the governing ℃ stage

temperature. As negative differential expansion increases, contact the boiler operator to stabilize

parameters, adjust the pressure of shaft seal and temperature to normal and pay attention to

steam puffing up at the shaft seal.

1.3.6.9 Stop sliding parameter and reduce the load to zero quickly to trip to shut down the unit in

any case as follows:

a. The unit vibrates abnormally;

b. The initial and reheat temperature are out of control, and drop for more than 50℃ within 10

minutes, it is necessary to break vacuum and shut down the unit, open the initial steam pipe and

proper drain valve.

c. HP & MP differential expansion reaches -2mm.

1.4 Precautions in unit shutdown:

1.4.1 Reinforce the monitoring of axial displacement, thrust pad temperature, bearing return oil

temperature and vibration and if there is friction sound inside the unit;

1.4.2 When discover the load fails in decreasing to zero, it is strictly prohibited to parallel the

generator off, but report to unit supervisor and take measure of closing main stop valve to reduce

the load to 0 and then shut down the unit;

1.4.3 Normal shutdown sequence shall be as per generator paralleling off- turbine tripping- -boiler

extinction.

1.4.4 Record the metal temperature of cylinder once every30 minutes since sliding pressure

shutdown start. After putting turning gear into operation, record the cylinder temperature, shaft

eccentricity, turning gear current and metal temperature once every hour until turning stops;

1.4.5 If discover exhaust temperature increases during shutdown, start the LP spray and find out

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the cause. Pay attention to exhaust temperature, cylinder temperature, condenser water level,

deaerator water level and HP & LP heater water level to prevent valves of steam, extraction and

drain system from untightness and resulting in cold steam and water entering the turbine;

1.4.6 In turning, pay attention to monitoring lubricating oil inlet temperature of all bearings that

shall be higher than 21℃, as well as indications of metal temperature of all bearings, turning gear

current and turbine cylinder temperature that shall be normal and record them once every hour;

1.4.7 Keep the turning gear and oil circulating system running for not less than 48 hours after

normal shutdown;

1.4.8 After turbine shutdown, it is prohibited to fill the condenser and heater to test leak when the

cylinder temperature is higher than 200 ,℃ If it must be conducted, work out reliable preventive

measures against sharp cooling of cylinder resulting in shaft bending that shall be approved by

the shift engineer;

1.4.9 After bypass system is stopped, check to make sure attemperating water valve is closed

tightly;

1.4.10 If there is clear friction sound inside the cylinder during turning, stop turning, but change to

15 minutes interval and turn the rotor by180°, and forced turning is not permitted;

1.4.11 When the first stage metal temperature of HP cylinder is higher than 150 ,℃ the turning

can only be stopped with approval of unit supervisor, get done with marking clearly, record the

stop time, and turn by 180° manually every 5~15 minutes according to the state of cylinder.

Turning time is required to be at least 10 times larger than the stop time prior to restart;

1.4.12 After shutdown, if the bearing or other parts require maintenance, both the turning gear

and oil circulation shall operate for more than 24 hours to keep the outlet oil temperature of oil

cooler at about 35℃, and it can stop the turning gear and cut off oil circulation after which, but it

is necessary to prolong the turning time prior to unit start;

1.4.13 For the shutdown for emergency maintenance, keep the turning gear and bearing oil

system circulation for at least more than 3 hours, after which it can stop turning and oil circulation

for 15 minutes and do not stop the oil circulation as much as possible. 15 minutes after stop, start

the turning gear to operate for 2 hours or until the eccentricity becomes stable. After which, it can

stop the turning gear and oil circulation, but the offtime shall not exceed 30 minutes, among

which, 15 minutes after stop, start the oil circulation to turn rotor by 180°. After 30 minutes

mentioned above, start the turning gear and oil circulation, and run the steam turbine over again

for 2 hours or until the eccentricity becomes stable. As long as turn the rotor by 180° every 30

minutes within the following six hours, the system will be able to be off for long. Start the oil

circulation to lubricate all bearings during the 180° turning.

1.4.14 If it is required to stop the turning gear for emergency due to unit fault, which may make

the rotor suffer from serious bending, so it must keep oil circulation for at least over 24 hours after

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shutdown to prevent bearing from overheating, and keep the outlet oil temperature of oil cooler

within 21~35℃ during which;

1.4.15 If the rotor bending is not very serious, it can be rotated to become straight by 1~2 hours

turning.

PART 5 Treatment of Unit Accidents

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1. Treating Rules of Accidents

1.1 In case of accident, the unit supervisor shall lead all staff of the unit to treat the accident

according to the rules quickly under direct leadership of shift engineer. If the company of unit

supervisor is harmful to person and equipment directly, the operator on duty shall explain the

reason and refuse to execute it.

1.2 If case of fault, the operator shall eliminate the danger to person and equipment and find out

the cause for the fault and remove it, at the same time shall keep non-faulted equipment

operating normally.

1.3 If case of fault, the operator shall ensure normal operation of the auxiliary power system.

1.4 Once concluding that the equipment has fault according to the instrument indication, CRT

display, and alarming of alarm window, faulted copier and appearance of unit, the operator shall:

Eliminate the danger to person and equipment and parallel off the faulted equipment immediately

if necessary;

Ascertain the nature, site and scope of fault quickly, and give treatment and report thereafter;

Ensure normal operation of the equipment without any fault;

Report to the unit supervisor as soon as possible in each stage of fault elimination for the

purpose of timely report and taking correct measures to prevent spread of accident.

1.5 Treat the accidents quickly and correctly, repeat the orders after receiving during treating the

fault; report to the staff who gives you the order after the order is conducted

1.6 When accidents and faults which are not included in the Rules occur, the staff on duty shall

take measures to treat it immediately according to their own judgment. If possible, report to the

unit supervisor and treat the accidents under the leadership of unit supervisor.

1.7 After the fault is treated through, and the cause is found out, it shall restore the operation of

unit as soon as possible and keep each parameter within permitted range during operation.

1.8 In treatment of accidents and faults, trip manually if the emergency shutdown condition is met

but the protection refuses to operate; if an auxiliary equipment reaches the emergency shutdown

condition but the protection refuses to operate, it shall shut down this auxiliary equipment

immediately.

1.9 When any fault occurs, the main operator on duty shall participate in the work of eliminating

the fault and advise the unit supervisor or shift engineer first as much as possible, and report the

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measures he has taken to the unit supervisor, and must obey all correct orders from the unit

supervisor.

1.10 The operator shall not leave the post in the process of treatment of fault and accident, If the

fault occurs during work shift, it postpone the time of shift, the staff to hand over shall go on

working and eliminate the accident with assistance by the staff to take over until the unit recovers

normal operation or receiving the order about shift from the unit supervisor.

1.11 People irrelevant to the accident shall not stay at the spot.

1.12 After treatment of fault and accident, the staff on duty shall report the time, phenomenon,

reason, development and the treatment process to the shift engineer and keep detailed records,

and the meeting it after work shift shall analyze the fault.

1.13 First make every effort to eliminate the danger to personal and equipment safety in case of

accident.

1.14 Strive to keep normal running of non-faulted equipment.

1.15 Prevent wrong judgment or treatment caused by bad contact, uncertain condition and

inaccurate report.

2. Condition of Steam Turbine Tripping

2.1 When the rotating speed of the unit increases to 3,300~3,360r/min (electric overspeed and

mechanical overspeed);

2.2 HP & MP differential expansion reaches 8 mm or -3mm;

2.3 The LP differential expansion reaches +7.5 mm;

2.4 The axial displacement reaches ±1.2mm;

2.5 The back pressure of condenser reaches 20.3KPa;

2.6 The lubricating oil pressure decreases to 0.06MPa;

2.7 The bearing vibration reaches 0.254mm;

2.8 Metal temperature of journal bearing #1~3 reaches 112 ; metal temperature℃ of journal

bearing #4~5 reaches 80 ;℃ metal temperature of thrust bearing reaches 107℃.

2.9 The EH oil pressure decreases to 9.31MPa;

2.10 DEH system power failure;

2.11 The main protection of generator operates;

2.12 The boiler MFT operates;

2.13 LP exhaust temperature reaches 121 ;℃

2.14 The oil level of main oil bank decrease to 1245mm.

3. Condition of Unit Fault Shutdown

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3.1 Fault in the main oil pump or much vibration in the speed governing system;

3.2 In the case where the initial and reheat steam temperature on turbine side increases to above

545℃ and cannot recover after running for 30 minutes; where the temperature continues to rise

to 555℃ and cannot recover within more than 15 minutes; or where the temperature exceeds

565 ;℃

3.3 The initial steam pressure increases to above 14.71Mpa;

3.4 The back pressure of conderser reaches 20.3KPa or circulating water interrupts;

3.5 The steam turbine rejects load to 0 to run for more than 15 minutes;

3.6 The change in frequency is lower than 46HZ;

3.7 The initial and reheat steam and feed water pipe or valve breaks to endanger the equipment

safety;

3.8 The MFT operates, but the major interlock of turbine-boiler refuses to operate;

3.9 The main stop valve, governing valve and MP combined valve are jammed and cannot

recover;

3.10 LP cylinder exhaust temperature reaches 121℃;

3.11 The steam turbine motor operates for more than 1 minute;

3.12 When an important monitoring meter displays inaccurately or fails, it must stop running in

the condition that there is not any effective monitoring means;

3.13 The copper tube of condenser breaks resulting a great deal of circulating water entering the

steam side.

4. Condition of Emergency Shutdown

4.1 The unit vibrates severely suddenly;

4.2 Obvious metal friction sound occurs inside the steam turbine;

4.3 The steam turbine has water hammer and the initial and reheat steam temperature decreases

by 50 ℃ within ten minutes;

4.4 Inside of shaft seal sparkles;

4.5 The generator smokes and catches fire;

4.6 Any bearing goes without oil or smokes;

4.7 Turbine bearing return oil temperature reaches 75 ;℃

4.8 Metal temperature of journal bearing #1~3 reaches 113℃; metal temperature of journal

bearing #4~5 reaches 80 ;℃ metal temperature of thrust bearing reaches 107℃;

4.9 The bearing lubricating oil pressure decreases to below 0.06MPa and cannot recover even by

starting the auxiliary oil pump;

4.10 The steam turbine oil system catches fire to endanger safe operation of the unit;

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4.11 The oil level of main oil tank decreases sharply that cannot recover by make-up oil and

decreases to the limit value;

4.12 The oil pump pipe broke and cannot be isolated, which resulting serious leak of oil to

endanger the safety of equipment;

4.13 The rotating speed of steam turbine increases to 3,300r/min, but the emergency governor

refuses to operate;

4.14 The HP & MP differential expansion reaches +8 or -3mm and LP differential expansion

reaches +7.5mm;

4.15 The axial displacement reaches ±1.2mm, and at the same time the temperature of thrust

bearing increases sharply.

5. Procedure of Emergency Shutdown with Vacuum Broken

5.1 Press the “emergency shutdowm” button or push the emergency governor handle locally with

hand to check if the HP & MP main stop valve, speed governing valve, extraction check valve and

HP exhaust check valve are closed tightly immediately and the rotating speed shall decrease;

5.2 It is prohibited to open the HP & LP bypass;

5.3 Release the starting oil pump interlocking and start the lubricating oil pump;

5.4 Ensure generator has paralleled off;

5.5 Release the vacuum pump interlocking and stop the vacuum pump to open wide the vacuum

breaker valve;

5.6 Adjust the steam seal pressure to prevent the cold air from cooling cylinder and rotor;

5.7 Open the water drain valves of steam turbine proper and all extraction pipes and it is strictly

prohibited for the cold water and cold steam in all steam and water pipes to flow inversely to the

cylinder;

5.8 Listen to the sound of the inside of unit and pay attention to the idle time and vibration of unit

rotor and keep records.

5.9 When the rotating speed decreases to 1,500r/min，start the jacking oil pump;

5.10 When the rotor stops, record the eccentricity and put the turning gear into operation, if fail in

putting it into operation, it shall turn the rotor by 1800 every 5 minutes, If there is any friction

between stator and rotor and the rotor can not be turned, report to the shift engineer and it must

not turn forcedly;

5.11 Other operations as per the specifications for normal shutdown.

6. Procedure of Unit Fault Shutdown without Vacuum Broken

6.1 Report to the unit supervisor and reduce the load to zero;

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6.2 Press the “emergency shutdowm” button or push the emergency governor handle locally with

hand to check if the if the HP & MP main stop valve, speed governing valve, extraction check

valve and HP exhaust check valve are closed and if the rotating speed of unit decreases;

6.3 Release the starting oil pump interlocking and start the lubricating oil pump;

6.4 If boiler MFT operates, treat it according to MFT operation emergency shutdown;

6.5 Adjust the steam supply pressure of deaerator and shaft seal, and switch to the standby

steam source in time;

6.6 Check thoroughly, listen to the sound of unit and record the idle time;

6.7 Other operations as per normal shutdown procedure.

7. Decreasing of Vacuum

7.1 Phenomenon

7.1.1 The condenser vacuum indication decreases, local vacuum gauge, DEH or DCS displays

vacuum decreasing;

7.1.2 The exhaust temperature of steam turbine rises;

7.1.3 “Conderser Vacuum Low “sound & light alarms.

7.2 Cause

7.2.1 The circulating water pump works abnormally and the system valve is operated by mistake,

which result in interruption or lack of circulating water;

7.2.2 The steam supply of shaft seal is not enough or shaft seal carry-over;

7.2.3 The water level of condenser is too high;

7.2.4 The vacuum pump works abnormally;

7.2.5 The vacuum system leaks or the system valve is operated by mistake;

7.2.6 The condenser piping is dirty;

7.2.7 The water temperature of vacuum pump is high;

7.2.8 No level or overfeed of water of the shaft seal heater.

7.3 Treatment

7.3.1 If discover the condenser vacuum decreasing, check the exhaust temperature immediately

to ascertain vacuum down;

7.3.2 If the condenser vacuum decreases, it shall start the standby vacuum pump rapidly to

observe the change in vacuum;

7.3.3 If the vacuum keeps on decreasing, it shall reduce the unit load appropriately until alarm off,

find out the cause and give treatment;

7.3.4 Check the operation of circulating water pump:

a. Check if the circulating water pump operates normally, otherwise switch to the standby

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circulating pump or start another pump, when there are two pumps operating, if one pump stops

for fault to result in decreasing of condenser vacuum, it shall close the outlet valve of faulted

pump quickly;

b. Check the outlet valve of circulating water pump, and open it in time if it is closed by mistake;

c. Check if the circulating water pressure is normal, if it is low, check if the circulating water

system leaks or is blocked;

d. Check the differential pressure between the circulating water outlet and inlet of condenser is

normal, if it is high, then clean a half of condenser;

e. Check if the disc valve of condenser inlet & outlet is closed by mistake; if so, open it

immediately;

7.3.5 Check the shaft seal system:

a. If the shaft seal header pressure is low, then check if the shaft seal steam source and overflow

valve are normal to adjust the shaft seal header pressure to normal;

b. If the steam pressure of LP shaft seal is low, then turn down the shaft seal attemperator spray

isolating valve and adjust the LP shaft seal steam temperature at 149℃;

c. If the shaft seal heater pressure is high, then start the standby shaft seal heater blower to

check if the multi-stage water seal of shaft seal heater is broken and water level is normal.

7.3.6 Check if the water level of condenser condensation sump is high, if so, it shall find out the

cause and give treatment;

7.3.7 Check if the LP extraction flange and junction plane of LP cylinder leak, if the vacuum

system is tight, in the case where the vacuum system leaks, seal it off and contact with

maintenance personnel to treat;

7.3.8 Check if the vacuum breaker valve is opened by mistake

7.3.9 Check if any vacuum valve and flange leaks;

7.3.10 Check if the water level of vacuum pump steam-water separator is normal and if the

vacuum pump water temperature is normal;

7.3.11 When the back pressure of condenser reaches 20.3KPa, the steam turbine shall trip

automatically and trip it manually, and give treatment according to the procedure of fault

shutdown.

8. Water Hammer of Steam Turbine

8.1 Phenomenon

8.1.1 The temperature difference between upper and lower cylinder of turbine is high;

8.1.2 Increasing of axial displacement, vibration, differential expansion are displayed, and the

sound of steam turbine is abnormal;

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8.1.3 Alarm because of abnormal water level of heater;

8.1.4 The initial steam and reheat steam pipe or the extraction pipe vibrate, shaft seal has water

hammer sound, and there is white steam belching from the main stop valve and speed governing

valve lever, as well as the flange of extraction pipe;

8.1.5 Temperature of initial and reheat steam decreases sharply;

8.1.6 Temperature of LP shaft seal header decreases sharply.

8.2 Cause

8.2.1 The boiler drum is overfed with water;

8.2.2 The steam drum pressure drops sharply, which result in the carry-over;

8.2.3 Adjustment of the boiler steam temperature is inappropriate;

8.2.4 When the unit is started, the drainage of turbine proper, shaft seal system and all relevant

steam pipes are not smooth;

8.2.5 The heater leaks or drainage is not smooth and deaerator is overfed water;

8.2.6 The unit load changes abruptly;

8.2.7 Boiler water is unqualified or carry-over (priming);

8.2.8 The attemperating water valve of bypass system is not closed tightly;

8.2.9 When the superheat degree of initial steam and reheat steam is low, the speed governing

valve swings severely.

8.3 Treatment

8.3.1 Open the drain valves of steam turbine proper and the relevant steam pipes to intensify

proper drainage;

8.3.2 If water flowing into the steam turbine is caused by water overfeed of heater, it shall stop

the overfed heater and isolate it to drain water;

8.3.3 In case of white steam belching from the main and reheat steam pipe flange, and main stop

valve and governing valve lever, treat according to fault shutdown;

8.3.4 Record the idle time of turbine and listen to the sound of inside of turbine in idling carefully;

8.3.5 Put the turning gear into operation after the turbine come to rest, it shall execute the

stipulations for turning gear operation in shutdown strictly, and intensify proper drainage;

8.3.6 After turbine shutdown caused by water emergency, it can only restart the turbine after the

unit is normal through check, temperature difference between upper and lower cylinder is<50℃,

and rotor eccentricity <0.076mm with approval of the chief engineer;

8.3.7 In the process of the start, it shall pay attention to monitoring the axial displacement,

vibration and bearing temperature, etc. parameters and drainage of relevant stem pipes of the

turbine proper, if any abnormal sound or stator-rotor friction in the process of restart, it shall break

the vacuum to shut down immediately;

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8.3.8 In case of water flowing into the turbine, if the axial displacement, differential expansion and

bearing temperature reach the tripping value, idle time shortens obviously, or there is any

abnormal sound inside the turbine, it shall shut down to check.

9. Increasing of Axial Displacement

9.1 Phenomenon

9.1.1 It gives an alarm when the axial displacement is larger than ±1mm;

9.1.2 Thrust pad temperature increases sharply, and the return oil temperature increases;

9.1.3 Vibration of the unit increases;

9.1.4 The differential expansion indication changes correspondingly.

9.2 Cause

9.2.1 The initial steam conditions decrease, and the through-flow part is overloaded;

9.2.2 The unit rejects load abruptly;

9.2.3 Water hammer occurs to the steam turbine;

9.2.4 Vacuum decreases greatly

9.2.5 The thrust pad is worn and oil interrupts;

9.2.6 The steam quality is unqualified and the stator blade scaled seriously.

9.3 Treatment

9.3.1 If the axial displacement increases, check the thrust pad temperature and return oil

temperature of thrust pad immediately and verify the increase of axial displacement, report to the

unit supervisor to request for reducing the load appropriately so as to make the axial

displacement, return oil temperature and thrust bearing temperature recover;

9.3.2 Check that the pressure of the monitored section that shall not be higher than the specified

value; Or else report to the unit supervisor to request for reducing the loading;

9.3.3 If the axial displacement increase is caused by initial steam conditions exceeding the limit,

it shall adjust the boiler combustion to remover normal conditions;

9.3.4 If the load reduction takes no effect, and the axial displacement reaches ±1.2mm and

protection operates, it shall treat according to the emergency shutdown;

9.3.5 It shall shut down the turbine for emergency if the thrust pad oil interrupts or any point

temperature exceeds 107℃ and return oil temperature exceeds 75℃;

9.3.6 It shall shut down the turbine for emergency when the unit vibration exceeds limit due to

broken blade and water hammer;

9.3.7 It shall shut down the turbine for emergency if the protection refuses to operate when the

axial displacement increases to the limit value.

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10. Steam Turbine Oil System Catching Fire

10.1 Phenomenon

10.1.1 The fire monitor control raises the alarm;

10.1.2 Flare or smoke is discovered locally;

10.1.3 When the turbine oil pipe leaks, the oil level of main oil tank decreases;

10.1.4 When the lubricating oil system leaks, lubricating oil pressure decreases, signal

“Lubricating Oil Pressure Low” may be raised and AC & DC lubricating oil pump may interlock

start.

