RAW MILL VERTICAL ROLLER MILL.pdf

沈阳重型机器有限责任公司 SHENYANG HEAVY MACHINERY CO., LTD.

2008-3-13 Operation instruction 1

1. APPLICATION

The vertical roller mill MLS3424A is used for grinding cement raw meal and the

raw material for building, chemical and ceramic industries.

2. SPECIFICATION

Plant data

Work capacity： 165t/h (wearing evening)

Feed size: ≤85mm

Feed water content: ≤12%

Wearable capability(consuming electricity guide line) ＜8.49kWh/t

Out feed size: <16%R 0.09mm

Speed of grinding track: 24.5rpm

Inching speed of grinding track: 0.5rpm

Main motor Type: YRKK710-6

Power: 2100kW

Voltage 6600V

Speed: 994rpm

Auxiliary motor

Power: 45kW

Speed: 1480rpm

Allowable volume of injection water into the mill (for three nozzles) : <7.5m3/h

(The actual volume of injection water into the mill is determined by the craft)

Pressure of injection water: 0.3Mpa

Temperature of injection water: <25oC

Total volume of using water: 28m3/h

Total installed power: 2300kw (approx.)

Total weight (excluding electric devices and driving units):327210kg (Not

including the weight of main motor、main reducer、electrical controlling device



and DSK-1600 three gates)

2.2 Technical characteristics for each component

2.2.1 Grinding rollers

Number of rollers: 3

Diameter of roller: 2450mm

Width of roller: 800mm

Grinding power of roller（one roller） 1235kN

2.2.2 Tension device

Hydraulic tension cylinder (with accumulator): 3sets

Operating pressure: 20Mpa

Structure of oil cylinder double function cylinder

Nitrogen pre-pressure of accumulator: (0.33-0.66) ×20Mpa

Oil cylinder working pressure 20MPa

Motor of hydraulic station:

Power: 7.5kW

Speed: 1450rpm

Power of electric heater: 2×2kW

2.2.3 Main reducer(Unsupplied, the purchaser should buy the main motor by

themselves according to the ordering require by bargainer)

Speed of input shaft: 994rpm

Speed of output shaft: 24.5rpm

Low pressure pump of hydraulic station:

Power: 2×15kW

Speed: 1450rpm

High pressures pump of hydraulic station:

Power: 4×15kW

Speed: 1450rpm

Motor for heated oil circulating loop:



Power: 4×6kW

Volume of cooling water through

Cooler: 45m3/h

Pressure of cooling water: 0.2Mpa

Temperature of cooling water: <28 oC

2.2.4 Classifier

Number of classifier vanes: 90

Range of speed: 9-90rpm

Motor type YP2280S—4

Power 75kW

Frequency conversion range 3～100Hz

Gear nominal transmission ratio: 17.77

Cooling fan type G280—A

Power 370W

Speed 1400r/min

2.2.5 Sealing air fan

Type of fan: MF10-19-13No6.2A sealing fan for cement mill,

Outlet : turn right 90°

Power of motor: 22kW

Speed: 2940r/min

Air flow: 3650 m3/h

Air pressure: 9000Pa

2.2.6 Overrunning clutch

Air used in cylinder: little (use when action)

Air pressure: 0.3Mpa

2.2.7 Auxiliary reducer (supplied by Flender, Germany)

Input speed: 1480rpm

Nominal transmission ratio: 77



Output speed: 19.22r/min

Speed of grinding plate: 0.5r/min

3. Design and functional description

3.1 Principle of operation

The rollers of the mill are pressed by hydraulic tension system. The classifier

is driven by frequency control motor, which is of variable speed. See fig. 1 for the

overall design of the mill.

Three grinding rollers are fitted under the pressure frame; the grinding roller

module is composed by thrusting component and splice joint module. The tension

force produced by three tension rods is transmitted trough the pressure housing

Discharge outlet

Shell of classifier

Frame

Hot air inlet

Hydraulic cylinder

Driving device of classifier

Lubricate oil

Dynamic vane of classifier

Static vane of classifier

Feed inlet

Pressure bracket Roller

Air ring

Table

Main motor

Auxiliary motor Auxiliary gear box

Main gear box Foundation



onto three rollers, then to the material bed between grinding roller and grinding

track, form forcing close annular body between the groundwork、tension rod、

frame 、grinding roller、 grinding track and reducer. An accumulator is fitted in

each hydraulic tension system as a shock absorbing system. The grinding track is

rotated by main drive through the reducer, and the grinding rollers are rotated

under the action of friction caused by grinding track. The grinding track turning

transmit the torque moment onto the frame trough the grinding rollers, then the

force is transmitted to the machine casing by pressure frame along circumferential

direction.