10.2 Cause

10.2.1 Oil system leaks;

10.2.2 Oil leaks to high temperature hot body or faulted electrical equipment;

10.2.3 Oil pipe is broken due to external causes and oil leaks to the hot body.

10.3 Treatment:

10.3.1 If any abnormal change in the oil level of main oil tank and all oil pressure, it shall find out

the cause, if due to oil leak of oil system, it shall ascertain the leaking point and try to isolate it

from surrounding hot body pat and operating equipment to prevent the oil system from catching

fire, meanwhile, contact the maintenance personnel to treat the leaking point temporarily;

10.3.2 If the equipment and pipe of unit oil system is damaged to leak, in any case where the

equipment or pipe cannot be isolated from system to be treated or oil has seeped into the heat

distribution pipe, it shall shut down to treat immediately;

10.3.3 After the system catches fire, it shall cut of the equipment power supply endangered by

the fire, and then extinguish the fire and advise the fire fighter immediately;

10.3.4 If the fire cannot be extinguished quickly and endangers the personal and equipment

safety, it shall break the vacuum to shut down for emergency immediately. Release the

interlocking of starting oil pump, not start the starting oil pump to shut down the lubricating oil

pump; if the lubricating oil system catches fire that cannot be extinguished, resulting in shutdown,

it may reduce the lubricating oil pressure to decrease oil leak in the precondition of ensuring

normal lubrication of bearing.

10.3.5 When the fire endangers the main oil tank or top platform, plant building and neighboring

turbine, after tripping to shut down, it shall open the emergency oil drain valve of main oil tank,

keep mini permitted oil level prior to the rotor coming to rest and drain out the remaining oil after

rotor coming to rest.

11. Abnormity of Steam Conditions

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11.1 Steam temperature does not change, but the initial steam and reheat steam pressure

become abnormal.

11.1.1 Phenomenon

a. Initial steam and reheat steam pressure gauge change;

b. DEH and DCS display the initial steam and reheat steam pressure alarm;

c. When the unit operating in coordinated control mode, its load changes correspondingly.

11.1.2 Cause

a. Fault in control system;

b. Unit’s load changes abruptly.

11.1.3 Treatment

a. If it is the fault in control system that caused abnormality of initial and reheat steam

pressure, it shall adjust the charge of fuel to restore the initial and reheat steam pressure;

b. If it is the too quick change of unit’s load that caused abnormality of initial and reheat

steam pressure, it shall try to stabilize the load and change it after the initial and reheat

steam pressure recovering;

c. If the initial and reheat steam pressure are high, it may increase the unit’s load to make

the pressure recover;

d. When the initial steam pressure rises up to 14.71Mpa, it shall trip to shut down the turbine;

e. When the initial and reheat steam pressure change, it shall pay attention to the unit’s

vibration, sound, differential expansion and axial displacement, as well as temperature

difference between upper and lower cylinder of turbine;

f. When the steam pressure drops, it shall control each monitored section pressure not

exceeding the max permitted value with initial steam flow rate>P440t/h;

g. If the steam pressure keeps on dropping to below 4Mpa and cannot recover, treat

according to fault shutdown.

11.2 Steam pressure does not change, but the initial steam and reheat steam temperature

become abnormal.

11.2.1 Phenomenon

a. Initial steam and reheat steam temperature gauge change;

b. DEH and DCS display the initial steam and reheat steam temperature alarm.

11.2.2 Cause

a. Governing of attemperator to the initial steam and reheat steam fails;

b. Boiler steam drum is overfed with water;

c. Boiler combustion is unstable and combustion condition changes;

d. Unit’s load changes greatly;

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e. Coking or soot deposit of furnace;

f. In soot blowing of boiler;

g. Coal quality changes.

11.2.3 Treatment

a. If Auto mode of the initial steam and reheat steam attemperator fails, it shall adjust

manually to keep initial steam temperature not exceed 545℃;

b. Check the water level of steam drum and adjust the water level to normal;

c. If the boiler combustion rate is high, which caused initial and reheat steam temperature

becoming high, it shall reduce the load at the same time of reducing coal;

d. In the case where initial and reheat steam temperature exceed 545℃ and cannot recover

after running for more than 30 minutes; where the temperature continues to rise to 555℃

and cannot recover within more than 15 minutes; or where the temperature exceeds 565 ,℃

treat according to fault shutdown;

e. Temperature difference between the left and right of initial steam and reheat steam

temperature shall be less than 17℃;

f. When the initial steam and reheat steam temperature change in operation, it shall pay

attention to the unit’s vibration, sound, differential expansion and axial displacement, as well

as temperature difference between upper and lower cylinder of turbine;

g. When the initial steam temperature decreases to 500℃, it shall open drain valves of the

turbine proper and initial steam conduit and intensify monitoring of metal temperature, axial

displacement and thrust pad temperature;

h. In the case where initial steam temperature decreases by 30℃ within 10min, it shall open

the drain valves of initial steam & reheat steam pipe and proper, report to the unit supervisor

and closely monitor the unit’s vibration, axial displacement and differential expansion;

i. In the case where the steam temperature decreases by more than 50℃ within 10min, it

shall trip to shut down the turbine immediately;

j. In the case where initial steam temperature decreases suddenly and superheat degree of

steam decreases to below 150℃, it shall trip to shut down the turbine immediately.

11.3 Steam temperature and pressure decrease at the same time.

11.3.1 If the steam temperature and pressure decrease at the same time, it shall verify the

superheat degree and meanwhile restore steam conditions quickly, if fail, report to the unit

supervisor, reduce load and pay attention to monitoring the change in differential expansion and

axial displacement;

11.3.2 When the steam temperature decrease to the value under corresponding pressure and

superheat degree is not enough, it shall shut down the turbine for fault immediately;

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11.3.3 Closely monitor if there is white steam belching or water drop spilling from the main stop

valve, shaft seal and junction plane of cylinder, if any water hammer, it shall shut down the

turbine for emergency. Closely monitor the change in metal temperature and differential

expansion;

11.3.4 Pay attention to the change in shaft seal pressure and water level of condenser and all

heaters, switch over the steam source of deaerator in time;

11.3.5 When the initial steam temperature and pressure decrease at same time, although not to

the shutdown temperature, the initial steam temperature is over 50℃ lower than the first stage

metal temperature, it shall report to the unit supervisor and request for fault shutdown.

12. DEH Failure

12.1 Phenomenon

12.1.1 “DEH Power Failure” light and sound alarm is raised;

12.1.2 DEH displays “Main Power Supply Failure” and “Standby Power Supply Failure”;

12.1.3 DEH displays “DEH failure” and the indicator lamp lights;

12.1.4 The indicator lamp of “Operator Auto” on DEH operating panel goes out;

12.1.5 The indicator lamp of “Manual” on DEH operating panel lights;

12.1.6 DEH displays “Speed Failure”.

12.2 Cause

12.2.1 Computer’s AC power off;

12.2.2 Fault in computer or VCC card;

12.2.3 Two of DEH speed feedback channels get fault in increasing and decreasing the speed of

turbine (extensive speed control).

12.3 Treatment

12.3.1 If it is required to change the load or rotating speed, operate the "GV UP” and “GV Down"

manually and observe the change in speed or load via the "Speed" or "Power" window.

12.3.2 Pay attention to monitor if the changes in turbine lubricating oil temperature, bearing return

oil temperature, axial displacement, differential expansion and vibration are within normal range.

12.3.3 If DEH power off, turbine should trip automatically, and otherwise it shall trip it manually;

12.3.4 If DEH failure caused main stop valve or HP governing valve on one side closing, it shall

shut down the turbine immediately.

13. Abnormity of Steam Turbine Lubricating Oil System

13.1 Main phenomena of the abnormity of oil system:

13.1.1 Main oil pump operates abnormally;

13.1.2 Oil leakage of the equipment and oil system;

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13.1.3 Foreign matters dropped into the oil pipe and the strainer is dirty;

13.1.4 Lubricating oil system valve element dropped out;

13.1.5 Auxiliary oil pump operates abnormally;

13.1.6 Too low oil level of the oil tank;

13.1.7 Oil system catches fire.

13.2 Fault in the main oil pump

13.2.1 Phenomenon

a. Outlet oil pressure decreases;

b. Sound in the unit’s head is abnormal;

c. When the case becomes serious, the starting oil pump starts to operate automatically and

the alarm window raises an alarm.

13.2.2 Treatment

a. The starting oil pump shall start to operate automatically when the oil pressure decreases

to 0.883MPa, otherwise start it immediately and check if the inlet oil pressure of main oil

pump and stage I oil injector are normal;

b. Listen to the sound of main oil pump carefully, closely observe the change in system oil

pressure and report to the unit supervisor;

c. Ascertain the fault in main oil pump and treat according to emergency shutdown with

vacuum broken.

13.3 Oil pressure decreases, but oil level does not change.

13.3.1 Cause

a. Check valves of the staring oil pump and AC & DC lubricating oil pump are untight;

b. Oil injector and main oil pump operate abnormally;

c. The outlet strainer of the oil cooler is blocked;

d. Overpressure valve is adjusted improperly or spring is broken;

e. Internal leak between oil supply system and oil return system.

13.3.2 Treatment:

a. When the oil pressure decrease to 0.883Mpa, the starting oil pump should start

automatically, otherwise start it manually;

b. Check the cause of oil pressure being low and if the speed governing system operates

normally;

c. Check if the indication of oil tank’s oil level gauge is normal;

d. Check the return oil quantity of each bearing, if the return oil quantity of bearing #1

increases, it indicates the speed governing oil pump or main oil pump seal ring in this

bearing box leaks oil;

e. If there is any lubricating oil pressure decreases, when the oil pressure decreases to

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0.07Mpa, the AC lubricating oil pump should start to operate automatically, otherwise start it

manually to increase the lubricating oil pressure;

f. Switch the lubricating oil strainer, and operate and check if the stage Ⅱoil injector is

blocked.

g. If the overpressure valve operates by mistake, contact the maintenance personnel to treat;

h. If the lubricating oil pressure still decreases to 0.06MPa, the DC lubricating oil pump

should start to operate automatically, otherwise start it manually;

i. The lubricating oil pressure still decreases to 0.06MPa even if various measures, it shall

break the vacuum for emergency shutdown.

13.4 The oil pressure does not change, while oil level decreases:

13.4.1 Cause:

a. Oil leak in the return oil pipe of the oil cooler, oil system or oil catch of bearing;

b. Emergency oil drain valve, oil drain valve of oil tank, sampling valve or water discharging

valve etc. leak or opened by mistake;

c. Oil gauge malfunctioned;

d. If the oil pump packing set leaks oil seriously.

13.4.2 Treatment:

a. Check if the indication of the oil level gauge of oil tank is right;

b. Check if the emergency oil drain valve and sampling valve etc. leak or opened by mistake;

c. Check the leak of the running oil cooler, if any, it shall switch over to others.

d. Check if there is oil leak of oil system pipe completely, if any, try to eliminate the leak and

take strict precautions against oil leaking to high temperature pipe and equipment;

e. When the oil level of oil tank decreases to 1,800mm, it shall contact the maintenance

personnel to service and make up oil in time;

f. When oil level decreases to 1,245mm, if any means takes no effect, it shall break the

vacuum for emergency shutdown.

13.5 Oil pressure does not change, which oil level rises:

13.5.1 Phenomenon & cause:

a. Great steam leakage of shaft seal and too wide clearance of main bearing oil catch

caused water mixed in oil;

b. Oil cooler leaks, and the pressure of water side is higher than that of oil side.

13.5.2 Treatment

a. Check if the indication of the oil level gauge is right;

b. Discharge the water from the bottom of oil tank, if the water quantity is high, it shall advise

the chemical staff to assay the oil quality and filter the oil if necessary;

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c. Adjust the steam inlet pressure and flow of shaft seal;

d. Switch over the oil cooler to check leaks;

e. Ascertain the cause of water flowing into oil system then eliminate it.

13.6 Oil pressure and level decrease at the same time.

13.6.1 If the oil supply system leaks seriously, it shall report to the unit supervisor to try to stop

the leak and take measures against fire, change the direction of oil leakage to keep it off the hot

body if necessary, meanwhile advise the maintenance personnel to make up oil of oil tank and

eliminate the defect;

13.6.2 Check if the oil and water discharge valves are on closed position;

13.6.3 Check leak of the oil cooler, if any, it shall switch to the standby oil cooler in time;

13.6.4 If the bearing oil inlet pressure decreases to below 0.06Mpa or oil level decreases to

1,245mm due to a great deal of oil leak, it shall start the lubricating oil pump immediately to break

the vacuum for emergency shutdown.

13.7 The return oil temperature of bearing rises

13.7.1 Cause

a. The outlet oil temperature of the oil cooler rises;

b. The lubricating oil pressure decreases or the oil inlet pipe of bearing is blocked;

c. The bearing pas is damaged and inlet hole is blocked;

d. Much vibration of the unit;

e. The steam turbine is overloaded and axial thrust is excessive;

f. The oil quality decreases.

13.7.2 Treatment

a. When the return oil temperature of bearing rises by 2~3℃ suddenly, it shall find out the

cause and take corresponding measures;

b. When the return oil temperature of all bearings rises, it shall check if the oil outlet

temperature of oil cooler and lubricating oil pressure are normal;

c. When the return oil temperature of only one bearing rises, it shall check the inlet oil

pressure and return oil flow of this bearing, as well as bearing vibration and axial

displacement change, and report to the unit supervisor;

d. When the thrust bearing pad temperature rises to 80 ,℃ report to the unit supervisor and

find out the cause, if the temperature keeps on rising to 90 ,℃ report to the unit supervisor to

lower the oil outlet temperature of oil cooler and load appropriately, meanwhile pay attention

to the axial displacement and return oil temperature of thrust bearing pad.

e. When any bearing oil interrupts or smokes or bearing return oil temperature rises up to

75 sharply, it shal℃ l break the vacuum for emergency shutdown.

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13.8 Fault in auxiliary oil pump:

13.8.1 In the process of unit start, it shall treat the fault in the starting oil pump as follows:

a. When the rotating speed of steam turbine reaches below 2500rpm, start the lubricating oil

pump immediately, trip to shut down the turbine, and it can only restart the turbine after

removing the fault in the starting oil pump;

b. When the rotating speed of steam turbine reaches above 2500rpm, it shall start the AC

lubricating oil pump at once, if the main oil pump is able to maintain normal oil pressure,

increase the speed up to 3,000rpm quickly, stop and service the starting oil pump, it can only

restart after removing the fault in the starting oil pump.

13.8.2 Treatment of fault in the auxiliary oil pump in the process of unit shutdown:

a. If it is the AC lubricating oil pump that gets fault, start the starting oil pump or DC

lubricating oil pump immediately to make shutdown continue;

b. If all three oil pumps get fault: it shall start the jacking oil pump immediately to break the

vacuum for emergency shutdown.

14. Abnormal Vibration of the Unit

14.1 Phenomenon

14.1.1 The vibration indication on DEH panel increases;

14.1.2 The unit sends out abnormal sound, and lubricating oil pressure and temperature may

become abnormal;

14.1.3 Bearing vibrates sharply and the sound-light alarm is raised;

14.1.4 Bearing vibration increases as measured locally.

14.2 Cause

14.2.1 The oil temperature is abnormal, resulting in oscillation of oil film;

14.2.2 Oil flowing into the bearing pad is insufficient or interrupted, resulting in damage to oil film;

14.2.3 Unit load and steam conditions change abruptly;

14.2.4 The opening extent of the main stop valve and governing valve are different between side

A and B, deviation of steam flow is great;

14.2.5 Expansion on both sides of cylinder is uneven;

14.2.6 The sliding key system is jammed;

14.2.7 High metal temperature difference of cylinder resulted in heat distortion or bending of

shaft;

14.2.8 Shaft seal is damaged or shaft end is cooled, result in bending of shaft;

14.2.9 Breakdown of blades and deformation of diaphragm;

14.2.10 The rotor components become loose or the rotor is unbalanced;

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14.2.11 The thrust pad is damaged, axial displacement increases or bearing bush clearance is

unqualified;

14.2.12 The generator rotor is not heated equally.

14.2.13 The running components in the front bearing case fall off.

14.2.14 Center of the turbine-generator is abnormal, or the rotor bending is relatively large and

exceeds the specified value as starting.

14.2.15 Condenser vacuum is low;

14.2.16 The generator exciter caused the vibration;

14.2.17 Anchor bolts of all bearing bushes of the turbine-generator unit become loose;

14.2.18 Oil contains foreign matters that wear the bearing bush tungsten-base alloy or water mix

in oil and oil is emulsified.

14.3 Treatment

14.3.1 The unit vibrates sharply suddenly, or metal sound inside the unit can be heard clearly, it

shall break the vacuum for emergency shutdown quickly.

14.3.2 Abnormal vibration occurs during operation:

a. When discovering the bearing vibration increases gradually, if the rotor vibration exceeds

0.08mm or bearing vibration exceeds 0.03mm, it shall report to the unit supervisor to try to

eliminate the vibration, if the rotor vibration exceeds 0.254mm, it shall shut down

immediately;

b. If the unit sends out impulsive sound from the inside in operation or the conductivity of

condensate increases suddenly, the monitored section pressure at same load rises and

vibration increases obviously, it shall immediately break the vacuum for emergency

shutdown;

c. When the shaft vibration changes by 0.05mm or bush vibration changes ±0.03mm, it shall

find out and try to eliminate the cause, when the bearing vibration change increases to

0.015mm suddenly, it shall trip and shut down the unit immediately;

d. When the load changes, it shall reduce the load until vibration disappears;

e. If it fails in ascertaining the vibration cause directly, it shall take measures to reduce the

load, If the vibration or abnormal sound remains, report to the unit supervisor and relative

leaders for settlement.

14.3.3 Abnormal vibration occurs during start-up and shutdown:

a. In the case where rotor eccentricity at a speed of below 600r/min or bearing vibration

exceeds 0.03mm at a speed of below 1200r/min in the process of start-up speed rise, it shall

trip and shut down the unit immediately. When the unit operates at critical speed, if the

bearing vibration exceeds 0.10mm or shaft vibration exceeds 0.25mm, it shall trip and shut

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down the unit immediately. It is prohibited to warm up with critical speed or reduction of

speed forcedly. It can only restart the unit after ascertaining and removing the cause;

b. It shall cease the start-up when there is friction at end shaft seal or through-flow parts,

report to the unit supervisor and relative leaders, it can only restart the unit after finding out

the cause;

c. In the process of shutdown, if friction sound inside the end shaft seal or cylinder can be

heard clearly, it shall break the vacuum for emergency shutdown;

d. In the case of shutdown due to abnormal vibration, it shall pay attention to the idle time

and listen to the inner sound of the unit carefully and increase the time of continuous turning.

15. Generator parallels off, while turbine does not trip

15.1 Phenomenon

15.1.1 Load reaches 0, generator parallels off, all extraction check valves close and make

signals;

15.1.2 The electric overspeed OPC protection operates, after closing, HP & MP speed governing

valves open to no load position, and the speed decreases to about 3,000r/min;

15.1.3 Running sound of the turbine changes suddenly and the speed rises.

15.2 Treatment

15.2.1 Adjust the speed to keep the unit at 3,000r/min;

15.2.2 Close and check all electric extraction valves;

15.2.3 Keep the water level of deaerator normal, close extraction 3 motor-operated valve, change

the steam source of deaerator to be supplied by the neighboring turbine, adjust the water level of

condenser and check the LP cylinder spray that shall put into operation;

15.2.4 Switch over the steam supply of shaft seal in time;

15.2.5 If all parts of the unit are normal through a thorough check, report to the unit supervisor

and parallel the generator in with load on;

15.2.6 If the generator fails in paralleling in within 15min after rejection of load, it shall shut down

the unit for fault.

16. Generator parallels off and turbine trips

16.1 Phenomenon

16.1.1 Load reaches 0, generator parallels off and emergency governor operates;

16.1.2 HP & MP main stop valve, speed governing valve, all extraction check valves and HP

exhaust check valves closed, unit sound changes abruptly and speed rises and then decreases;

16.1.3 The initial steam pressure rises, steam flow meter indication approaches zero.

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16.2 Treatment

16.2.1 When the speed decreases to 3,000r/min, release the interlocking of starting oil pump and

start the lubricating oil pump;

16.2.2 Pay attention to adjusting the water level of condenser and HP & LP heater, put the LP

cylinder spray into operation;

16.2.3 Maintain the water level of deaerator and switch into standby steam source of deaerator;

16.2.4 Check the unit completely and switch the steam supply of shaft seal to the standby;

16.2.5 Record the idle time when the speed decreases to zero, and stop the steam supply of

shaft seal when the vacuum decreases to zero and put the turning gear into operation in time;

16.2.6 After shutdown, check the unit thoroughly, find out the causes of speed governing system

operating abnormally and generator paralleling off, it can only restart the unit after eliminate the

causes and unit being normal through test.

17. Turbine trips, while the generator does not parallel off

17.1 Phenomenon

17.1.1 Some protection operates and makes signals, power reaches zero or displayed in

negative;

17.1.2 HP & MP Main stop valve, speed governing valve, extraction check valve and HP exhaust

check valves closed;

17.1.3 The generator does not parallel off and speed does not change.

17.2 Treatment

17.2.1 After the protection operating, it shall cut off the outlet switch of generator-transformer unit

to parallel off and shut down, and the operating time of unit without steam shall not exceed 1

minute;

17.2.2 Check and ascertain the cause steam turbine protection operating, treat according to

emergency shutdown or fault shutdown;

17.2.3 If the protection of steam turbine operates by mistake, it shall advise the thermodynamic

engineer to find out and remove the cause quickly. If it fails within 15 minutes, it shall shut down

the unit for fault;

17.2.4 Advise the electric staff to find out and remove the non-tripping cause of generator-

transformer unit quickly;

17.2.5 After removing the fault, it can only restart the unit after it is normal through test.

18. Failure of Thermodynamic Power Supply

18.1 Phenomenon

18.1.1 The heat-control power indicator lamp goes out and the alarm window lights;

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18.1.2 The indication of instruments is abnormal and all indicator lamps go out;

18.1.3 Power failure of motor-operated valves and governing valves, and malfunction of all

automatic governing;

18.1.4 Partial protections and interlocks of the unit can not operate.

18.2 Treatment

18.2.1 Immediately contact heat engineer to recover the power supply, check and monitor primary

meters locally, and switch the automatic into manual governing;

18.2.2 Report to the unit supervisor and keep the unit load stably as much as possible;

18.2.3 Avoid adjusting as much as possible, monitor the operation of equipment according to the

indication of local meters and ammeter of each auxiliary equipment, etc., and make necessary

adjustment locally;

18.2.4 When the system or equipment becomes abnormal, and the unit loses operating and

monitoring means, which affect the safety of main equipment, report to the unit lead and conduct

fault shutdown;

18.2.5 If the heat control power supply can not recover within 30 minutes, make fault shutdown.

18.2.6 If the heat control power supply of turbine and boiler fail at the same time, it shall conduct

fault shutdown.

19. High Bearing Temperature of Turbine-generator Unit

19.1 Phenomenon

19.1.1 DEH displays that the bearing temperature is high and raises the alarm;

19.1.2 Local thermometer of bearing return oil displays high indication.

19.2 Cause

19.2.1 Lubricating oil temperature is high or pressure is low, and the oil quality is unqualified;

19.2.2 Bearing inlet & outlet oil pipes are jammed;

19.2.3 Motion and static bearing has friction between the stationary and rotary part;

19.2.4 Shaft seal leaks steam too seriously;

19.2.5 Vibration cause damage to the oil film, and the lubrication is poor;

19.2.6 Unit is overloaded or vacuum of condenser is low vacuum.

19.3 Treatment

19.3.1 If bearing temperature high alarm is raised, it shall intensify monitoring;

19.3.2 When the temperature of all bearings rises generally, if the lubricating oil pressure is low, it

shall treat according to the decreasing of lubricating oil pressure, if the lubricating oil pressure is

normal, it shall check if the state of inlet and outlet valve of oil cooler is right, and adjust the

lubricating oil temperature to normal;

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19.3.3 if the temperature of individual bearings is high, listen to if there is metal friction sound

inside the bearing and observe the condition of return oil, and lower the unit load at high

temperature alarm;

19.3.4 If the shaft seal pressure is high and the steam leak of shaft seal is serious, it shall check

the steam source governing valve of shaft seal and adjust the shaft seal pressure to normal;

19.3.5 When the temperature of journal bearing #1-3 of turbine reaches 112 ,℃ the temperature

of journal bearing #4-5 of generator reaches 80℃ and the temperature of thrust bearing reaches

107℃, the steam turbine should trip automatically; if bearing return oil reaches 80℃, it shall treat

according to emergency shutdown for fault;

19.3.6 Pay attention to adjusting the unit load and vacuum of condenser.

20. Burning out of Turbine-generator Bearing Bush

20.1 Phenomenon:

20.1.1 The bearing metal temperature rises abruptly;

20.1.2 The bearing return oil temperature rises abruptly;

20.1.3 The unit vibration increases;

20.1.4 Bearing smokes.

20.2 Cause

20.2.1 Oil in and oil return of bearing are not smooth;

20.2.2 Foreign matters falling in the bearing, and tungsten-base alloy dropped out;

20.2.3 Return oil temperature of cooler is too high or too low;

20.2.4 Oil quality deteriorated;

20.2.5 Vibrations caused crack of oil film;

20.2.6 The stress distributed to bearings is uneven and load of individual bearing is high;

20.2.7 Lubricating oil flow of the bearing is insufficient or broken;

20.2.8 Oil cooler and lubricating oil strainer are switched over improperly, which resulted in air

mixing in oil;

20.2.9 The axial thrust rises suddenly, which resulted in overload of thrust bearing;

20.2.10 The bearing has its own defect.

20.3 Treatment

20.3.1 If the metal temperature and return oil of any bearing rise of the generator unit rise

abnormally, it shall find out the cause immediately;

20.3.2 Start AC lubricating oil pump to raise the oil pressure if the lubricating oil quantity is

insufficient, check if any valve operates by mistake, if the oil level of main oil tank is normal and if

the lubricating oil strainer is blocked, meanwhile contact the maintenance personnel to check that

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if the oil injector and lubricating oil overpressure valve work normally;

20.3.3 If the lubricating oil temperature is abnormal, adjust it to normal;

20.3.4 If any bearing oil interrupts, smokes or metal temperature and return oil temperature of

bearing reach the limit, it shall break the vacuum to trip and shut down the unit immediately.

21. Steam Turbine Shaft Bending

21.1 Phenomenon:

21.1.1 Steam turbine has abnormal vibration and bearing box swags;

21.1.2 The steam seal of shaft end sparkles or form a fire ring;

21.1.3 Idle time of the bearing shortens obviously after shutdown;

21.1.4 The turning gear can not be put into operation or the turning gear current is larger than

normal value and oscillates periodically after shutdown;

21.1.5 The shaft eccentricity is large after shutdown;

21.2 Cause

21.2.1 The eccentricity of rotor exceeds the specified range before start;

21.2.2 High temperature difference between upper and lower cylinder;

21.2.3 Inlet steam temperature is low;

21.3.4 Cold water and steam enter the cylinder;

21.3.5 When unit vibration exceeds the specified value, it fails to trip and shut down the unit;

21.2.6 Rotor deflected as assembled;

21.2.7 Turning gear is abnormal or not put into operation in time after shutdown and

vacuumization.

21.3 Treatment:

21.3.1 When abnormal vibration occurs to the unit, it shall find out the cause and report to the unit

supervisor and try to eliminate the vibration;

21.3.2 When the vibration of unit reaches the shutdown value or shaft seal sparkles, it shall break

the vacuum and conduct fault immediately;

21.3.3 After shutdown, immediately put the turning gear into operation, open the drain valve of

steam turbine proper, closely monitor the temperature difference between upper and lower

cylinder, as well as turning gear current and eccentricity, etc. parameters to prevent strictly cold

water and steam from entering the steam turbine and insulate the steam turbine from outside

system reliably;

21.3.4 After shutdown, if the shaft seal rubs seriously, it shall put the high point of rotor on the

highest position, close cylinder drain, maintain the temperature difference between upper and

lower cylinder and monitor rotor bending becoming normal, thereafter operate the turning gear by

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180º manually to ascertain the rotor bending is normal, put in continuous turning, it is strictly

prohibited to turn forcedly with a crane if turning fails;

21.3.5 If it is the fault in turning gear that caused shutdown, after shutdown, it shall monitor the

change in rotor bending, when the bending is high, it shall operate the turning gear by 180º and

put the continuous turning into operation after the turning becomes normal in time;

21.3.6 After shutdown, continuous turning time must not be less than 4 hours, only after the

temperature difference between upper and lower cylinder, turning gear current, and rotor

eccentricity meeting the starting conditions, can restart the unit after reporting to the unit

supervisor, closely monitor the rotor vibration and eccentricity etc. parameters in start, if any

abnormality, trip and shut down the unit immediately.

22. Steam turbine Overspeed

22.1 Phenomenon:

22.1.1 The unit rejects the load to zero suddenly and sends out abnormal sound;

22.1.2 Rotating speed and frequency indication of the unit exceed the stipulated value and keep

on rising;

22.1.3 The outlet pressure of main oil pump and lubricating oil pressure increase;

22.1.4 Unit vibration increases;

22.1.5 OPC protection operates, and the mechanical overspeed protection and electric

overspeed protection of the unit possibly operate.

22.2 Cause:

22.2.1 DEH control system works abnormally and has defects;

22.2.2 Poor oil quality of the steam turbine makes the control and governing system refuse to

operate and loss protective function;

22.2.3 Test to the emergency governor is not done according to the stipulated conditions and

time, so the emergency governor operates to make the rotating speed change;

22.2.3 Poor steam quality and main stop valve and governing valve lever scaling result in valves

being jammed and cannot be closed;

22.2.4 Extraction steam check valve and HP check valve are out of order, drain of the high

pressure heater vaporized or steam of public system enters the steam turbine.

22.3 Treatment:

22.3.1 After the unit rejects load to zero and rotating speed reach 3,090r/min, check that HP &

MP governing valve shall be closed, try to close the unclosed if any, lower the unit’s rotating

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speed to 3000r/min or so, ascertain and eliminate the cause of load rejection within 15 minutes

and parallel the unit in, if fails, it shall conduct fault shutdown;

22.3.2 When the unit speed rises up to 3,300r/min, check that the mechanical and

electromagnetic overspeed protection shall operate. Otherwise it shall trip and shut down the unit

manually, verify that the HP & MP main stop valve and all extraction check valve shall be closed,

cut off all possible steam access to turbine and immediately open the vacuum breaker valve for

emergency shutdown;

22.3.3 If the overspeed is caused by HP & MP main stop valve being jammed, it shall

immediately start the overheater or reheater atmospheric exhaust valve, and etc. to reduce the

pressure;

22.3.4 Eliminate the cause of overspeed after the turbine is shut down for overspeed, and it can

be restarted after it is qualified through calibration, it shall intensify overall check of the unit in

restart, if any abnormality, it shall find out and eliminate the cause immediately.

23. Feed water pump set outlet check valve is untight and rotates reversely

23.1 Phenomenon:

23.1.1 Feed water pump reverses;

23.1.2 The pressure of the outlet header pipe decreases and the current of the parallel running

pump increases;

23.1.3 Sound of the reversing pump is abnormal and accompanied by increased vibration;

23.1.4 Water level of deaerator rises;

23.1.5 Water level of steam drum decreases and feed water flow decreases;

23.1.6 The oil inlet temperature of working oil cooler rises.

23.2 Treatment

23.2.1 Once discovering pump reversing, it shall close the outlet motor-operated valve and center

tap motor-operated valve of this pump immediately;

23.2.2 If the reversing feed water pump outlet motor-operated valve and center tap valve loss

power or jammed and cannot be closed, it shall stop the working feed water pump, close the

forced handwheel of HP heater outlet check valve, close the main feed water motor-operated

valve of boiler and feed water bypass motor-operated valve, press MFT to shut down the boiler

and shut down the turbine without vacuum broken;

23.2.3 In any case, the feed water pump can only be stopped after all outlet motor-operated

valves have been closed. Assign person to monitor locally if the pump reverses in the process of

stopping the pump;

23.2.4 When the feed water pump restores standby, it shall open the outlet motor-operated valve

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with hand, and verify the outlet check valve have returned prior to electric opening.

24. Turbine-generator unit operates at abnormal frequency

24.1 Phenomenon:

24.1.1 Indication of frequency meter decreases or rises.

24.1.2 Sudden change of the unit’s sound.

24.1.3 DEH shows that the indication of steam turbine speed decreases or rises.

24.1.4 Indication of power meter decreases or rises.

24.2 Cause: Fault in the electric power network system.

24.3 Treatment

24.3.1 If frequency decreases and unit load increases, it shall stabilize the unit load at the rating

as soon as possible that is not permitted to exceed max limit to load. Pay attention to that the

pressure of all monitored sections and initial steam flow shall not exceed the maximum value,

otherwise reduce the load manually;

24.3.2 Check if the initial steam conditions, vacuum, axial displacement, thrust bearing

temperature & vibration and lubricating oil pressure are normal.

24.3.3 Pay attention to the operation of each auxiliary equipment and check if any operating

equipment is overloaded to heat.

24.3.4 Strictly monitor the unit frequency not to exceed the value in the following table:

Frequency(Hz)Permitted operating time

Accumulated (min) Every time (Sec)

52.5 >5 >5

52.0 >30 >30

47.5~51.5 Continuous operation

47 >60 >60

46.5 >10 >10

46 >2 >2

24.3.5 In operation at high frequency, reduce the active output as required, pay attention to the

vibration of unit, if the vibration rises up to the tripping value, it shall conduct emergency

shutdown.

25. Boiler Fire Extinction

25.1 Phenomenon

25.1.1 MFT operates, sound & light alarm is raised;

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25.1.2 Negative pressure of furnace increases suddenly;

25.1.3 Furnace inner is dark, flame of the monitor disappears, alarm window of no fire in the

upper, middle and lower layer raised an alarm;

25.1.4 Steam’s pressure and temperature decrease sharply, the water level of steam drum first

decreases and then rises;

25.1.5 Boiler fire extinguishing, MFT operates, steam turbine trips, generator-transformer unit

parallels off the system;

25.2 Cause

25.2.1 Conditions of the MFT operation are met;

25.2.2 Auxiliary power interrupts;

25.2.3 Boiler load is too low, operation and adjustment are improper, disproportion between air

and pulverized coal, primary air speed is too high or proportioning of primary and secondary air is

improper;

25.2.4 Jet burner operates with seriously unfilled corner, coal feeder gets fault, pulverized coal

chute is blocked, level of pulverized coal is too low, which make combustion unstable that is not

adjusted and treated in time;

25.2.5 Water-cold wall pipe, economizer, superheater and reheater burst seriously;

25.2.6 Boiler has serious fouling and coke residue fall off by a large area;

25.2.7 Coal quality is too poor, volatile content is too low or coal type changes suddenly;

25.2.8 When ash is being removed, large amount of cold air enter the furnace;

25.2.9 When the combustion is unstable, fail in put oil into supporting the combustion in time;

25.2.10 During startup, oil gun gets fault and oil quality is poor;

25.2.11 Induced and forced draft blower trip;

25.2.12 Both flame monitor and cooling fan get fault.

25.3 Treatment

25.3.1 Extinguish the boiler fire and treat the unit as emergency shutdown;

25.3.2 Report to the unit supervisor, extinguish the boiler fire, if the turbine does not trip, reduce

the load to 5~20MW according to the steam pressure, keep turbine at full speed, but if the

operating time at no load exceeds 15 min, it shall trip to shut down the turbine immediately;

25.3.3 Close the attemperating water valve, change the auto control of feed water to manual

control and control the water supply well, prevent the boiler from being overfed with and lack of

water; monitor and adjust the water level of the deaerator and condenser, as well as shaft seal

pressure.

25.3.4 In the process of fire extinction, pay attention to control no cooling of cylinder, strictly

prevent water hammer accident, closely monitor the differential expansion and temperature

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change of all metals.

25.3.5 For boiler fire extinction, if it is to maintain low power operation, it shall keep initial steam

pressure and temperature down rate not exceed the permitted value and fulfill the operations or

checks as specified in section 25.3.2~25.3.4.

25.3.6 In the process of treatment, closely monitor we various differential expansion, axial

displacement, temperature, vibration and sound, etc. of thrust bearing pad.

26. Treatment of Accidents & Abnormity of the Motor

26.1 Conditions of motor emergency shutdown (shut down first and then start the standby)

a) When there is a fatal accident requiring emergency shutdown of motor (including

electric shock and the mechanical injury).

b) The machine driven by the motor is damaged or motor fan dropped out.

c) The motor and its subsidiary electrical equipment smoke or catch fire.

d) The rotating speed of motor slows down sharply and the current rises or reaches 0

(including the abnormal voltage and mechanical failure).

e) The temperature of motor or bearing rises sharply to exceed the permitted value and

keeps on rising.

f) Much vibration above the rated value occurs or shock occurs inside and friction exists in

between the stator and rotor.

g) In the case of flood or Water accident or fire accident, etc. that endangers safe

operation of the motor.

26.2 In any case as follows, it is permitted to start the standby motor first and then stop the

faulted motor:

a) There is abnormal sound or insulation burnt odor during the operation.

b) The motor or the starting governing equipment sparkles and smokes from the inside.

c) The vibration reaches the permitted value and exceeds the standard value for a short

time.

d) When the temperature of core, bearing, bearing bush, enclosure and end cover, etc. is

high abnormally and no treatment takes effect.

e) The cable lead of motor overheats too seriously, or leaks oil and blisters.

f) The cooler of the large-size sealed cooling motor gets fault.

g) The motor current rises to exceed the rated value or the imbalance value of three-phase

current exceeds more than 10% cannot recover.

h) The electric brush of DC motor catches fire seriously that cannot be extinguished in

operation

26.3 Treatment of Abnormal Operation & Accidents of Motor

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26.3.1 When there is any abnormal state occurring in operation of motor, it shall report to the unit

supervisor at once to assign special person to check.

26.3.2 For the tripped important motor (the one that will affect the output and safe operation of the

unit ), when there is no standby one or the standby one cannot be started quickly, in order to

keep the unit keep on operating, once forced closing of the tripped motor is permitted. But the

following cases are not included:

a. In case of fatal accident that requires immediate shutdown.

b. The equipment driven by the motor is broken.

c. The motor with protection operating to trip (for feed water pump & water circulating pump)

26.3.3 Treatment of motor tripping

a. Start the standby power.

b. If there is no standby power, it shall assign person to check, if no problem, restart it, if it

trips again, then prohibit starting and advise the maintaining personnel to treat.

26.3.4 Treatment of motor starting with sound but without rotating or abnormal rotating speed

a. Cut off the power supply of motor immediately and check it according to the cases above;

if the fuse has blown, replace with a new one, if the voltage is too low, there is the means to

adjust the voltage.

b. Advise the maintenance personnel to treat.

26.3.5 Treatment of motor rotor with current oscillating periodically in operation

a. Start the standby motor unit and stop the equipment with fault

b. It shall intensify monitoring of the equipment with fault if there is no standby one, and it

shall stop the unit with fault and report to the maintenance personnel if the check and

treatment fail and oscillating amplitude of ammeter increases.

26.3.6 Treatment of motor with smoking & fire and burnt odor

a. Switch off the power supply of the motor at once.

b. Extinguish the fire with the forceful dry powder extinguisher, 1211 extinguisher, CO2

extinguisher or the mist-sprinkling extinguisher. It is strictly prohibited to use high flow water,

sand and foam extinguisher to extinguish the fire.

c. After fire extinction, cut off the power supply of the faulted motor with and isolate it for

safety purpose, and advise the maintenance personnel to treat.

26.3.7 Treatment of motor with much vibration

a. Start the standby equipment and stop the operation of the equipment with vibration.

b. If there is no standby equipment, it shall lower the load of motor to see if the vibration can

decrease or disappear.

c. If the vibration continues, it shall cut off the power supply for treatment.

26.3.8 If the motor temperature in operation rises abnormally to exceed the permitted value, it

shall make the following checks:

a. If the voltage is lower than the specified value and the current is higher than the rated

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value.

b. If the cooling system and fan operate normally.

c. If the three-phase current (voltage) is in balance.

d. If the equipment drive is jammed and caused overload.

26.3.9 Check and treatment of motor with bearing temperature rising in operation

a. Check if the oil ring can rotate, if oil carriage is normal, if oil pipeline is blocked or oil

interrupted.

b. If oil quantity is sufficient, pressure and temperature are normal.

c. If the rolling bearing is overfed with or lacks oil.

d. If the cooling water of bearing is normal.

e. If there is abnormal sound or worn parts of the bearing.

26.3.10 Precautions for treatment of abnormal operation & accident of motor

a. When auxiliary power disappears, do not switch off the motor within 1 minute (except that

with low voltage trip).

b. In the case of tripping for low voltage protection operating, it is strictly prohibited to start

the motor forcedly.

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PART 6 Auxiliary Equipment & Common Service System

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Chapter 1 General Operation Rules of Auxiliary Equipment

1.1 Precautions for auxiliary equipment start-up

1.1.1 The auxiliary equipment after servicing must go through various interlocking and protection

tests and be qualified through test prior to trial run, and must be qualified through trial run prior to

operation.

1.1.2 Auxiliary equipment can only be powered on after the conditions are met through check

locally.

1.1.3 Before starting the 6,600V and principal 6,600V equipment, it shall assign special person to

check locally and starting conditions shall be met. The staff on duty shall stand by the emergency

button and stop it in time once discovering any problem.

1.1.4 After the outlet valve of the centrifugal pump is closed, can it be started (except the standby

pump) after the scoop tube opening is placed on “0”, forbidden to start with load;

1.1.5 After the motor is closed, it shall monitor tightly the returning time of current, forbidden to

start other equipment until the current returns;

1.1.6 Immediately reset the switch if trips after closing, and do not start any more until finding out

the cause;

1.1.7 It must not start more than two auxiliary equipment above 6.6 kv on one busbar at the same

time.

1.2 Check before auxiliary equipment startup

1.2.1 The local check and maintenance have been finished, work sheets have been called back,

equipment and surrounding impurities have been cleaned up, equipment’s appearance is

unbroken, connection is firm, safety cover of turning parts are installed, related meters have been

put into operation and illumination is sufficient.