The material to be ground is fed to the mill down a feed chute on one side of

the mill into the grinding area where it is drawn in between the grinding rollers

and the grinding track and ground by compression and friction. It is then pushed

outward over the edge of the grinding track. The stream of gas flowing in all

around the nozzle ring can prevent the material falling down through the nozzle

and also allow the foreign bodies with high specific gravity to fall down through

the nozzle and be discharged out of the mill by scraper track. The ground material

to a certain degree of fineness is carried up by the stream to the classifier where

the oversize is separated out by gravity and centrifugal force. The finished meal is

discharged by air while the coarse particles are returned to the grinding track for

regrinding.

According to tests on site, it takes the feed material about 30 time’s

circulation (grinding-going up with stream-falling down-regrinding) before the

material reaches the finished fineness. Therefore the mill is also a high efficient

suspension dryer when grinding wet material with hot gas. The temperature goes

down from 300 ℃ at nozzle ring to 100℃ at the place one meter above the vane.

This is one of reasons why the MLS3424A mill can grind cement raw meal with

high moisture.

Compared with ball mill, the major advantages of MLS3424A mill are:



higher grinding efficiency, shorter process flow and lower specific power

consumption. Furthermore, the grinding of material is done under limited

pressure.

Since the mill housing is large, low flow rate can be obtained though the inlet

air volume is large. Based on this, the wear caused by injection and loss of

pressure is reduced; therefore the mill can be fitted with a small capacity hot gas

fan.

The grinding parts on grinding rollers and grinding track are replaceable

segments which are made of wear-resistant material.

3.2 Structure of a MLS mill

You can see from fig. 1 that the major components of a MLS424A mill are:

mill frame, mill foundation, grinding track, grinding rollers, tension system,

classifier and sealing air pipelines.

3.2.1 Mill driver

The mill driver consists of main motor, conical planetary reducer, low-speed

auxiliary reducer and auxiliary motor.

The main motor is three-phase asynchronous electric motor, air cooling,

started by liquid resistance.

The first stage of conical planetary reducer is of conical gear and second

stage planetary gear. The second stage is parallel shaft gear; the third stage is

planet gear. The output shaft is vertically mounted. Under the bottom of the

output shaft there are several babbitt thrust bearings. The reducer bears the

gravity of grinding parts and the vertical component force produced by tension

system. The shell of the reducer is of welding construction.

The first stage of auxiliary reducer is of conical gear and the second and third

stage cylindrical gear. The auxiliary drive slowly rotates the main drive via

auxiliary reducer and overrunning clutch. After the starting of main drive, the

overrunning clutch disengaged and auxiliary driving system shut down.

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3.2.2 Grinding track

The molten grinding track is placed and bolted on top of the reducer

according to transmitting torque moment. The removable grinding liner is

supported by the grinding track. The segments rest against the wedge-shaped rim

on the outer edge of the grinding track. On the opposite side towards the inner

hollow in the grinding track, they are fastened by clamping plates. The geometry

of segments determines the inclination of the grinding rollers, the angle between

the normal and vertical line at the contact point of grinding roller with segments

is 15 degrees.

The nozzle ring is located between the grinding track and the mill housing.

Gases flow through the inlet channel into the area underneath the nozzle ring

from where they are sucked upwards through the guide channels due to negative

pressure inside the mill. The material to be ground is spread to the grinding area

according to pre-determined direction resulting from the gases flow above the

nozzle ring and the action of pressure difference in the grinding cavity. Foreign

bodies that pass the guide channels fall into the area underneath the nozzle ring

where they are discharged out of the mill by a scraper. In case of material spillage

the cross-section of the nozzle ring can be reduced by covering the nozzles and

thus air velocity and lifting force can be increased.

3.2.3 Grinding rollers

The three stationary grinding rollers are staggered 120 degrees and fastened

with their pressure brackets to the pressure housing so that their being carried in

rocker mountings allows them to deflect on encountering obstacles in the

grinding track.

The body of grinding roller is made of steel plate by welding .The segments

of grinding liners are fastened by clamping plates, which are easy to replace. The

shielding plates are mounted on the outer surface of pressure brackets to prevent

the wear of bracket caused by fluid material.