1.2.2 The lubricating oil, quality, level and temperature of all oil sites are satisfactory, auxiliary

equipment temperature and motor temperature are satisfactory and cooling water is normal.

1.2.3 Motor is earthed reliably, if the motor has been serviced, its rotating direction shall be right

through test prior to connecting with auxiliary equipment, the insulation of motor which has

stopped for more than 3 days or possibly be affected with damp shall be tested for qualification.

1.2.4 Manual turning is flexible without any jamming, and the rotor does not reverse prior to start-

up.

1.3 Check after auxiliary equipment start-up

1.3.1 In normal condition, the motor’s long-time operating temperature shall be as specified on

the nameplate of the manufactory, refer to the following table for the temperature of each part if

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there is no regulation from the manufactory.

Permitted Temperature Rise of Different Insulation Grades

Insulation

GradeA E B F

Max Max p Max Max

Permitted

temp.

Permitted

temp. rise

Permitted

temp.

Permitted

temp. rise

Permitted

temp.

Permitted

temp. rise

Permitte

d temp.

Permitted

temp. rise

Stator and

rotor

winding

95℃ 55℃ 105℃ 65℃ 110℃ 70℃ 125℃ 85℃

Stator core 100℃ 60℃ 115℃ 75℃ 140℃ 80℃ 140℃ 100℃

Sliding ring 100℃ 60℃ 110℃ 70℃ 140℃ 80℃ 130℃ 90℃

Sliding

bearing80℃ 40℃ 80℃ 40℃ 80℃ 40℃ 80℃ 40℃

Rolling

bearing100℃ 60℃ 100℃ 60℃ 100℃ 60℃ 100℃ 60℃

The temperature of bearing in normal operation shall be stable, generally the sliding bearing

temperature shall not exceed 65℃ and the rolling bearing temperature shall not exceed 80℃.

The enclosure temperature of the motor with grade A insulation must not exceed 75℃;

The enclosure temperature of the motor with grade E insulation must not exceed 80℃;

The enclosure temperature of the motor with grade b insulation must not exceed 85℃;

If excess, it shall lower the output or take measures to lower the temperature.

1.3.2 Vibration shall accord with specification:

Rated rotating speed (r/min) 750 1000 1500 above 1500

Vibration value (mm) 0.12 0.1 0.085 0.05

1.3.3 The axial movement must not more than 2~4mm.

1.3.4 The current and temperature rise of motor shall accord with the specification.

1.3.5 The oil level of all lubricating oil tanks is normal without oil leak.

1.3.6 Good seal of the sealing parts of equipment.

1.3.7 There is no abnormal sound and friction sound of the turning equipment and motor.

1.3.8 The mechanical connection of all adjustment devices shall be in tact without dropping.

1.3.9 The pressure of the outlet and inlet, and flow of equipment conveying medium are normal.

1.3.10 There is water, gas, power and oil leak in the auxiliary equipment and the system to which

it is subordinate.

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1.4 Ceasing of rotating equipment

1.4.1 If there is reversal after the equipment stops, separate it immediately, find out and eliminate

the cause.

1.4.2 It shall be in standby state after the equipment stops, it shall keep the cooling water smooth,

if considering saving water, it can turn down the cooling water valve, but keep a record.

1.4.3 The rotating equipment is divided into “Run”, “Standby” and “Service”, three states. Any

person must not break the standby into service without approval.

1.5 Conditions of emergency shutdown of rotating equipment:

1.5.1 In the case where the motor or driven equipment has such accident that emergency

shutdown can avoid personal injury.

1.5.2 The driven equipment by motor is damaged seriously and can not keep on running;

1.5.3 In case of fire accident that endangers the equipment and personal safety;

1.5.4 IN case of serious leak of water and oil;

1.5.5 Bearing oil interrupts, smokes or temperature exceeds the specified value;

1.5.6 After closing, the motor fails in running or running at a lower speed than normal speed and

accompanied with abnormal noise;

1.5.7 After starting, the motor current does not return within specified time or there is no

indication of current;

1.5.8 After closing, the motor smokes or sparkles.

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Chapter 2 Industrial Water System

2.1 General

Industrial water pump house holds 3 industrial water pumps, 1 is vacuum pump and 2 water

filtering pumps. In normal condition, 1 or 2 industrial water pumps operate and others for standby;

for number of operating sets may be determined according to variation of season and water

consumption in the precondition of guaranteeing header pressure. There are interlocking devices

in between #1~3 industrial water pumps, if operating pump trips, the standby pump will start

automatically. One industrial pump house contains 2 blowdown pumps, which can realize

automatic start-up and shutdown in case foul water level is high.

2.2 Equipment specification

Equipment specification Industrial water pump

Water pump

specification

Model SX400-650

Flow m3/h 2,066

Head m 50

Speed r/min 980

Manufactory

Motor specification

Model YKK450-6

Power KW 400

Voltage V 6,600

Current A 47.4

Speed r/min 990

Manufactory

2.3 Inspection prior to start-up

2.3.1 Inspection work is finished, no foreign matters blocking operation, check if motor connection

and ground connection are sound, and insulation is qualified.

2.3.2 Oil level of all bearings is normal and oil quality is good, rotor shall be normal in turning;

2.3.3 Inlet valve of water pump is opened, and outlet valve is closed (if in standby, outlet valve is

opened, and water pump shall not inverse)

2.3.4 Water level of clarified water pond is normal, and the pond inlet valve is opened;

2.3.5 Various interlocks and protections of water pump are good through static test, and motor is

powered on.

2.3.6 Start water chamber vacuum pump to vacuumize the industrial water pump pipe.

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2.4 Start-up and operation

2.4.1 As receiving command or it is necessary to start pump, release the interlocking switch of

this pump, close operating switch and open outlet valve after water pump being normal in

operation.

2.4.2 Switch the interlocking switch of standby water pump on “Interlock” position;

2.4.3 Attention shall be paid to checking water level variation in clarified water pond to prevent

water shortage and overflow.

2.4.4 Shutdown the water chamber vacuum pump after industrial water pump is normal in

operation through checking.

2.3 Shutdown of water pump

2.3.1 As receiving pump shutdown command or it is necessary to shutdown water pump, open

the console switch, then water pump stops, check pump that shall not inverse, otherwise close

the outlet valve for treatment;

2.3.2 Put the water pump into “standby” state;

2.3.3 Check water level in clarified water pond;

2.3.4 Keep record.

2.6 Treatment of abnormal operation and accidents

2.6.1 In any case as follows, it is necessary to shut down the water pump for emergency:

a. Much vibration occurs in pump set and frication sound can be heard clearly inside pump

b. Motor has smoke belching and catches fire;

c. When bearing temperature exceeds the rated value or has smoke belching;

e. Water pump gland packing spray much water or has much smoke belching, which endangers

safety operation;

f. Industrial water pond lacks water, and water pump outlet pressure and current drop greatly;

g. Water pump or outlet pipe sprays water, which endangers personal safety.

2.6.2 Procedure of water pump emergency shutdown:

a. Pull down the console switch or emergency button of faulted pump immediately, then pump

shall shut down, and close the console switch after standby interlocks.

b. Release the interlocking switch of faulted pump, and the operating pump shall be normal

through checking;

c. Report to the unit supervisor, and contact for removing the fault, put it into standby after

removing fault, and keep record.

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Chapter 3 Oil Purification System of Steam Turbine

3.1 Introduction of equipment

The GJZ-6 coalescing & isolating oil purification system can remove free water and solid pollutant

in steam turbine oil with high efficiency, and also can give bypass or on-line purification to oil

independently according to requirement. It comprises circulating filtering system, coalescing

system, isolating system, water discharge system, oil discharge system and safety protection

system, etc., and the main operating principle is: the steam turbine oil is pumped into circulating

filter that has a 6 micron filter element, which can meet the requirement of oil cleanliness in

common condition. When it is necessary to separate water content, steam turbine oil will flows

into the coalescing filter element in coalescing and isolating vessel via protective filter, because

the unique effect of polar molecule in coalescing filter element material, free water and emulsified

water in oil will form larger water drop after flowing through filter element, and will settle to the

vessel bottom with gravity action, and globule of small size will enter the isolating filter element

together with steam turbine oil under effect of inertia, since this element is made of special

hydrophobic material, when oil flow through filter element, globule will be blocked out from filter

element, and oil will flow through the filter element to be discharged from outlet, the globule

blocked out of filter element, with mutual condensing, the size will be larger and larger and settle

to water storage tank at vessel bottom with gravity action to be discharged.

3.1 Start-up of oil purification device

3.2.1 Contact with electric and thermodynamic personnel and powering on of related equipment

and signal are good through test;

3.2.2 Check if valve position of oil purification device is correct;

3.2.3 Turn START/STOP knob to right to start oil pump operation;

3.2.4 Open the outlet water valve of auto drainer, water discharge shall be normal, and discharge

level meter indicates that water level varies stably.

3.2.5 Oil purifier can operate continuously in steam turbine operating or shutdown state.

3.2.6 After oil purification system starts to operate, check oil level in main oil tank frequently for

normal.

3.3 Shutdown of oil purification device

3.3.1 Close the outlet water valve of auto drainer;

3.3.2 Turn START/STOP knob to left to stop oil pump operation;

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3.3.3 Close inlet valve and outlet valve of oil purification device;

3.3.4 Turn the power switch to OFF position.

3.4 Safety protection

3.4.1 Motor overload protection: in case of motor short circuit or overload, auto air switch will

break to stop the device, meanwhile the entire six alarm indicator lamps will flash from left to

right, and top alarm lamp will flash.

3.4.2 Power source open-phase and fault-phase protection: in case of incorrect phase sequence

or open-phase in three-phase power, the six red alarm indicator lamps and yellow alarm lamp will

flash synchronously.

3.4.3 Monitoring and negative protection of inlet vacuum degree: in equipment operation, if

pressure of inlet piping is lower than set value (-0.8 Bar), inlet vacuum switch will operate to stop

equipment, and then outlet pressure alarm lamp (LP01) and top alarm lamp (LP10) will flash

synchronously.

3.4.4 Differential pressure alarm of protection filter: in operation, if differential of protection filter is

up to 2.4Bar, protection filter differential pressure switch (PS02) will operate, and differential

pressure alarm indicator lamp of filter (LP02) will flash successively, then auto shutdown will

make after 2h. And during this 2h, if differential pressure becomes less than 2.4Bar, alarm signal

will trip automatically.

3.4.5 Differential pressure alarm of circulating filter: During equipment operation, if differential

pressure of circulating filter is up to 2.4Bar, differential pressure switch (PS04) of circulating filter

will operate, and differential pressure alarm indicator lamp of circulating filter (LP04) will flash

continuously, then auto shutdown will make after 2h. And during this 2h, if differential pressure

becomes less than 2.4Bar, alarm signal will remove automatically.

3.4.6 Differential pressure alarm of coalescing and isolating vessel: In system operation, if

differential pressure of vessel inlet and outlet is up to 3.0Bar, differential pressure switch (PS03)

of dehydrator filter will operate, and differential pressure alarm indicator lamp of circulating filter

(LP03) will flash successively, then auto shutdown will make after 2h. And during this 2h, if

differential pressure becomes less than 3.0Bar, alarm signal will trip automatically.

3.4.7 High water level control and alarm: as water level in water storage tank is up to the set high

water level, water discharge valve of equipment will open, and meanwhile water discharge

indicator lamp on control panel will light. Generally, water level will be below the high water level

position within 1~2S after water discharge valve opening. In case of water discharge pipe

blocking, water level will maintain on high water level for 20S, after which high water alarm

indicator lamp (LP08) will flash for 5min, and then equipment will shut down.

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3.4.8 Low water level control and alarm: After opening water discharge valve, water level will

decrease promptly, as decreasing to the set water level, water discharge valve will close, water

level will no longer decrease thereupon. In case water level keeps on decreasing to the set ultra

low level, equipment will shut down, meanwhile low level alarm lamp (LP07) will flash.

3.4.9 Alarm of water discharge time being over long: if water level is lower than the high water

level as a result of water discharge valve opening, and if the discharge time is over long that

exceeds 5min, the water discharge valve can not close, equipment will shut down, and

meanwhile alarm lamps of low water level and high water level will flash synchronously.

3.5 Daily operation and maintenance of oil purification device

3.5.1 Daily operation and maintenance of oil purification device:

a. Perform alarm indicator lamp test in the day shift of every Monday, press the alarm lamp test

button, then all the alarm buttons will light, thus it can check if the alarm lamp works normally;

b. After fault is removed every time, alarm reset button shall be pressed down for tripping alarm

state, and then equipment can be re-started;

c. Pay attention to the checking of main oil tank oil level to prevent oil leak as a result of water

discharge valve fault;

d. Check if the motor operation is normal;

e. Attention shall be paid that parameters of inlet vacuum degree, system operating pressure,

vessel inlet pressure, vessel outlet pressure and operating oil temperature shall be checked in

the specified range;

f. In case of filter element replacement, equipment operation shall be stopped, and attention shall

be paid to the electric pollution, which shall be prevented in replacement process.

3.5.2 Operating procedure of coalescing and isolating filter element replacement:

a. Stop the operation of oil purification device;

b. Close the inlet ball valve;

c. Open the ball valve and vent valve at the underpart of water storage tank;

d. Open the inlet and outlet ball valve of coalescing and isolating vessel;

e. Open the vent valve on coalescing and isolating vessel top;

f. Open oil pump to discharge the oil in coalescing and isolating vessel thoroughly, and after

confirming no oil being in system, stop the oil pump.

3.5.3 Operating procedure of filter elements replacement in protection filter and recirculating filter:

The operating procedure of filter elements replacement in protection filter and recirculating filter

are basically identical with that of the coalescing and isolating filter element replacement, in

addition, in filter element replacement, sampling valve of filter elements in protection filter and

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recirculating filter can be used to discharge oil in filter element.

3.6 Abnormal operation of oil purification device and its treatment

3.6.1 Frequent fault of oil purification device mainly includes the following:

a. Auto water discharge valve operates disorderly resulting in oil spills from discharge outlet or no

water discharging.

b. Oil water interface instrument is out of order;

c. Blocking occurs in inlet filter element, circulating filter, and coalescing and isolating filter

element;

d. Oil pump operates abnormally, and has abnormal sound or vibration.

3.6.2 The above fault shall be treated after stopping oil purification device.

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Chapter 4 Lubricating Oil System of Steam Turbine

4.1 Inspection prior to lubricating system start-up.

4.1.1 Check if the position of lubricating system valves is correct;

4.1.2 Affirm the emergency oil release valve of main oil tank is closed.

4.1.3 Affirm the oil release valve of main oil tank is closed.

4.1.4 Oil level of main oil tank is normal and oil quality is qualified;

4.1.5 Oil temperature of main oil tank shall be kept higher than 25ºC prior to unit start-up and

38~42ºC in steam turbine normal operation. Electric heater can be put into operation when oil

temperature is low and stopped when oil temperature is up to 40ºC.

4.1.6 Make sure inlet and outlet valves of oil cooler are closed;

4.1.7 Make sure inlet baffle of smoke exhaust fan is closed;

4.1.8 All the motors are in good insulation;

4.1.9 No leak phenomenon in oil piping;

4.1.10 All oil pumps are on “Manual” position;

4.1.11 Pressure of gas tank is normal.

4.2 Start-up of lubricating system

4.2.1 Start a smoke exhaust fan of main oil tank, adjust the inlet baffle of smoke exhaust fan,

create the vacuum of main oil tank larger than 0.5KPa, and put the other smoke exhaust fan on

“Auto” position;

4.2.2 Start the AC lubricating oil pump, check if the outlet oil pressure is within 0.09~0.15MPa;

4.2.3 Put the DC lubricating oil pump on “Auto” position, and check the forced link circuit of DC oil

pump.

4.2.4 Check over the system, which shall be of no leak;

4.2.5 Open the inlet valves of one jacking oil pump, and after affirming that inlet oil pressure of

jacking oil pump being higher than 0.039MPa, which meets the starting condition of jacking oil

pump, start one jacking oil pump, and check if the jacking oil pressure is about 10~12Mpa, if the

oil pressure is much lower, it may start two jacking oil pumps, if the oil pressure is still too low, it

shall find out the cause;

4.2.6 Check the jacking oil pressure shall be higher than 6.0MPa, and diameter of bearing shall

be jacked up 0.05～0.08mm.

4.2.7 Check if the oil return of every bearing is normal

4.2.8 Start the turning gear to check if the rotor rotates at a speed of 7~8r/min;

4.2.9 Check if the turning gear current and internal sound is normal, listen to if there is any

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metallic friction sound inside steam turbine. And stop one jacking oil pump.

4.2.10 Measure the eccentricity of shaft that shall be < 0.076mm and less than the original value

by 0.03mm.

4.3 Stop of lubricating system

4.3.1 Stop the steam turbine turning gear, and rotor will stop rotating thereupon;

4.3.2 Trip auto, and stop operation of jacking oil pump;

4.3.3 Trip the “auto” mode of DC lubricating oil pump;

4.3.4 Stop the AC lubricating oil pump;

4.3.5 Trip the “auto” position of standby smoke exhaust fan of main oil tank, and stop the smoke

exhaust fan.

4.3.6 Put electric heater of main oil tank on “stop” position.

4.4 Put-in and shutdown of oil cooler

4.4.1 Precautions for oil cooler put-in and shutdown:

4.4.1.1 Prior to operation, it shall check if oil system operates normally, and oil temperature and

pressure are within normal range;

4.4.1.2 In start-up or shutdown operation, attention shall be paid to the variation of oil

temperature & pressure, which shall be kept steady. Prior to oil cooler put-in, air in oil piping shall

be drained away.

4.4.1.3 Pay attention to the oil level of main oil tank, and contact for making oil up to normal if

necessary;

4.4.1.4 There shall be no oil leak in oil cooler;

4.4.2 Oil cooler put-in

4.4.2.1 Check if the oil outlet valve of oil cooler is closed, open oil inlet valve slightly, close air

exhaust valve after draining away air, then open the oil inlet valve wide (in case of put-in after

overhaul, the above operation shall be performed after accumulated water being drained away);

4.4.2.2 Open water discharge valve at water side, and check if there is any oil leakage, if any, it is

strictly prohibit to put in. close water discharge valve after leakage check over.

4.4.2.3 Slowly open the water inlet valve, and close air exhaust valve at water side after draining

away air, then open the water outlet valve;

4.4.2.4 Open the oil outlet valve of oil cooler;

4.4.2.5 Regulate oil temperature within specified range. In oil temperature regulation in operation,

it shall open the water inlet valve wide and regulate oil temperature with return water valve, thus

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prevent fullness of oil cooler water side from being little, and deposit corrosion from accelerating.

4.4.3 Oil cooler shutdown

4.4.3.1 Check if the oil outlet valve of oil cooler has been closed;

4.4.3.2 Close cooling water outlet valve of oil cooler;

4.4.3.3 If servicing is necessary, the oil inlet valve and water inlet valve of oil cooler shall be

closed, and maintenance personnel shall be contacted to discharge the accumulated oil & water

in this oil cooler thoroughly;

4.4.3.4 Standby mode of standby oil cooler

For standby oil cooler, oil inlet valve & water inlet valve shall be opened and oil outlet valve and

outlet valve shall be closed to guarantee oil cooler in oil-filled and water-filled state for standby

and prevent water side from scaling, and oil side from water or air entering.

4.5 Inspection and maintenance in lubricating oil system operation

4.5.1 Check if operation of all the oil pumps and smoke exhaust fans are normal, and vibration

and motor current within specified range.

4.5.2 Check if bearing lubricating oil pressure is within the range of 0.09~0.15MPa, and jacking oil

pressure is normal in turning state.

4.5.3 Check outlet oil temperature of oil cooler for normal, lubricating oil temperature shall be

higher than 25ºC in turning; as steam turbine being in normal operation, lubricating oil

temperature shall be within a rang of 38~42ºC, and oil pressure of oil cooler shall be larger than

water pressure.

4.5.4 Normally, bearing return oil temperature is below 65ºC, metal temperature of journal bearing

#1~3 is below 107ºC, metal temperature of journal bearing #4~5 is below 75ºC, and metal

temperature of thrust bearing is below 99ºC.

4.5.5 Monitor oil level of main oil tank for normal, if it is over high or too low, it may discharge or

make up oil to oil reservoir.

4.5.6 Oil pressure of jacking oil pump inlet shall be >0.039MPa.

4.5.7 Pay attention to the lubricating oil quality, clean or filter oil if necessary, and enhance

chemical supervision to steam turbine oil.

4.5.8 When turbine operates in rated speed, oil pressure of main oil pump inlet and outlet shall be

normal.

4.5.9 Check if no leak in system.

4.5.10 Starting oil pump, AC &DC lubricating oil pumps, jacking oil pump and smoke exhaust fan

shall be tested periodically according to requirement.

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4.5.11 Remarks

4.5.11.1 When unit starts and stop, the main oil pump operating at above 2,700r/min ( 90% rated

Rev) can meet all the oil demand of speed governing and lubrication;

4.5.11.2 The capacity of single oil cooler is 100%, and only one set is enough in normal

operation;

4.5.11.3 The brand of lubricating oil is 32# steam turbine oil with cleanness up to grade NAS7.

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Chapter 5 Circulating Water System

5.1 Check & put-in before circulating water system start-up

5.1.1 Make sure the interlock protection of circulating water system is qualified through test and

has been put into operation;

5.1.2 Make sure the circulating water pump is qualified in insulation and has been powered on,

the circulating water inlet & outlet motor-operated disc valves on side A and B of condenser and

outlet disc valve of circulating water pump have been powered on, and the outlet disc valve of

circulating water pump is on “Auto” position;

5.1.3 Check if the position of the circulating water system valves is right:

a. Put the bearing cooling water of circulating water pump into operation;

b. Close all the water-discharging valves of circulating water system;

c. Make sure that the water level of the cooling water tower and suction bay at inlet of circulating

water pump is normal;

e. Fill the pump with water;

f. Open the circulating water outlet and inlet valves on side A of condenser and the inlet valves on

side B.

g. Close the manual valve and bypass valve of circulating water to the two strainers of generator

air cooler and turbine oil cooler. That is to stop all circulating cooling water supplied to generator

air cooler and turbine oil cooler. Prevent water hammer due to insufficient exhaust as the

circulating water pump starts;

h. If the condenser has been discharged of water, it shall fill the condenser and inlet circulating

water pipeline with industrial water, when water can be seen in the cooling water tower, stop

filling and return to makeup water mode of industrial water pool.

5.1.4 Contact the local checker to open the outlet disc valve of circulating water pump to the

extent of15%, then it shall interlock start the circulating water pump, pay attention to the motor

current and outlet pressure which indication shall be normal, monitor the inner noise and

vibration of the pump set and check if the bearing temperature is < 70℃;

5.1.5 Pay attention to that the operating time when the pump’s outlet valve is not opened or the

pump fails in draining water to the system must not exceed 60s;

5.1.6 If one circulating water pump accords with the standby condition, put it on “AUTO” position

and put the outlet disc valve into “AUTO”;

5.1.7 After the cooling water flowing into the condenser becoming normal, check if the generator

air cooler, outlet and bypass valves are all opened, open slowly the strainer inlet valve of

circulating water to generator air cooler to fill the generator air cooler with water;

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5.1.8 Open slowly the strainer inlet valve of circulating water to the generator air cooler manually,

fill the cooling water pipeline of turbine oil cooler slowly with water, and thereafter put it into

operation.

5.2 Normal shutdown of circulating water system

5.2.1 When the exhaust temperature of LP cylinder is lower than 50 and circulating water has℃

no user, it can contact the relative staff to stop the running of the circulating water pump;

5.2.2 Check if the circulating pump and outlet disc valve are on the “auto” position, assign special

staff to monitor locally before pump shutdown;

5.2.3 Contact the local staff to close the outlet disc valve of circulating water pump, when closing

to the extent of 75%, it shall interlock stop the circulating pump and check that the pump should

not reverse.

5.3 Normal switching of circulating water pump

5.3.1 Circulating water system is normal, standby pump is good and has the starting conditions

as checked in an all round way;

5.3.2 Make sure the outlet disc valve of standby pump closed;

5.3.3 Check if the standby circulating pump and outlet disc valve are on “Auto” position;

5.3.5 When opening the outlet disc valve of circulating pump to the extent of 15％, the standby

circulating pump will interlock start;

5.3.6 Check if the outlet pressure, vibration, sound and motor current of standby pump are

normal;

5.3.7 After everything is normal through check, close the outlet disc valve of original running

pump, ensure the interlock stopping the original pump, pay attention to the normal pressure of

circulating water header and avoid the inverse flow of stopped pump;

5.3.8 When the original running pump is used as standby, put the original running pump and

outlet disc on “Auto” position.

5.4 Half side cleaning of condenser

5.4.1 Half side of condenser is stopped for servicing:

5.4.1.1 Contact the unit supervisor, prepare for half side cleaning or leak stoppage of condenser,

check thoroughly the circulating water system and record the condenser vacuum and exhaust

temperature indication;

5.4.1.2 Contact the unit supervisor to lower the unit load to 70% or so;

5.4.1.3 Check that the back pressure of condenser shall not be lower than 16.9 Kpa, the exhaust

temperature must not exceed 80 ,℃ otherwise put the rear cylinder spray into operation to reduce

the temperature or lower the load;

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5.4.1.4 Close slowly the air valve of condenser on stopped side and circulating water inlet motor-

operated disc valve, pay attention to that the back pressure of condenser shall not be lower than

16.9Kpa, start another vacuum pump if necessary to intensify monitoring of the vibration,

differential expansion and axial displacement;

5.4.1.5 Close the circulating water inlet and outlet motor-operateddisc valve of condenser on the

stopped side, open the circulating water discharge valve on the stopped side, pay attention to the

change in vacuum. If there is serious leakage in the condenser’s pipe, here pay attention to

vacuum decreasing, it shall close the circulating water discharge valve immediately, report to the

unit supervisor to restore the original running mode immediately and make decisions after

reporting;

5.4.1.6 After circulating water on the stopped side drain away, the vacuum shall keep within the

permitted range, power off the motor-operated inlet disc valve of condenser on the stopped side,

motor-operated outlet disc valve and rubber ball pump motor, then it may permit the maintenance

personnel to open the manhole to work;

5.4.1.7 In the whole process of cleaning and leak stoppage, it shall monitor strictly the change in

the condenser vacuum and exhaust temperature, if any abnormality and vacuum decreases

sharply, stop working immediately and load on as per vacuum.

5.4.2 Half side operation of condenser:

5.4.2.1 Work sheets of the cleaning and leak stoppage of condenser has been packed up, all the

safety measures have been removed;

5.4.2.2 Check that the manhole valve is closed tightly, close water outlet of put-in side, power on

the motor-operated inlet disc valve of condenser on the put-in side, motor-operated outlet disc

valve and rubber ball pump motor after confirming they are qualified in insulation;

5.4.2.3 Open narrowly the outlet motor-operated disc on the stopped side of condenser manually

to charge water on water side, open the outlet and inlet motor-operated disc valve of circulating

water wide; and open the air valve of condenser on the put-in side.

5.4.2.4 If the other side requires cleaning or leak stoppage, then after the put-in side operating

becomes normal, stop the other side according to the above methods;

5.4.2.5 After both sides of condenser become normal, stop one vacuum pump if there are two

pumping operating, and the other back to standby;

5.4.2.6 Report to the unit supervisor after checking thoroughly that the exhaust temperature and

vacuum of the unit are normal, the leak stoppage work is finished, the unit load returns to normal

and stop the LP cylinder spray.

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5.5 Washing of condenser rubber ball

5.5.1 Hand-operated put-in:

5.5.1.1 Before putting the rubber-ball system into operation, the operator shall contact with the

personnel of Centralized Control Room to make good preparation for operation;

5.5.1.2 Check that there is no need of maintenance and the equipment is in good condition, the

meters are all presented and the spot is clean;

5.5.1.3 Turn the rubber ball pump shaft to run flexibly and without jamming. Confirm the motor

insulation is good and power on;

5.5.1.4 Check that the inlet valve of rubber-ball pump on the washing side has closed and the

water discharge valve of Loaded Ball Room has opened, and the outlet valve has closed too, and

the switch valve of Loaded Ball Room has been turned to the position of collecting the balls;

5.5.1.5 Open the top cover of Loaded Ball Room, and close it and water discharge valve after

putting into adequate rubber-ball (500 pieces);

5.5.1.6 Open the inlet valve of rubber-ball pump slightly and fill Loaded Ball Room with water.

When there is water overflowing, close the air valve and open the inlet valve of rubber-ball pump

wide;

5.5.1.7 Contact with the personnel of Centralized Control Room to put the rubber ball of

Condenser into washing. Keep records of the vacuum, load, exhaust temperature, circulating

water pressure and circulating water outlet and inlet temperature;

5.5.1.8 Start the rubber-ball pump. Open the outlet valve of Loaded Ball Room and switch the

valve to the Wash position to put it into operation. Pay attention to observing the vacuum change

of condenser.

5.5.2 Collecting ball and shutdown

5.5.2.1 The rubber-ball shall be fetched and the switch valve shall point at the position of Wash

before the process of washing is completed;

5.5.2.2 Close the outlet of Loaded Ball Room to shut down the operation of rubber-ball pump and

close the inlet valve of pump;

5.5.2.3 Open the air release valve and water discharge valve of Loaded Ball Room and open the

top cover to pull out the rubber-balls;

5.5.2.4 Figure out the percentage of fetching rubber-ball and compare the washing effect after

finishing washing (the percentage of outballs/inballs).

5.5.3 Program control

5.5.3.1 The method of check, ball filling the and air release of Loaded Ball Room is the same with

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the hand- operated process;

5.5.3.2 Check that the rubber ball washing equipment is in the state of “program control”, press

the button “Program/ON” to check if all motor-operated valves and rubber-ball pumps operating

normally;

5.5.3.3 The washing is to end 30 minutes later and the system automatically starts to fetch the

balls ball fetching is to end after another 20 minutes with all motor-operated valves closed and

rubber ball pump shut down.

5.6 Inspection & maintenance in operation

5.6.1 Reinforce the inspection and maintenance of circulating water system in operation, pay

attention to the variation of steam condenser vacuum.

5.6.2 Control the circulating water inlet temperature not to exceed the specified value;

5.6.3 Check if the valves of circulating water system are sound without leak, and water outlet

temperature difference between steam condenser two sides are not more than 2ºC;

5.6.4 Monitor the water outlet differential pressure between two sides of condenser is normal;

5.6.5 Monitor and check if the open & close positions of steam condenser inlet & outlet motor-

operated disc valves are correct;

5.6.6 Monitor inlet strainer of circulating water pump that shall not be blocked; otherwise,

maintenance personnel shall be informed for clearing;

5.6.7 Pay attention to checking bearing oil level, bearing temperature, and motor coil temperature

that shall be within the specified range, otherwise, give treatment in time;

5.6.8 Washing time of rubber-ball is from 60 to 80 minutes every time. From March to June, the

time for putting the balls is on Monday, Wednesday, and Friday every week. At the other time, the

time is on Tuesday and Friday. If discovering any dirt in the copper pipeline of Condenser, it may

increase the number of times of rubber ball washing. After finishing washing, it shall switch the

electric push rod into the position of “ON” in order to avoid jamming of circulating water.

5.7 Abnormal operation of circulating water system

5.7.1 Phenomenon:

5.7.1.1 Vacuum degree of steam condenser decreases sharply, and steam exhaust temperature

of LP cylinder rises sharply;

5.7.1.2 Circulating water inlet pressure decreases or to zero;

5.7.1.3 Water outlet temperature of air cooler, outlet oil temperature of oil cooler and temperature

of all bearings rise sharply.

5.7.2 Treatment

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5.7.2.1 Once circulating water interruption is ascertained, unit load shall be decreased to zero

immediately, inlet & outlet disc valves of steam condenser or outlet valve of circulating water

pump shall be checked for mis-close, if any, it shall be opened at once. The auxiliary water pump

shall be started for recovering water supply as soon as possible, if fails, shutdown shall be

performed promptly;

5.7.2.2 After shutdown for fault, if water supply for steam condenser can not be recovered

temporarily, condensate pump recirculation valve shall be opened in time.

5.7.2.3 In case of circulating water interruption, the interconnection valve between industrial water

and circulating water shall be opened in time, and attention shall be paid to the metal temperature

of all the auxiliary equipment, outlet temperature of oil cooler and air cooler that must not exceed

the specified value;

5.7.2.4 In case of circulating water interruption, pay attention to if the steam condenser rupture

disk operates, if any, perform shutdown immediately.

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Chapter 6 Shaft Seal & Vacuum System of Steam Turbine

6.1 Specification of shaft seal system

6.1.1 Steam seal of the steam turbine is divided into HP steam seal, MP seal and LP seal. The

high & MP external steam seals and LP rear steam seal are equipped with steam seal casing and

steam seal ring, the latter is mounted in the former and pressed hard with spring leaf, the steam

seal casing is made up of two-half, the horizontal split is fixed with bolt and located with taper pin,

the bottom of lower half is located with flat key, and the shaft direction position is adjusted with

adjustable gasket. Steam seal rings of both HP and medium are stepped labyrinth structure, and

LP steam seal ring is plain structure. Steam seals of high and MP cylinder diaphragms are the

flush type, and are riveted into diaphragm with fillet. The steam seal ring of LP diaphragm steam

seal is mounted in septalium, and is pressed tightly with spring leaf.

6.1.2 The steam seal system is self-sealing system, in steam turbine start-up and with low load,

seal steam is supplied by auxiliary steam header; in high load condition, steam exhausted by high

and MP cylinders will escape into the steam seal casing, and will be discharged from steam

supply chamber to supply to LP steam seal, and excess seal steam will escape into steam

condenser via overflow control valve.

6.2 Start-up of shaft seal system

6.2.1 Check prior to shaft seal system start-up

6.2.1.1 Check if the position of shaft seal system valves is correct;

6.2.1.2 As the unit is in turning state, and steam seal supplies water to the steam inlet governing

valve, check if the drain valve is opened, no accumulated water inside pipe, and water stored in

inlet & outlet pipe of high & medium & low pressure steam seals has already been drained away;

6.2.1.3 Circulating water system is in normal operation, and steam condenser has water flowing

in.

6.2.1.4 Condensate system operates normally, and shaft seal heater has water flowing in.

6.2.1.5 Affirm multi-level U water seal is full of water, and priming valve is closed.

6.2.1.6 Affirm the drain system of shaft seal heater and steam condenser is opened;

6.2.17 Air source for overflow control valve, pressure and temperature reducing valve of LP

steam seal is supplied normally.

6.2.1.8 Check that HP steam supply temperature shall be of not very high difference with the rotor

metal surface temperature of high & MP steam turbine.

6.2 Shaft seal system put-in

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6.2.2.1 Open the motor-operated valve of overflow valve and auxiliary steam inlet governing

valve;

6.2.2.2 Regulate the pressure of seal steam supply header to that of governing valve setting

point;

6.2.2.3 Start a shaft seal heater blower, and the other for standby, regulate the water level of shaft

seal heater;

6.2.2.4 Close drain valves of steam seal return steam pipes of HP & MP cylinder, and close the

drain pipe of steam seal return steam header.

6.2.2.5 Regulate pressure of steam seal header to 0.02~0.03MPa, LP steam seal temperature to

121ºC~176ºC, and difference between rotor metal temperature of high & MP steam turbine shaft

seal and steam pressure of shaft seal to ≯111ºC;

6.2.2.6 Check if the continuous drain operation of steam seal header between steam

attemperating section and LP steam seal is normal.

6.2.2.7 Close drain valve on steam seal piping after steam supply of steam seal being normal;

6.2.2.8 Precaution:

① In cold start-up, it shall pump vacuum first, and then supply steam to steam seal;

② In warm-hot start-up, it shall supply steam to steam seal first, and then pump vacuum.

6.3 Start-up of vacuum system

6.3.1 Check prior to vacuum system start

6.3.1.1 Check if valve position of vacuum system is correct, and check over the system;

6.3.1.2 Ascertain air valve of steam condenser is opened;

6.3.1.4 Ascertain vacuum breaker valve of steam condenser is closed;

6.3.1.5 Check if the water level and temperature of vacuum pump air-water separator are normal;

6.3.1.6 Ascertain inlet valve of vacuum pump is on open position;

6.3.1.7 Ascertain steam condenser man hole is closed, and rupture disk of LP cylinder is

undamaged;

6.3.1.8 Ascertain condensate pump A & B and LP heater vacuum valve, the vacuum valves of LP

heater drain pump A & B are opened;

6.3.1.9 Ascertain steam condenser has circulating water inputted in, condensate pump is in

operation and steam seal supplied steam to the shaft seal.

6.3.2 Startup of vacuum pump:

6.3.2.1 Open the inlet of vacuum pump;

6.3.2.2 Start the vacuum pump and check IF vacuum pressure and current are normal;

6.3.2.3 Start inlet valve of another vacuum pump and place it on “AUTO” position.

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6.4 Shutdown of shaft seal and vacuum system

6.4.1 As steam turbine rotor idle runs to 2,500r/min, trip interlocking switch of standby vacuum

pump to stop vacuum pump operation;

6.4.2 As vacuum degree of steam condenser decreases to 0, stop shaft seal steam supplying and

shaft seal heater blower;

6.4.3 Close steam inlet governing valve of steam seal and the motor-operated valve on both

sides of overflow control valve.

6.5 Shaft seal system operation of steam turbine in abnormal cases

6.5.1 In case of load reduction, transfer the steam seal to auxiliary steam header for steam

supplying, in transferring, drain away the drainage in pipe, and pay attention to regulating steam

supplying temperature of steam seal to match with the metal surface temperature of HP & LP

rotor with the temperature difference ≯111ºC.

6.5.2 In case of steam turbine shutdown, seal steam shall be supplied by neighboring unit and

the temperature shall be guaranteed for matching so as to avoid mismatching between HP steam

temperature and cylinder end wall metal temperature as a result of prompt transfer of steam seal

steam supplying source.

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Chapter 7 Condensate System

7.1 Inspection prior to start-up

7.1.1 Check if the maintenance of condensate system is completed, the site is clean, and

equipment is sound;

7.1.2 Check if the positions of all the valves in condensate system are correct;

7.1.3 Contact thermodynamic personnel to power on all the meters, motor-operated valve and

protections, check if pointers are all complete and indicating correctly;

7.1.4 Condenser has circulating water supplied to the water side;

7.1.5 Check if the water level of steam condenser is normal. Check if the water make-up system

of condenser is normal;

7.1.6 Check if the oil level of condenser pump bearing is normal, and oil quality is qualified; the

bearing cooling water and packing sealing water are smooth; the rotor is flexible and unjammed

in turning;

7.1.7 Power on after confirming insulation of condensate pump motor is qualified;

7.1.8 Check if the condensate recirculating hand-operated valve is on open position, if outlet

valve of condensate pump is closed, if the condensate recirculating valve and the outlet motor-

operated valve of condensate pump are powered on, and if the outlet motor-operated valve of

condensate pump is on auto position.

7.2 Start-up of condensate pump

7.2.1 Make sure condensate pump inlet valve is full opened and outlet valve is closed, and the air

extraction valve is properly opened.

7.2.2 Press the button “Start-up” of condensate pump, pay attention to the current return time,

and if the on load current is normal;

7.2.3 Check and confirm interlocking start-up of outlet valve after starting condensate pump;

7.2.4 Adjust the condensate recirculation valve to maintain normal condensate pressure;

7.2.5 Adjust the bearing cooling water and gland sealing water of condensate pump to normal;

7.2.6 Check if the vibration and sound of condensate pump are normal;

7.2.7 As the other condensate pump is up to the standby condition, put it on “Auto” position.

7.3 Shutdown of condensate pump

7.3.1 In shutting down the condensate system operation, it is necessary to release the

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interlocking switch of auxiliary condensate pump first. Start the standby pump first in switching

condensate pumps.

7.3.2 Adjust the condensate recirculation valve to maintain the pressure of condensate water

within the normal range.

7.3.3 Close the outlet motor-operated valve of condensate pump, pay attention to the variation of

condensate header pressure and the water level of steam condenser and deaerator.

7.3.4 Shut down the condensate pump.

7.3.5 When the condensate pump acts as standby after shutdown, put it on the “auto” position

and open the outlet motor-operated valve.

Check the motor-operated outlet valve and pay attention to the pressure change of the

condensed water main pump and water level of the Condenser and deaerator;

7.4 Put-in and stop of LP heater

7.4.1 Startup of LP Heater along with the turbine

7.4.1.1 Before the turbine impulsing, LP Heater has been supplied with condensate, close the

water discharge valves of all LP Heaters that use emergency drain mode. Open the extraction

valve of LP heater #4, 5, 6 & 7, creation of vacuum of LP heater is in good condition, position of

all valves is right and instruments are sound;

7.4.1.2 After the turbine impulsing, open air inlet valves of all LP heaters and check if the water

level of all heaters is normal;

7.4.1.3 When the load rises to 45~67.5MW (1/3~1/2 of rated load), close the drain stop valve of

LP heater #4, 5 & 6 to condenser and start the LP heater drain pump.

7.4.2 Put-in of LP Heater after maintenance

7.4.2.1 Check to confirm that all valves of LP Heater and meters are in good condition prior to

start;

7.4.2.2 Close the water discharge valve on steam side and confirm to open the drain valves

before and after extraction check valve;

7.4.2.3 Check and confirm that the water discharge valve on the water side of LP heater in

operation is closed and the air valve is opened;

7.4.2.4 Open slowly the water inlet valve on the water side of the LP Heater in operation and

conduct water filling. When water appears at the water-side air valve, close the air valve,

gradually open the water outlet valve on the water side, and close the bypass valve of

condensate;

7.4.2.5 Open slowly the extraction valve of the LP Heater in operation and pay attention to the

vacuum change of condenser;

7.4.2.6 Open slightly the steam inlet valve of LP Heater in operation and increase the

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temperature at a rate of 2 /min ℃ that shall not exceed 3 /min℃ maximally;

7.4.2.7 Close the drain valves before and after corresponding extraction check valve;

7.4.2.8 Gradually open the steam inlet valve of LP Heater in operation according to the

temperature rise of LP heater in operation;

7.4.2.9 The drain water of LP Heater # 4 & 5 shall be dumped into the LP Heater #6, and it shall

start the drain pump according to the water level of #6m and check the automatic control

equipment in normal operation and adjusting water level normally.

7.4.3 Paralleling off of LP Heater

7.4.3.1 Close the steam inlet and the corresponding check valve of the LP heater paralleled off;

7.4.3.2 In paralleling off the LP Heater, it shall dump the drain water from last stage LP heater into

condenser, close the drain governing valve and hand-operated valve of this stage LP heater to

the next stage LP heater; in paralleling off the LP heater #6, it shall dump the drain water of LP

heater into the condenser and stop the LP heater drain pump;

7.4.3.3 Close the extraction valve of paralleled-off LP Heater and open the water discharge valve

on the steam side;

7.4.3.4 Open the condensate bypass valve of paralleled-off LP Heater and close the water outlet

and inlet valve and pay attention to the change of the pressure and temperature of deaerator and

the vacuum of condenser.

7.5 Startup and stop of LP Heater drain pump

7.5.1 Check and operation of LP Heater drain pump

7.5.1.1 Check if the lubricating oil level of bearing on both ends is normal;

7.5.1.2 Turn the pump shaft manually to confirm it is flexible and non-jamming;

7.5.1.3 Fill the pump with water and carefully check the sealing water cautiously to make sure

that the flow of cooling water is smooth and the air extraction valve is properly opened;

7.5.1.4 Power on after the insulation of LP Heater drain pump is qualified through measurement;

7.5.1.5 Close the outlet valve of LP Heater drain pump;

7.5.1.6 Start the drain pump and open the outlet valve of LP Heater drain pump (in the case of

outlet valve being closed and continuous operating time of pump ≯2min);

7.5.1.7 Put another LP Heater drain pump on “auto” position.

7.5.2 Shutdown of LP Heater drain pump.

7.5.2.1 Release the interlocking switch of standby LP heater drain pump;

7.5.2.2 Close the outlet valve gradually;

7.5.2.3 Stop the operation of drain pump;

7.5.2.4 Adjust the sealing water valve;

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7.5.2.4 When the pump shuts down for servicing, close all cooling system valves, sealing water

valves, air extraction valves and the pump outlet & inlet valves.

7.6 Check & maintenance in normal operation

7.6.1 Condenser:

7.6.1.1 Monitor the temperature rise of circulating water;

7.6.1.2 Monitor the differential pressure between inlet and outlet of circulating water;

7.6.1.3 Exhaust temperature of the condenser is not more than 80 ;℃

7.6.1.4 The temperature difference between both sides of condenser is not more than 2 ; ℃

7.6.1.5 Vacuum is normal;

7.6.1.6 The water level of condensate sump is normal.

7.6.2 Condensate pump

7.6.2.1 Sound is normal and there are no friction and vibration;

7.6.2.2 Check the outlet pressure of the condensate pump that shall be normal;

7.6.2.3 Check the leakage of condensate packing set that shall be normal;

7.6.2.4 The temperature of motor coil is normal;

7.6.2.5 Switch over condensate pump periodically.

7.6.3 LP Heater

7.6.3.1 There shall be no water hammer and vibration in the heater;

7.6.3.2 The water level of the heater is normal;

7.6.3.3 Check the temperature and pressure of the outlet and inlet on the water side of LP heater

that shall be normal.

7.6.3.4 Check the pressure and temperature on the steam side of LP Heater that shall be normal.

7.6.3.5 Check if there is no leak in the system.

7.6.4 LP Heater drain pump

7.6.4.1 There shall be a little thin flow of leakage, if it is excessive or none, it shall check and

adjust the tightness of filling in time;

7.6.4.2 The bearing oil level is normal. If it is low, add oil in time.

7.7 Abnormal operation of condensate system

7.7.1 In any case as follows, it is necessary to shut down the condensate pump for emergency

7.7.1.1 Much vibration occurs in condensate pump;

7.7.1.2 There is clear metal friction sound in condensate pump;

7.7.1.3 Motor has smoke belching and catches fire;

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7.7.1.4 Bearing has smoke belching;

7.7.1.5 Leak occurs in condensate pump that endangers personal and equipment safety.

7.7.2 Vaporization or air leak occurs to condensate pump

7.7.2.1 Phenomenon:

a. Outlet pressure of condensate pump fluctuates, the flow is unsteady or decreases to zero;

b. Motor current decreases or fluctuates;

c. Abnormal sound in pump body, vibration in outlet header and the check valve makes impact

sound;

d. Dissolved oxygen in condensate rises.

7.7.2.2 Causes:

a. Steam condenser water level is low;

b. Air leak in condensate pump inlet pipe;

c. Air leak in condensate pump packing, the sealing water valve is not opened or opened too little;

d. Inlet strainer of condensate pump is blocked;

e. Condensate flow is too low, and the recirculation valve is not opened.

7.7.2.3 Treatment

a. Check if the water level of steam condenser hot well is normal, if lower, make up water to

normal;

b. Check the condensate packing sealing water, and adjust the sealing water quantity to normal;

c. Check the air extraction valve of condensate pump that shall be on open position;

d. Open the condensate recirculation valve in time;

e. If adjustment fails, start the standby pump and stop the faulted pump.

7.7.3 Steam condenser water level abnormal

7.7.3.1 Phenomenon

a. Alarm for steam condenser being high or low;

b. Local water level gauge indicates high or low.

c. Overhigh condensate level will result in vacuum degree decrease, and too low condensate

level will result in abnormal sound or vaporization in condensate pump.

d. As water level of steam condenser rises to high value I, the standby condensate pump starts

by interlock.

7.7.3.2 Causes:

a. Condensate pump gets fault;

b. Leak occurs in steam condenser copper pipe;

c. Leak occurs in LP heater;

d. Deaerator water level control is out of order, or deaerator water level is abnormal;

e. Condensate piping gets leak or discharge valve mis-opens;

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f. Auto control device of steam condenser water level operates disorderly;

g. Recirculating valve of steam condenser is not closed tightly;

h. Overflow valve or water discharge valve of deaerator is untight or mis-opened.

7.7.3.3 Treatment of low steam condenser water level

a. Check if make-up water control valve of steam condenser operates normally, otherwise open

its make-up water bypass to make up to normal;

b. Check if water level control valve of deaerator is mis-opened large or jammed, if any, adjust to

normal in time.

c. Check if water discharge valve of LP heater #4 outlet is mis-opened, if any, close it in time;

d. Check if any leak in condensate system.

7.7.3.4 Treatment of high steam condenser water level

a. In case condensate pump gets fault in operation, it shall start the standby pump, stop faulted

pump, and contact maintenance personnel for treatment.

b. Check if make-up water control valve of steam condenser operates normally, if inlet water flow

is too large, if such, turn it down.

c. In case of leak in steam condenser brass pipe, check if the steam condenser half side leaks, if

serious, shut it down for treatment.

d. Check if condensate recirculating is mis-opened, if any, adjust recirculation in time.

e. In case of steam condenser water level rise, open the water discharge valve of LP heater #4

outlet so as to discharge to normal.

7.7.4 LP Heater is overfed with water

7.7.4.1 Phenomenon:

a. Alarm for high water level LP Heater;

b. The water gauge’s indication of LP Heater is high;

c. The current of LP Heater drain pump may decrease.

d. The condensate flow may reduce.

7.7.4.2 Causes:

a. The pipe of Heater leaks;

b. Drain governing valve works abnormally;

c. Drain pump of LP Heater woks abnormally;

7.7.4.3 Treatment:

a. When the water level of LP Heater is higher than normal level, it shall check if the operation of

drain governing valve is normal, otherwise open the emergency drain valve of LP Heater;

b. Check the LP heater drain water that shall work normally, otherwise start the standby drain

pump;

c. When the water level of LP Heater is II, the emergency drain valve of LP heater to condenser

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shall be opened;

d. When the water level of LP Heater is III, the protection operates, it shall close the extraction

check valve and steam inlet valve of LP Heater, parallel off and isolate the LP Heater;

e. When discovering the copper pipeline leaks, it shall be isolate and service it in time.

Chapter 8 Feed Water & Deaerating System

8.1 Starting conditions of the Feed Water & Deaerating System

8.1.1 If any case as follows, it is prohibited to start the feed water pump:

8.1.1.1 The main instruments meters (ammeter, speed counter, oil pressure gauge, Inlet & outlet

pressure gauge) lack or are damaged;

8.1.1.2 The outlet check valve of feed water pump is not closed tightly;

8.1.1.3 The protection test is unqualified;

8.1.1.4 The scoop tube is jammed or regulation failed;

8.1.1.5 The oil level of oil tank decrease to the limit value or oil quality is unqualified and oil

temperature is lower than 15 ;℃

8.1.1.6 The sealing water can not be put into operation normally;

8.1.1.7 The insulation of motor is unqualified;

8.1.1.8 The auxiliary oil pump fails or the lubricating oil pressure is lower than 0.17MPa;

8.1.1.9 The oil cooler of feed water pump has no cooling water;

8.1.1.10 Temperature difference between upper and lower pump body is higher than 20℃ as a

result of no warming up or poor warming up of feed water pump;

8.1.1.11 The water level of deaerator is low I value of 2,350mm;

8.1.2 The HP heater is forbidden to be put into operation if it has any defect as follows:

8.1.2.1 The water level gauge fails and can not monitor the water level;

8.1.2.2 The steel pipe of HP heater leaks;

8.1.2.3 The extraction check valve #1 & 2 are jammed or can not operate normally;

8.1.2.4 When the HP Heater protection, HP Heater emergency drain protection and extraction

check valve protection cannot be put into operation normally.

8.2 Check prior to feed water & deaerating system start-up

8.2.1 Cold start of deaerator:

8.2.1.1To ensure the overhaul of the deaerator and system has been finished, the work site is

clean, the equipment in good condition, the safety measures have been removed and relevant

work sheets have been packed up;

8.2.1.2 To check and confirm that every valve’s position is right;

8.2.1.3 Contact the heat engineer to confirm all meter’s motor-operated valves, water level

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gauges and protections are powered on and indicates correctly;

8.2.1.4 To confirm the water level and the higher-and-lower pressure signal can alarm well. The

motor-operated valves and governing valves switch can open and close flexibly and Open-Close

operating direction is correct;

8.2.1.5 Contact the chemist to prepare enough dematerialized water pump and start the

demineralized water pump, make up the makeup-water tank of condensate to the high level and

test the water quality that is qualified;

8.2.1.6 Supply steam to the auxiliary steam header, prior to which, it shall warm up and drain

water of the auxiliary steam header;

8.2.1.7 Ask the chemist to test the water level quality when the water level of the Deaerator

reaches 600mm. If the water is not qualified, discharge water until it becomes qualified. The

water overflow value shall be placed on the “AUTO” position;

8.2.1.8 When the water is qualified and the water level rises to 1,600mm, open the deaerating

valve of Deaerator properly;

8.2.1.9 Open the hand-operated valve of heating & steam inlet valve at the bottom of deaerator

slowly and put the bottom heating of deaerator into operation. Pay attention to controlling the

pressure of deaerator >P 0.15Mpa prior to supplying steam to the deaerator;

8.2.1.10 Control the water temperature at about 100 when the ℃ water level rises to the normal

point of 2,550mm.

8.2.1.11 After the steam turbine started, recycle the condensate after it is qualified, determine

whether to open the water inlet valve of condensate to deaerator according to the condensate

flow, and the condensate flow of deaerator thus to guarantee deaerating effect. At the same time,

put the auxiliary heating steam source into operation. Put the automatic control of deaerator

water level into operation in good time;

8.2.1.12 When the extraction 3 pressure of this turbine is higher than 0.25Mpa, put the extraction

3 into operation, close the auxiliary steam valve and close the hand-operated heating & steam

inlet valve at the bottom of deaerator;

8.2.1.13 The deaerator starts with the unit at sliding parameters, after the unit is in full load, check

the deaerator in an all round way that shall be normal.

8.2.2 Check and maintenance of feed water pump prior to start-up

8.2.2.1 Ensure the maintenance work has finished, the work site is clean and equipment pipe is

good;

8.2.2.2 Check if the position of all valves is correct;

8.2.2.3 Contact the heat engineer to supply power to all meters, protections and motor-operated

valves, test heat engineering signals and accident alarm sound that are good.

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8.2.2.4 The oil level of the oil tank is on the upper-limit the oil quality is qualified, when the

auxiliary oil pump operating, the oil tank temperature of hydraulic coupling is ≥ 15°C, oil pressure

within 0.17~025Mpa or so and 018Mpa minimally;

8.2.2.5 Drain out the gas in the oil and water pipeline of cooler and feed oil to circulate. When the

filter’s differential pressure is > 0.06Mpa, switch it to the cleaning side. The lubricating oil shall

keep on circulating until the strainer of filter is clean;

8.2.2.6 Check if the water level of the deaerator is normal, the temperature is > 50°C, the feed

water pump has a temperature difference between its upper and bottom pump body is lower than

20°C;

8.2.2.7 The sealing water system works normally and loop is smooth; Check if the pressure after

the sealing water governing valve is the ring is 0.05~0.1Mpa higher than the unloading water

pressure;

8.2.2.8 Check if all transmission contacts of hydraulic coupling speed governing mechanism are

firm transmitting reliably, and the handle is flexible, after it is normal through hand operation, set

the scoop tube at 0 position;

8.2.2.9 Power on the feed water pump motor after it is qualified through insulation test and it is

permitted to close the switch;

8.2.2.10 Close the water discharge valve of the feed water pump body;

8.2.2.11 Check if the recirculation valve is opened wide and set it on “AUTO” position.

8.2.3 Check and preparation prior to HP heater operation:

8.2.3.1 Ensure the check work is finished, the work site is clean the equipment pipeline heat

preservation is good, meters are all complete, report to the heat engineer to power on the meters

and protections;

8.2.3.2 Measure the motor insulation of all motor-operated valves that shall be good, qualified

and powered on;

8.2.3.3 Check if the system valves are on correct position;

8.2.3.4 Put the HP heater protective water source into operation and the pressure is normal;

8.2.3.5 Companying with the heat engineer to conduct relevant test and interlock tests to HP

heater that is good: extraction check valve ＃1 & 2 are normal through test, HP heater water level

protection is normal through test, and the HP steam inlet motor-operated valve and emergency

drain motor-operated valve are normal through opening/closing and interlock test;

8.2.3.6 Check and test that the HP heater drain auto-control valve’s opening and closing are

flexible, direction is correct, and automatic control is normal.

8.2.3.7 Check if the HP heater four-way valve is on the bypass position.

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8.3 Start-up of feed water pump set

8.3.1 All equipment of t feed water pump set and valves of pipe are checked and verified as

normal;

8.3.2 Confirm the inlet valve of booster pump is fully opened and the water discharge valve has

been closed;

8.3.3 Verify the feed water pump motor-operated outlet valve and the center tap valve is closed,

the recirculation valve of feed water pump is opened;

8.3.4 Verify the scoop tube of the hydraulic coupling is in the maximum position;

8.3.5 Verify when the auxiliary oil pump is working, the lubricating oil pressure is more than

017Mpa;

8.3.6 Click the “Start” button of feed water pump and record the constant speed’s time; if no-load

current is normal, then start the feed water outlet electric value;

8.3.7 After feed water pump starting, check the sound and vibration, etc. of the feed water pump

and booster pump that are normal;

8.3.8 When the lubricating oil header pressure is > 0.22MPa, the auxiliary oil pump shall stop

automatically;

8.3.9 Put the oil-cooler of motor into operation;

8.3.10 Put the oil cooler and lubricating oil cooler into operation according to the oil temperature,

and check if the cooling water flow, lubricating oil and the working oil flow are normal via the

observation hole;

8.3.11 Adjust the rotating speed of feed water pump, when the feed water flow reaches 280t/h,

check that the recirculation valve shall close automatically;

8.3.12 If another feed water pump reaches standby condition, put the interlocking switch into

operation;

8.3.13 Put-in of service oil cooler and lubricating oil cooler

8.3.13.1 Check every attachment and meter, and check if all joints are tight;

8.3.13.2 Open the oil valve on the oil side;

8.3.13.3 Close the oil valve on the oil side when there is oil overflowing;

8.3.13.4 When the oil temperature rises, put the cooling water on the water side of oil cooler into

operation, open the water discharge valve on the water side, and then open the inlet valve of

cooling water gradually;

8.3.13.5 The pressure on the oil side of oil cooler shall be larger that on the water side.

8.3.14 Hot reserve of feed water pump set:

8.3.14.1 Provide dynamic power and operating power for the feed water pump and the motor

insulation is qualified;

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8.3.14.2 When the auxiliary oil pump is operating, the lubricating oil pressure is >0.17Mpa;

8.3.14.3 Open the booster pump inlet valve, feed water pump outlet valve and the recirculation

valve;

8.3.14.4 The temperature difference between the pump body and feed water pump inlet is <

20°C;

8.3.14.5 The differential pressure of the sealing water of feed water pump is > 0.1Mpa;

8.3.14.6 The interlocking switch of feed water pump in on AUTO position, and the scoop tube’s

opening is on 60% position.

8.4 Start-up of HP heater along with the turbine

8.4.1 Prior to the unit start, the check of HP heater shall be done according to the preparation

done prior to operation, all steam inlet and water inlet valves are closed, steam & water discharge

valves are closed and protective water source of HP heater is put into operation;

8.4.2 After the feed water pump start, and the feed water pressure is more than 6MPa, check and

verify the emergency drain motor-operated valve of HP heater is on AUTO position, open the

water filler valve ＃1 and ＃2 on the water side of HP heater, open the air release valve on the

water side, close the air release valve on the water side after HP heater is filled with water, check

HP heater the HP four-way valve that shall open automatically, the feed water run along the HP

heater, close the water filler valve ＃1 and ＃2, check if there is no water level on the steam side

of HP heater that is normal and verify there is no leak in the HP heater;

8.4.3 After the water side of HP heater becoming normal in operation, open the drain valve of HP

heater #1 & 2 emergency drain to HP heater emergency drain flash tank, after turbine is latched,

open the steam inlet motor-operated valve and check valve of extraction 1 and 2, the steam side

of HP heater starts along with the turbine, in the process of unit impulsing and loading on, monitor

the outlet feed water temperature rise of HP heater that shall be within 1.83 /min℃ (110 /h℃ );

then open the continuous exhaust valve of HP heater;

8.4.5 Put the HP steam inlet valve, emergency drain motor-operated valve, extraction check

valve and HP protection into automation;

8.4.6 When the steam side pressure of HP heater ＃2 is more than 0.3MPa higher than the

pressure of deaterator, switch the HP drain to the deaerator and close the emergency drain

valves of HP heater ＃1& 2;

8.4.7 Adjust the water level of the HP heater and check if the automatic adjusting device of drain

is normal.

8.5 Cold start of HP heater

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8.5.1 Put the HP protective water source into operation;

8.5.2 Verify the inlet and outlet four-way value of HP heater are closed, feed water runs along the

bypass, the water filler valve is closed tightly and open the steam discharge valve on the water

side of HP heater;

8.5.3 Open the primary and secondary oil filler valve of HP heater to fill HP heater with water,

after there is water overflowing the air valve, close the air release valve on the water side of HP

heater, after the internal pressure of HP heater becomes equal to the feed water pressure, check

the HP heater four-way valve that shall open automatically, close the water filler valve, check that

there is no water level on the steam side of HP heater and verify no leak in HP heater;

8.5.5 Open the drain valves before and after the steam extraction section 1 and 2 check valve to

warm up the pipe;

8.5.6 Open the water discharge valve at the bottom of HP heater ＃1 & 2 HP heater, as well as

the air release valve on the top;

8.5.7 Open the check valves of steam extraction section 1 and 2;

8.5.8 Open the air inlet motor-operated valves of HP heater ＃1 & 2, maintain the HP heater

pressure within 0.05~0.1Mpa for warming, after there is steam coming from the air valve of HP

heater, close the air release valve of HP heater, and close the drain valves before and after the

steam extraction section 1 and 2 check valve;

8.5.9 Close the water discharge valve at the bottom of steam side of HP heater ＃1 & 2; open the

continuous exhaust valve of HP heater;

8.5.10 Maintain the differential pressure between HP heater＃1 and 2 at 0.5Mpa, open the air

inlet motor-operated valve of HP heater ＃2 & 1 gradually to control the average temperature rise

of the outlet water of HP heater >P 1.83°C, (sequence of extraction to be opened: ＃2 HP heater

air inlet valve-＃1 HP heater air inlet valve) until normal, pay attention to the water level of HP

heater, when the steam side pressure of HP heater ＃5 is more than 0.3MPa higher than the

deaerator pressure, it shall dump HP drain to the deaerator;

8.5.11 When the feed water temperature reaches the rating, open wide the air inlet valves of HP

heater＃2 & 1;

8.5.12 Put the HP protection, automation of the check valves and air inlet valves of extraction

stage 1 and 2, as well as “Auto” of emergency drain motor-operated valve into operation.

8.6 Normal shutdown of HP heater

8.6.1 Contact the unit supervisor to prepare for shutting down HP heater＃1 & 2;

8.6.2 Turn down the air inlet motor-operated valves of HP heater ＃1& 2 gradually (sequence of

extraction to be closed: ＃1 HP heater air inlet valve-＃2 HP heater air inlet valve), pay attention

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to that the feed water temperature decreasing rate must not be more than 1.83 /min℃ ;

8.6.3 When the differential pressure between the steam side of HP heater and deaerator is less

than 0.3MPa, switch the drain to the condenser, close the ＃2 HP heater drain and lead it to the

hand-operated valve of deaerator; close the continuous exhaust valve of HP heater;

8.6.4 Close the air inlet motor-operated valve of HP heater ＃1, close the extraction 1 check valve

fully, close the air inlet motor-operated valve of HP heater #2 and the extraction 2 check valve.

When closing the all, verify the inlet valve is closed tightly, then stop the water side of HP heater,

close the inlet & outlet four-way valve of HP heater with the feed water running along the bypass.

Check if the feed water pressure is normal;

8.6.5 Open the pipe of steam extraction 1 and 2 to drain water appropriately;

8.6.6 When there is a short time maintenance work on HP heater steam side, it is permitted to

operate with only the steam side stopped, but it shall verify there is no leak in the HP heater, and

open the water discharge valve on the steam side to discharge water until the steam side

pressure decreases to 0 prior to operation. It is forbidden strictly for HP heater to operate with

only steam side.

8.7 Sliding shutdown of HP heater along with the turbine

8.7.1 Intensify the monitoring and adjustment of HP heater water level when the unit sliding

decreases its load;

8.7.2 When the differential pressure between HP heater steam side and deaerator is less than

0.3MPa, switch the HP heater ＃2 drain to the condenser, close the drain valve of HP heater ＃2

to deaerator; close the continuous exhaust valve of HP heater;

8.7.3 After the turbine trips, check if the air inlet valves of HP heater ＃1 & ＃2 and steam

extraction 1 & 2 check valves automatically, and release the HP heater protection;

8.7.4 Open the drain valves of steam extraction stage 1 and 2;

8.8 Stop of feed water pump

8.8.1 Auxiliary oil pump is good through test run, and the sealing water and cooling water of feed

water pump are normal through check;

8.8.2 Release the interlocking of feed water pump and reduce its speed (if it is to switch over the

pump, it shall increase another pump speed to full load and switch over the center tap of feed

water pump);

8.8.3 When the feed water pump flow is < 132t/h, the recirculation valve of feed water pump

should open automatically, if not, open it by hand;

8.8.4 Verify that feed water pump, auxiliary oil pump, outlet valve and center tap valve are all on

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“Auto” position;

8.8.5 Start the auxiliary oil pump;

8.8.6 Reduce the rotating speed to minimal, set the scoop tube at zero point, and click the button

“Stop” of feed water pump to stop the feed water pump. Record the idle time;

8.8.7 Adjust the sealing water pressure to normal in time;

8.8.8 When the lubricating oil inlet temperature the decreases to 40 ,℃ turn down the cooling

water value of lubricating oil cooler. When oil temperature of the service oil cooler is 50 ,℃ turn

down the cooling water valve of the service oil cooler;

8.8.9 If it is to put the feed water pump into standby, open its outlet valve and check the check

valve that shall be closed tight and feed water pump is on “Auto” position;

8.8.10 If the feed water pump requires a maintenance, it shall ensure the auxiliary oil pimp to

operate for half 30min after pump stop and supply oil to cool the feed water pump.

8.9 Stop of deaerator

8.9.1 The stop of deaerator adopts sliding stop along with the turbine;

8.9.2 The pressure of deaerator sliding decreases along with load, pay attention to monitoring

and adjusting the water level of deaterator, and transfer the Auto into Manual adjustment if

necessary;

8.9.3 When the pressure of steam extraction 3 decreases to 0.25MPa, switch the steam supply of

deaerator to the auxiliary steam source;

8.9.4 Close the motor-operated valve and check value of this turbine’s stream extraction 3;

8.9.5 After the unit shutdown, stop the auxiliary steam source to deaerator. After boiler water

filling finished, stop condensate supply to deaerator;

8.9.6 When the deaerator requires water discharging, verify all steam valves and water valves

are closed tightly, open the water discharge valve at the bottom of deaerator slightly to discharge

water to the emergency drain flash tank.

8.10 Check and maintenance of the feed water & deaerating system

8.10.1 Check and maintenance of deaerator

a. It shall monitor the changes in pressure, temperature and water level from time to time when

the deaerator is normal operation. If any abnormality, adjust it/them back to the normal range;

b. When the condensate pump stopped because of fault, it shall start the standby condensate

pump instantly. If the inlet water of deaerator interrupts, it shall close the air inlet valve

immediately in order to prevent the deaerator from overtemperature;

c. It shall open the deaerating valve wider if there is not qualified oxygen content in the water of

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deaerator. It may open the heating & steam inlet at the bottom if necessary to adjust the oxygen

content to qualified;

d. Check the indication of the pressure gauge, thermometer and water level gauge of deaerator

on schedule, if any abnormality, it shall report for treatment in time;

e. If the water level decreases because of improper adjustment of water level or the condensate

pump’s insufficient output, it shall take some measures to make up water timely. But pay attention

to that: Don’t hurry, it may affect the pressure of deaerator and cause vibration. It may lower the

unit load if necessary;

f. If the water level still keeps on decreasing measures, it report to the unit supervisor. If

emergency water level occurs to affect normal operation of feed water pump and cause fault

hereof, it shall lower the load to shut down the unit;

g. Check the running condition of the safety valve of deaerator in operation regularly, when

deaerator is overpressed, pop the safety valve in order to ensure normal operation of deaerator.

8.10.2 Check & maintenance of feed water pump

a. Check if the feed water pump set has any friction and leak, vibration is normal and no

abnormal sound.

b. The oil level of oil tank and bearing is normal and the auxiliary oil pump is in good and standby

state;

c. All the protections have been put into operation, the automatic equipment works normally;

d. The sealing and cooling water system operate normally and the return water is unimpeded; the

sealing water governing valve can adjust automatically to make the pressure after valve have

always been 0.05~0.1MPa higher than the pressure before the booster pump inlet valve. At the

same time, maintain the return water temperature of sealing water within 70-80℃;

e. The coupling works soundly, and the speed governing mechanism is not jammed.

8.10.3 Check and maintenance of HP heater

a. HP heater water level is normal, and operation of automatic drain governing device is normal;

b. No water hammer and vibration;

c. Inlet and outlet temperature of water side is normal;

d. Temperature and pressure of steam side are normal;

e. No leak in the system through check;

8.11 Abnormal operation & treatment of the feed water & deaerating system

8.11.1 Abnormal operation & treatment of HP heater

8.11.1.1 Conditions of emergency stop of HP heater

a. Pipes and valves, etc. on the steam side burst, which endangered the personal and equipment

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safety;

b. Water lever of HP heater rises, treatment takes no effect and water level gauge is on the

utmost;

c. When water level gauge burst and can not keep on working;

d. The HP heater proper leaks seriously and cannot keep on working.

8.11.1.2 Treatment of t HP heater overfeed with water

Phenomenon:

a. Alarm for high water level of HP heater;

b. Protection may operate;

c. The HP heater outlet water temperature is low, and the heater vibrates.

Treatment:

a. When HP heater water level is high, check if the HP heater drain system operates normally,

when the drain governing valve is jammed, it shall open the emergency drain valve to lower the

water level, and contact with the maintenance personnel for treatment;

b. The running HP heater leaks and the water level rises to 850mm/1,125mm (HP heater＃1/ HP

heater＃2) sharply, the water level high value I alarm is raised;

c. If the HP heater water level rises to 1,000mm /1,275mm (HP heater＃1/ HP heater＃2), the

water level high value II alarm is raised to open emergency drain valve automatically;

d. If the Hp water level keeps on rising up to 1,200mm/1,475mm (HP heater＃1/ HP heater＃2),

the water level high value III alarm is raised, HP heater protection operates to close the feed

water inlet & outlet four-way valve of HP heater, as well as the extraction motor-operated valve

and check valve, open the water discharge valves on the steam side and water side and the air

release valve;

e. If the automatic paralleling off system of HP heater protection malfunctions and refuses to

operate, it shall parallel off the HP heater by hand immediately, if still no effect, it shall operate all

valves by hand locally immediately to parallel off HP heater;

f. When the HP protection operates to parallel off automatically, it shall pay attention to adjusting

the boiler combustion to prevent the initial steam from overtemperature or unit from overload.

8.11.2 Abnormal operation of deaerator

8.11.2.1 Deaerator pressure rise

Cause:

a. Air inlet interrupts or reduces;

b. The opening of governing valve of HP heater drain to deaerator is too large;

c. The unit load increases too quickly;

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d. Misoperation of system valve.

Treatment:

a. Increase the condensate flow, maintain normal water level to make the pressure recover;

b. If the opening is too large, adjust it in time;

c. Stabilize the unit’s load and decrease it properly;

d. Check if standby steam resource valve of deaerator is opened by mistake.

8.11.2.2 Deaerator pressure decrease

Cause:

a. Water Inlet flow increases suddenly or temperature decreases;

b. The steam source pressure of deaerator is too low.

Treatment:

a. Check if the deaerator steam source is normal, if not, transfer to the standby steam source;

b. Adjust the condensate governing valve according to the water level of deaerator.

8.11.2.3 Water level of deaerator rise

Cause:

a. Feed water pump trips, but the standby pump does not interlock or treatment is not timely;

b. The water level auto-governing system of deaerator malfunctions or the opening of condensate

governing valve is too large;

c. The water quantity used by the boiler decrease suddenly;

d. Mode of water filling is incorrect.

Treatment:

a. If the high water level I alarm of deaerator is raised, it shall turn down the governing valve of

condensate to deaerator;

b. When the water level of deaerator rises up to value II (2880mm), the overflow motor-operated

valve opens automatically;

c. Check if the feed water pump is started by mistake, if the mode of water filling is normal, if not,

stop it;

d. If the water level of deaerator rises up to the flood stage of 2950mm, the protection shall

operate, close the steam extraction check valve and motor-operated steam inlet valve of

extraction 3.

8.11.2.4 Water level of deaerator decrease

Cause:

a. The opening of the governing valve of condensate to deaerator is too small;

b. The condensate flow interrupts or reduces;

c. Feed water pump flow increases;

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d. The water discharge valve of deaerator is opened by mistake.

Treatment:

a. When the water level of the deaerator decreases, adjust timely the governing valve of

condensate to deaerator, or open wider the makeup water to maintain normal water level;

b. Pay attention to the change in condensate flow and maintain normal water level of condenser;

c. Stabilize the water quantity used by the boiler and pay attention the adjustment of the scoop

tube.

8.11.3 Abnormal operation & treatment of feed water pump

8.11.3.1 If any case as follows, the feed water pump protection will trip:

a. The deaerator water level is the low value II (680mm);

b. The differential pressure of sealing water is low;

c. The oil inlet temperature of the service oil cooler of feed water pump is > 130℃;

d. If the outlet flow of feed water pump is low (<132t/h), open the recirculation valve that does not

open after 15 seconds;

e. The librating oil pressure of feed water pump is the low value II (0.08MPa).

8.11.3.2 Conditions for emergency stop of feed water pump

a. The main feed water system leaks and a great deal of water spraying that cannot be isolated,

which endangered the personal and equipment safety;

b. Water pump, booster pump and hydraulic coupling vibrate violently;

c. There is metal impacting and friction sound between stationary and rotary part;

d. The feed water pump’s motor or bearing smokes and catches fire;

e. Oil system catches fire that can not be extinguished in time, which endangered the safe

operation of pump set;

f. Vaporization in feed water pump, and the outlet pressure and current oscillate greatly and

decrease;

g. The thrust bearing temperature rises up to 95 sharply℃ ;

h. Protection of feed water pump operates to trip.

8.11.3.3 Operating procedure of emergency stop of pump:

a. Start the auxiliary oil pump;

b. Press the emergency button of the faulted pump or open the console switch immediately;

c. Check the standby feed water pump that shall start to operate automatically, if not, start it by

hand. Check if the header pressure is normal, if it is the feed water pipe bursting, it shall be

prohibited to start the standby pump.

d. Close the outlet valve, recirculation and center tap valve of the faulted pump and open the

outlet and center tap valve of the interlocked pump;

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e. Record the idle time and vibration value of the faulted pump;

f. Complete other operations of pump stop, and take necessary safety measures as the fault may

be;

g. Report to the unit supervisor if there is no standby pump to shut down the unit for emergency.

8.11.3.4 Tripping off of feed water pump

Phenomenon:

a. The service pump’s current reaches “0”, the pump stops, emergency alarm is raised and feed

water pressure swings or decreases;

b. The standby pump interlock starts.

Cause:

a. Fault in the 6.6 KV busbar;

b. Protections of feed water pump and motor operate or are operated by mistake;

c. Misoperation made by man;

d. The emergency button is pressed by mistake.

Treatment:

a. Check and close the outlet motor-operated valve and center tap valve of the tripped-off pump,

check the auxiliary oil pump of the tripped-off pump that shall interlock to stop automatically;

b. If the standby pump doesn’t start, start it immediately, if no standby pump, or the standby

pump cannot be started by hand, it may recluse the tripped-off pump once more (when it doesn’t

reverse);

c. Adjust the interlocked pump’s rotating speed, put the feed water automation into operation, and

check if every part operating normally;

d. Check the recirculation valve of the tripped-off pump that shall be opened, and the recirculation

valve of interlocked pump shall be closed, otherwise operate by hand;

e. If no standby pump is available in the system, and the faulted pump can not start either, report

to the unit supervisor as soon as possible to conduct fault shutdown.

8.11.3.5 Vaporization in feed water pump

Phenomenon:

a. Abnormal noise occurs to the feed water pump’s inlet pipe or the inner of pump body;

b. Current and pressure of the inlet and outlet swing greatly;

c. Feed water pressure decreases.

Cause:

a. Deaerator pressure and water level decrease suddenly;

b. The inlet strainer is blocked;

c. When the flow decreases to the opening value of the automatic recirculation valve, but it fails in

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operating, for which the operation and treatment are not timely;

d. The inlet valve of booster pump is closed by mistake in operation.

Treatment:

a. Treat as per the requirements of emergency stop of pump;

b. Find out the causes for vaporization in feed water pump, and eliminate the abnormity;

c. If the vaporization is caused by inlet strainers of booster pump and feed water pump being

blocked, it shall start the standby pump immediately;

d. Only when the inlet pressure and deaerator pressure and water level become normal can it

restart the pump or put the standby into operation.

8.11.3.6 Feed water pressure decrease

Cause:

a. Fault in the hydraulic coupling or the scoop tube is jammed;

b. Water quantity used by the boiler increases greatly suddenly;

c. Water pipe breaks or HP heater leaks seriously;

d. The outlet check valve of standby pump is not closed tightly and the pump reverses;

e. The system valve is operated by mistake;

f. The service feed water pump is vaporized;

g. When the feed water flow is 280t/h, the recirculation valve of service feed water pump is not

closed.

Treatment:

The fead water flow exceeds 200t\h.The recirculation valve of the working feed water pump

hasn’t been closed.

a. If the feed water pressure decreases, it shall ascertain the cause quickly and report to the unit

supervisor at the same time;

b. If the feed water pump gets fault, start the standby pump quickly;

c. If the standby pump reverses, close the outlet motor-operated valve;

d. Stabilize the water quantity used by the boiler if the cause is sudden increase of water quantity,

adjust the speed of feed water pump and start the standby pump if necessary;

e. If the standby pump has interlocked, it shall adjust the rotating speed timely to prevent the feed

water from overpressure, after everything is normal, stop one feed water pump;

f. If the recirculation valve of feed water pump operates abnormally, contact the maintenance

personnel to treat.

8.11.3.7 Hydraulic coupling scoop tube being jammed

Phenomenon:

a. Adjustment to the scoop tube takes no effect;

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b. The feed water pump operates at a certain speed, which can’t satisfy the requirement of the

boiler or the rotating speed decreases.

Treatment:

a. Move the scoop tube locally to make it return to normal;

b. If moving the scoop tube locally is useless, it shall stop the faulted pump and start the standby

pump in time;

c. Contact the maintenance personnel, it must not restart or put the standby into operation until

eliminating the defect.

Chapter 9 DEH System

9.1 General statement of DEH system

DEH-steam turbine digital electric hydraulic control system adopts the I/A hardware manufactured

by FOXBORO company and uses HP fire resistant oil as its hydraulic pressure part, and the

governing valve is directly controlled by DEC with electro-hydraulic converter.

9.2 Structure of DEH System

With the operation of OPC solenoid valve and OPC oil way, HP oil system can realize overspeed

protection, and with the operation of diaphragm valve and safety oil interface, it can realize valve

fast closing as shutdown. That is the DEH system structure.

9.3 DEH operator station is to perform various operations and image operation with the

assistance of CRT picture, mouse, and keyboard. The main functions include:

Speed control: the operator realizes synchronous speed via turning speed according to the target

value and speed-up rate.

Overspeed protection test: perform OPC overspeed test under the control of DEH, moreover, and

it also has load rejection forecasting function.

Load control: after incorporating into network, DEH can realize the control of load and load

variation rate.

Automatic quasi-synchronization: At synchronous speed, it receives the increasing and

decreasing signal of “Automatic quasi-synchronization” device to accomplish unit paralleling and

paralleling off.

Remote control function: it receives the load command of MCS (analog value control) system to

realize coordination control.

Other functions: ATC control, valve position limit, lower limit of main steam pressure, high load

limit, steam extraction control, primary frequency modulation, and manual control, etc.

9.4 Conditions of steam turbine latching

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Steam turbine in the state of tripping;

Starting oil pump and EH oil pump operate normally and oil pressure is normal;

Manual shutdown is on the Reset position;

9.5 DEH Control and Operation

9.5.1 Automatic control mode (OA)

Operator can perform reset by clicking the button “Reset” on manual operation panel, and after

steam turbine is reset, main control panel will display “Latched”.

Click button “control mode” on top left of main control panel, and then sub picture of control mode

will pop up, here can select a control mode for application. Click the button “OPERATOR AUTO”,

afterwards click button “Put-in” within 3S, then auto control mode (OA) is put in, meanwhile, main

panel displays equipment being in “OPERATOR AUTO” mode.

Operator click the button “Limit Value” on lower left of main control panel to pop up the sub

window, then input valve position limit value, thereupon valve position limit will rising ceaselessly

up to valve position limit value.

Click button “Control Set Value” to pop up sub picture, input the target speed (0~3,000rpm/min)

into “target value” bar and the speed (0~500rpm/min) in “Speed” bar, afterwards click buttons

“ENTER” and “GO”, thereupon the set value will rise to target rotating speed according to the set

speed, then with PID calculating, #1~4 (valve regulating control signal) will come into being that is

transmitted to GV card to be transferred into current signal to drive electro hydraulic converter to

start the GV, which rotating speed will rise thereupon.

In case of auto mode in on-load stage, operator can set target load (0~135MW) and run up rate

(0~50MW/min) on rotating speed control sub picture through operating CRT, after click buttons

“ENTER” and “GO”, load set value will approach the target value step by step according to set

load rate, and then vary #1~4 (adjust steam valve control output), and change load can through

electro hydraulic converter operating hydraulic servomotor.

No matter it is the speed control stage or load control stage, once operator click button

“Maintain”, the rotary set value or load set value will maintain constant till operator press button

“GO”.

Attention: After latching, valve position limit must be opened before valve being opened.

9.5.2 Synchronization control mode (AS)

In auto mode, as rotating speed is close to 3, 000 r/min and self synchronization condition is met,

operator can press the control mode button in top left of main control panel to pop out the sub

picture, click synchronous button, afterwards click put-in button within 3s, then control will enter

the synchronous mode, meanwhile main panel displays equipment has entered “AS” mode.

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Then DEH will rise or decrease pulse according to the command received from electric aspect,

turbine set value will change thereupon. Each pulse can rise or decrease the turbine set value by

1r/min, and with internal PID regulator, DEH can control turbine rotating speed to change

thereupon, thus makes turbine rotating speed be synchronous with network.

After synchronization, DEH will let turbine load on 5% initial load automatically. In the meanwhile,

AS mode will disengage automatically and transfer back to OA mode.

9.5.3 Put-in and trip of power loop (MW IN, MW OUT)

In on load operation, operator can select to put power loop feedback into operation: operator can

click the button “Feedback state” on lower left of main control panel to pop up the sub picture,

then click button “power loop”, afterwards click “put-in” button within 3S, then control will enter the

power loop put-in mode, meanwhile the main panel displays device has entered to “Power loop

IN” mode,

After power loop feedback put-in, load signal will enter controller as feedback signal to control

load to be identical with set value (undisturbed switch). Prior to power feedback put-in, DEH is in

open-loop control, and there is certain difference between load set value and load, which is

decided by the current main steam pressure, if main steam pressure is the rated value, load set

value will be close to the load value.

Generally, operator shall select the power loop clearing mode in order to ensure the initial steam

pressure stable and boiler combustion adjustment stable. That is because after power feedback

put-in, when main steam pressure fluctuates, valve opening will vary thereupon to guarantee

developed power being identical with the load set value, and that vibration will accelerate

vibration of boiler outlet pressure, but in order to guarantee load steady, power loop put-in is

necessary.

9.5. 4 Remote control mode (ADS)

In on load OA operation, and the “set value” is close to the “remote control set value”, operator

can select to enter remote control mode: operator shall send out DEH remote control request,

then press the button “Control mode” on top left of main control panel to pop up the sub picture,

click button “Remote control”, afterwards click button “Put-in” within 3S, and then control will enter

the ADS mode, meanwhile the main panel displays device has entered to “ADS” mode. At that

time, load set value is under the control of CCS (Coordination control) system.

Attention: as entering OA mode, ADS mode will disengage automatically.

9.5.5 Initial steam pressure limit (TPL)

In on load OA operation, and initial steam pressure is higher than 90% rated pressure, operator

can select the TPL (initial steam pressure limit) mode: operator can pressure the “Limit value” on

lower left of main control panel to pop up the sub picture, then click button “Initial steam pressure

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limit”, afterwards click button “Put-in” within 3S, and then control will enter to TPL mode,

meanwhile the main panel will display the main steam pressure limit is “IN”

In the case of TPL mode, as initial steam pressure being lower than 90% rated pressure, load set

value will decrease at a fixed rate. Shut down the control valve hydraulic servomotor can

compensate the decrease of main steam, thus avoid initial steam pressure decrease being to

large.

TPL mode also can be cleared on limit at sub picture: click the button “initial steam pressure

restriction”, afterwards click button “Clear” within 3S, and then control will disengage from TPL

mode.

9.5.6 Remote control initial steam pressure limit (RTPL)

In OA operation, and the initial steam pressure is larger than 90% rated pressure, operator can

select the RTPL (Remote control initial steam pressure limit) mode: operator shall press the “limit

value” on lower left of the main control panel to pop up the sub picture, then click button “Remote

control initial steam pressure limit”, afterwards click button “Put-in” within 3S, and then control will

enter the RTPL mode, meanwhile, the main panel will display the Remote control initial steam

pressure limit being “IN”

In RTPL mode, and the initial steam pressure is lower than 90% rated pressure, load set value

will decrease at a fixed rate. Shut down the control valve hydraulic servomotor can compensate

the decrease of initial steam, thus avoid initial steam pressure decrease being to large.

RTPL mode also can be cleared on limit sub picture: click button “Initial steam pressure

restriction”, afterwards click “Clear” button within 3S, and then control will disengage from TPL

mode.

9.5.7 Load limit (HLL) mode

In on-load OA operation, operator also can select high load limit mode: operator can press the

button “limit value” on lower left of main control panel to pop up the sub picture, then input the

load set value in high load limit mode area, afterwards click button “High load limit”, and click

button “Put-in” within 3S, control will enter the high load limit mode thereupon, meanwhile the

main panel will display “IN”. In case of high load limit mode, set value will not exceed the load

limit value.

High load limit mode also can be tripped on limit value sub picture: click button “High load limit”,

and then click button “Clear”, control will disengage from the high load limit mode thereupon.

9.5.8 Valve position limit mode (VPL)

In OA operation, operator also can select the valve position limit mode: operator can click the

button “limit value” on lower left of main control panel to pop up the sub picture, click “valve

position limit”, then input valve position limit value in valve position limit mode area, afterwards

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click button “GO”, here valve limit value will enter the DEH control logic. In case of valve position

limit mode, valve command will not exceed the valve position limit value.

9.5.9 Single valve/ sequence valve (SIG/SEQ) mode

In case of OA operation, operator also can select SIGLE (single valve) or SEQ (sequence valve)

operation mode: click the button “valve mode” on milled lower part of main control panel to pop

up he side picture, click single valve (or sequence valve) and the two switching buttons (press

switching button within 3S after clicking single valve button, and it will be effective if the two

buttons being red synchronously.

In SIGLE mode, command of all the control valves is the same and all the control valves take part

in control synchronously; in SEQ mode, four control valves will operate one after another

according to a certain sequence. The switching time between two modes is about 3S so as to

guarantee no disturbance of load in the whole switching process.

9.5.10 OPC mode (OPC MODE)

Moreover, there is OPC (overspeed protection control) function set in DEH, in case load of steam

turbine is over 30%, and main oil switch of motor trips, at that time, with the function of solenoid

valve, all the hydraulic servomotors of control valve will control oil pressure to unload, thereby

closing all hydraulic servomotors of governing steams. With the quick close of hydraulic

servomotor, rotating speed acceleration will be restrained, and if steam turbine rotating speed is

lower than 103% rated speed, and it is already 7.5S after OPC operation, then solenoid valve will

lose excitation and hydraulic servomotor will start to maintain normal operation for waiting for

synchronization. If steam turbine rotating speed still is larger than 103% after 7.5S, the valve will

not open until steam turbine speed is lower than 103%.

9.5.11 Manual (TM) mode

It also can enter the manual control mode in steam turbine operation. Pay attention that in

manual operation, operator can change the set value (GVSPT/TVSPT) of control valve and main

steam valve directly without the participation of DEH, and this is belonging to open loop

operation, which is inappropriate to be used except rotating speed path fault, etc. special

situation. The method for entering manual (TM) is as follows: press the manual button on manual

control panel, if red lamp lights, that indicates device being in manual operation state, here

operator can click the control mode button on top left of main panel to pop up the sub picture, and

the manual state bar will display “IN”, meanwhile main panel will display device being in “TM”

mode.

In manual operation, operator can realize the control of steam turbine by controlling control valve

set value directly with operating the “GVUP” “GVDN” buttons on manual operation panel, thereby

change rotating speed and actual load.

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In TM mode, OPC function remains, once OPC operate, it still will close all steam governing

valves.

9.6 Stimulation Test of DEH

DEH has a built-in simulator that can perform closed-loop simulation test to DEH when the

turbine is in the state of rest.

It can stimulate control signals such as latching, synchronization, paralleling in and remote control

signal, etc. to carry static test to verify the signals or functions and ensure the smoothness of

impulsing.

Attention: this test can only be done by related personnel during outage and is forbidden in

normal operation of turbine. After the test is finished, all the original parameter must be restored,

otherwise a serious result may be caused; it is recommended to do this test in the engineer

station.

Chapter 10 Bypass System

10.1 Function of bypass system

10.1.1 Because of improving cold, warm and hot start conditions of unit that greatly reduces the

unit start-up time and makes unit operate with full load in advance, the bypass system is suitable

for the unit HP cylinder impulsing or HP & MP &LP cylinders combined start-up;

10.1.2 In the case of unit load variation, bypass system has governing function to coordinate the

steam quantity unbalance between boiler and steam turbine and bypass the excess steam of

steam turbine to stabilized the boiler operation;

10.1.3 In start-up, shutdown and load rejection, it can protect boiler reheater;

10.1.4 It can prevent overpressure and protect unit;

10.1.5 It can be used in working substance recovery.

10.2 Bypass put-in as unit starts

10.2.1 After checking over the system, ascertain the electro pneumatic devices are sound and the

bypass attemperating water pressure is normal;

10.2.2 Prior to bypass device put-in, open drain device of steam piping first to conduct piping

preheating and drain, check put-in of all the bypass instruments for normal;

10.2.3 Slightly open temperature and pressure releasing valve (about 2% of travel), afterwards

slightly open water spray control valve (usually HP bypass attemperating water is not put in),

observe steam temperature variation and ascertain water spray system is normal;

10.2.4 Open temperature and pressure release valve slowly to conduct preheating, maintain

steam pressure not more than 0.02~0.05MPa, generally speaking, the preheating time shall be

not less than 15min but can be reduced properly in case of lower start-up parameter;

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10.2.5 During bypass put-in, put HP bypass in first, then the HP bypass, regulate pressure after

governing valve and steam temperature to meet the requirement of start-up till outlet parameter

being steady and normal;

10.2.6 In unit shutdown, the temperature and pressure releasing valve, pressure reducing valve

and water spray control valve need to be open step by step according to operation parameter,

after unit shutdown, the above shall be closed in time.

10.2.7 Bypass device operating time is less than 8S at constant speed;

10.2.8 The max designed through flow of bypass system is 70%B MCR

Notes: six hydrodynamically-operated valves (including HP bypass pressure release valve, HP

bypass attemperating water isolating valve, HP attemperating water governing valve, LP pressure

release valve, LP bypass attemperating water isolating valve and LP attemperating water

governing valve), shall open automatically in case of unit fault (all are on the interlocking

position).

10.3 Shutdown of 70% bypass system

10.3.1 After unit loads on, bypass system shall be tripped according to the regulating requirement

of boiler parameter.

10.3.2 In bypass trip, HP bypass shall be tripped first, and then the LP bypass, the attemperating

water valve shall be closed first and then the pressure relief valve.

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Chapter 11 Turbine Proper Water Drain System

11.1 In order not to let the drain flow inversely, all drains are connected and arranged on the drain

header by pressure grade in order, the drain heater connects with the proper drain flash tank that

drains water to the condenser sump via pipeline at the bottom and connects with the throat part

of condenser via pipeline on the top.

11.2 In order to avoid accidents of water escaping into the ST and to reduce the loss of accidents,

all turbine proper drains and other drain valves related to the safety of turbine shall be operated

as follows:

11.2.1 Turbine proper drain shall follow the principle of starting by stages;

11.2.2 The drain on the upstream of turbine MP combined valve shall be kept open prior to the

unit is loaded up to 10% of rated load;

11.2.3 The drain on the downstream of turbine MP combined valve shall be kept open prior to the

unit is loaded up to 20% of rated load;

11.2.4 The drain on the upstream of turbine MP combined valve shall be kept open prior to the

unit is loaded down to10% of rated load;

11.2.5 The drain on the downstream of turbine MP combined valve shall be kept open prior to the

unit is loaded down to 20% of rated load;

11.2.6 Before opening the main drain valves, avoid breaking the vacuum, but this term is not

applicable to the emergency case requiring breaking vacuum.

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11.3 The turbine proper part includes the following drains:

11.3.1 Drain of cold and hot section of the initial and reheat steam pipes;

11.3.2 Drain of HP air duct;

11.3.3 Drain of MP air duct;

11.3.4 Drain of HP cylinder jacket;

11.3.5 Drain of valve level steam leakage;

11.3.6 Drain before and after HP exhaust check valve and extraction check valve.

Chapter 12 Quick Cooling System of Steam Turbine

12.1 Preparation prior to operation:

12.1.1 The quick cooling equipment is complete and useful.

12.1.2 Iron rust inside the heaters, gas collection tank and oil-water separator have been cleared

out thoroughly that are treated for corrosion protection, the strainer is reliable through check

which can ensure purity of air entering the turbine so as not to pollute the inside of turbine. Check

and verify the drain in cylinder and related pipes are all discharged so as to prevent drain from

dumping into the cylinder. Check if all metal temperature measurement points of cylinder are

sound. Check if the indications of cylinder differential expansion, expansion, axial displacement

and eccentricity, etc. are normal.

12.1.3 Operating of the safety valve of quick cooling equipment is reliable.

12.1.4 With the automatic control of heating air temperature that can control the temperature

deviation within ±5℃ and alarm in case of exceeding the limit, the temperature and flow

indicators and recorders are complete and useful.

12.1.5 Check if all valves of the quick cooling equipment and the system are in correct state.

12.1.6 Verify the circulating water system is put into operation and operating normally.

12.1.7 Verify the turning gear is put into operation and operating normally, shaft oscillation is not

more than 0.07mm and the indications of instruments are normal.

12.1.8 Verify the condensate system is put into operation and operating normally;

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12.1.9 Verify the air compressor and service air system are put into operation and operating

normally.

12.1.10 The manhole on the steam side of condenser steam side is opened. Check if the drain

valve before HP exhaust check valve is opened.

12.1.11 Only when the cylinder temperature decreases to below 350℃, it can put the quick

cooling equipment into operation.

12.2 Monitoring of parameters in quick cooling process:

In order to ensure the mental temperature inside the turbine can decrease evenly in the process

of quick-cooling after turbine shutdown so as to prevent overstress due to excessive cooling,

rotor from bending and cylinder and welded junction from deforming, it must strictly monitor the

changes in each point temperature, temperature difference between cylinder inner and outer wall,

temperature difference between upper and lower cylinder, absolute expansion, differential

expansion, axial deflection, rotor eccentricity, turning gear current, compressed air temperature

and flow and electric heater current in the process of putting the quick cooling equipment of

turbine into operation. The monitor control index of main parameters includes:

12.2.1 First stage metal temperature decreasing rate of HP cylinder is<5℃/h.

12.2.2 Carrier temperature decreasing rate of MP cylinder is<5℃/h.

12.2.3 Temperature difference between upper and lower cylinder of HP & MP cylinder is <42℃.

12.2.4 Indication of HP cylinder differential expansion is -2~+7.0 mm.

12.2.5 Indication of LP cylinder differential expansion is +6.5mm.

12.2.6 Rotor eccentricity is <0.076mm.

12.2.7 Turning gear current is normal.

12.2.8 Lubricating oil pressure is 0.12Mpa.

12.2.9 Cylinder expansion and contraction are smooth without sudden change

12.2.10 Control the compressed air flow within 25~80t/h.

12.2.11 After putt the quick cooling equipment of turbine into operation, , try to adopt no

temperature difference and little flow mode as much as possible in the early stage of air supply,

then slowly reduce the air temperature to keep the little temperature differences and increase the

flow to observe the change in the cylinder’s temperature. Strictly control the cylinder’s air inlet

temperature and ventilation quantity. In principle, keep stable for 30min every time of adjustment,

if there is no change or great change, make readjustment. The outlet temperature of air heater

shall decrease steadily without sudden change. When the air duct wall temperature of HP & MP

cylinder is about 100℃ and the first stage metal temperature of HP cylinder decreases by less

than 200 ℃, it may increase the ventilation quantity. When the first stage metal temperature of

HP cylinder and No.1 stator carrier temperature of MP cylinder reach below 140 ℃ and do not

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rise again obviously, it may end the forced ventilation. Close the air inlet valve and keep on

turning for 30min to see if the temperature of all points rises again, if not, it may stop turning to

start servicing.

12.3 Put-in of quick cooling equipment of turbine:

12.3.1 Put the LP cylinder spray of main machine into operation normally.

12.3.2 Slightly open the blowdown valve of oil-water separator and the drain valve of the gas

collection tank.

12.3.3 Open the total valve of compressed air.

12.3.4 Put the heater into operation.

12.3.5 Open wide the primary valve and adjust the air inlet flow of secondary valve as putting the

quick cooling equipment into operation. Slowly open the hand-operated air inlet valve of

compressed air to HP & LP drain pipe.

12.3.6 Open gradually the air inlet valve wider and set the outlet temperature of air heater

according to the decreasing of cylinder’s temperature, and control the temperature decreasing

rate not exceed 5 /h℃ .

12.3.7 Check if the exhaust temperature that shall not exceed 80℃.

12.3.8 In the process of put-in, check if the temperature difference between upper and lower

cylinder that shall not be more than 41℃.

12.3. In the process of put-in, pay attention to the change in cylinder expansion, differential

expansion and deflection.

12.3.10 Pay attention to the turning gear operating that is normal.

12.3.11 Keep various records.

12.3.12 If any abnormality, it shall stop air inlet of cylinder and report to the shift engineer.

12.4 Precautions in quick cooling operation:

12.4.1 Prior to forced cooling, purge the forced cooling system first up to standard and drain out

the water depositing in the system pipe.

12.4.2 In the case where turning gear of turbine is not put into operation, it is absolutely

prohibited to put the quick cooling equipment into operation; if so, stop the quick cooling system

immediately after the turning gear tripping.

12.4.3 Put the electric heater into adjusting the outlet steam temperature to warm up the system

pipe.

12.4.4 In the process of cooling, control the air inlet flow and outlet steam temperature strictly in

accordance with the specified decreasing rate, intensify monitoring, make adjustment from time

to time, control various parameters within permitted range and ensure safety of the unit.

12.4.5 In the process of forced cooling, it shall monitor and ensure normal operation of lubricating

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oil system, jacking oil system, turning gear, LP cylinder spray system and circulating water

system, if any system above stops, it shall stop forced cooling of turbine until the system

recovers.

12.4.6 In the process of forced cooling, intensify the monitoring of the operation of service

compressed air system at the same time.

12.4.7 In the process of cooling, if the decreasing rate difference between HP & MP cylinder

temperature is high, it may adjust and control with each branch valve.

12.4.8 It must not interrupt the compressed air as putting the quick cooling equipment into

operation so as to avoid dry heating of heater.

12.4.9 When the quick cooling equipment heater is in operation, pay attention to the operation of

heater, if air compressor stops or compressed air interrupts, it shall stop inlet of compressed air

and stop the quick cooling equipment.

12.4.10 When the quick cooling equipment is in operation, keep record of the turning gear

current, exhaust cylinder temperature, governing stage metal temperature of turbine, MP carrier

temperature, cylinder expansion, differential expansion, deflection and cylinder temperature, etc.

proper parameters once every half a hour.

12.4.11 In the process of quick cooling, it shall drain the water of steam-water separator, steam

bleeding box and gas container of air compressor and clean the filter periodically to prevent oil

and water dirty from entering the cylinder. Only in condition that the compressed air and flow are

normal, can the heater be put in to operation and can air be supplied to the turbine after the air

heater temperature becoming in accordance with the index. If discovering the air heater fails to

control temperature, it shall close the air source to prevent cold water supplied to turbine.

Precautions and parameter requirements:

a. When the governing stage mental temperature is 350-300 ,℃ the temperature decreasing rate

shall be less than 3 /h℃ and the temperature difference between hot air and mental shall be less

than 40 .℃

b. When the governing stage mental temperature is 300-250 ,℃ the temperature decreasing rate


than 60 .℃

c. When the governing stage mental temperature is 250-200 ,℃ the temperature decreasing rate


than 90 .℃

d. When the governing stage mental temperature is 200-150 ,℃ the temperature decreasing rate


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than 130 .℃

12.4.12 When air temperature exceeds the deviation or the electric heater loses power, it shall

raise the alarm and interlock close the inlet valve to prevent cold air from entering and cooling the

cylinder excessively, meanwhile cut off the power supply of heater to prevent the heater from dry

heating.

12.5 Stop of quick cooling system

After finishing quick cooling, adjust the potentiometer to 0 point manually, stop the heater, open

the power supply switch and continue to ventilate for 5~10 minutes, then close all valves. Slightly

open of the blowdown valve to prevent air leak of air inlet valve from resulting in water entering

the equipment.

Chapter 13 Air Cooling System

13.1 Brief introduction of equipment:

1

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Appendix Part

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Appendix 1: Comparison Table of the Pressure [P] & Temperature [th] of Saturated Water & Steam

P th P th P th P th P th

MPa ℃ MPa ℃ MPa ℃ MPa ℃ MPa ℃

0.0015 13.036 0.07 89.595 0.31 134.66 1.4 195.04 4.6 258.75

0.002 17.513 0.08 93.512 0.32 135.75 1.5 198.29 4.8 261.37

0.0025 21.096 0.09 96.713 0.33 136.82 1.6 201.37 5.0 263.91

0.003 24.1 0.1 99.683 0.34 137.87 1.7 204.31 5.5 269.93

0.0035 26.694 0.11 102.32 0.35 138.87 1.8 207.11 6.0 275.55

0.004 28.963 0.12 104.8 0.36 139.86 1.9 209.80 6.5 280.82

0.0045 31.035 0.13 107.13 0.37 140.78 2.0 212.37 7.0 285.79

0.005 32.898 0.14 109.32 0.38 141.71 2.1 214.85 7.5 290.50

0.006 36.183 0.15 111.37 0.39 142.62 2.2 217.24 8.0 294.97

0.007 39.025 0.16 113.32 0.40 143.62 2.3 219.55 8.5 299.23

0.008 41.534 0.17 115.17 0.41 144.52 2.4 221.78 9.0 303.21

0.009 43.787 0.18 116.93 0.42 145.39 2.5 223.94 9.5 307.21

0.01 45.833 0.19 118.62 0.43 146.25 2.6 226.04 10.0 310.96

0.011 47.71 0.20 120.23 0.44 147.09 2.7 228.07 11 318.05

0.012 49.446 0.21 121.78 0.45 147.84 2.8 230.05 12 324.65

0.013 51.062 0.22 123.27 0.5 151.84 2.9 231.97 13 330.83

0.014 52.574 0.23 124.71 0.6 158.84 3.0 233.84 14 336.64

0.015 53.997 0.24 126.09 0.7 164.96 3.2 237.45 15 342.13

0.02 60.86 0.25 127.43 0.8 170.41 3.4 240.88 16 347.33

0.025 64.992 0.26 128.73 0.9 175.36 3.6 244.16 17 352.26

0.03 69.124 0.27 129.98 1.0 179.88 3.8 247.31 18 356.96

0.04 75.886 0.28 131.20 1.1 184.07 4.0 250.33 19 361.43

0.05 81.345 0.29 132.39 1.2 187.96 4.2 253.24 20 365.70

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0.06 85.945 0.30 133.54 1.3 191.61 4.4 256.05

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Documents

135MW CFBC Operation Manual 1(20080306)