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3.2.4 Tension device

Pre-loading of the grinding rollers is by hydraulic tension device. Pressure is

transmitted to the rollers via the pressure frame to which pressure yokes of the

rollers are fastened .The grinding force of grinding rollers is thus applied on the

material bed between grinding rollers and grinding track. An accumulator is fitted

on each hydraulic tension cylinder as a shock absorbing system.

Hydraulic system can also be used to lift the pressure frame. When doing this,

the plates which connect the pressure frame and grinding rollers should be

removed firstly and the grinding rollers should be fixed with handling tools. The

pressure-relief valve of hydraulic system should be down-loaded when removing

the plates which connect pressure housing and grinding rollers since the hydraulic

cylinders don’t have the pressure to lift the grinding rollers when acting upward.

3.2.5 Classifier

The mill is equipped with dynamic and static classifier to suit for more

abroad fineness requirements. Classifier is mounted on top of machine shell with

one rotary impeller. The rotary vane will be driven by frequency control motor 、

the reducer realize infinitely variable speeds, revolution of classifier can be

adjusted by frequency control motor. First time powder selection will be carried

out in still grid drum at outer side of rotary impeller

The higher of the classifier speed, the finer of the finished product and vice

versa. Since the fineness of the finished product is also affected by such factors

as temperature humidity and air pressure. It is impossible to find out the

relationship between speed of classifier and the fineness of finished product. The

relationship can only be determined during commissioning.

The classifier shaft is borne in a reinforced part of the classifier housing by

means of two self-aligning roller bearing and one axial bearing. The bearings

have no dust caps with them since the inside of their support is in sealed state.

The bottom of the classifier drive is sealed by means of the differential pressure

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between the atmospheric pressure and the negative pressure inside the mill. The

bearings are periodically lubricated by grease.

3.2.6 Mill frame

The mill frame consists of frames of welded construction, the joints of

frames are welded on site, the mill frame is provided with a maintenance door, an

access door and a manhole and three equally distanced water injection devices,

the mill base is welded with foundation plate and the mill frame is fastened to

classifier by bolts. Wear-resistant and replaceable liners are placed on the inside

wall of mill frame above the pressure frame to prevent the pressure frame from

damaging the inside wall of mill frame when it moves.

3.2.7 Sealing air part

The sealing air part prevents dust leaking into the grinding roller bearing

system. The sealing air produced by the sealing air fan inserted in to the grinding

roller bearings through the pipes mounted upon the mill housing. A knuckle joint

is fitted in the pipe in order to prevent the movement of grinding rollers to affect

the connection.

Since there is negative pressure in the mill and sealing air escapes from the

ring-shaped area, no dust can get into the sealing and bearing part. The pressure of

sealing air is monitored by means of contact manometers and pressure of sealing

air should not be lower than 5000Pa.

4. Operating

4.1 Preparations before starting the mill

When the mill has been down for any length of time, e.g. during repair work,

we recommend to check the connections of each part. The oil level of the various

units, the positions of various valves, etc. All supply units up to the mill feeder

have to be filled with material to make sure that material is supplied to the mill as

soon as the feeder is switched on. Otherwise there is a danger that the mill charge

is not enough. When the mill has been emptied, sufficient material has to be fed so

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as to provide a grinding bed of about 60mm.

4.2 Main items for Checking

The following items have to be checked before starting the mill;

Check that the oil filters of hydraulic units are not blocked; check that the water

pipes of oil coolers are not blocked.

Check that the pressure of hydraulic tension system is in conformance with the

values specified by the manufacturer. If not it has to be set according to the

instructions of the manufacturer.

4.3 Switch –on sequence

4.3.1 Open the ball valve (14) of hydraulic tension system, and then switch on the

power.

4.3.2 Switch on the oil heaters of reducer and the hydraulic tension system、three–flap

gate hydraulic unit.

Switch on the electricity heaters before the oil temperature of hydraulic unit of

reducer reaches 35℃ . Switch on the electricity heaters before the oil

temperatures of the hydraulic units of three–flap gate and hydraulic tension

system reach 20℃. In case of low ambient temperature heat up the gear and

hydraulic unit by hot air until the oil pump can be put into operation. When the

temperature indicated by contact thermometer of reducer exceeds 38oC, switch

off the heaters. When the temperature indicated by contact thermometer of the

hydraulic units of three–flap gate and hydraulic tension system exceeds 35oC,

switch off the heaters.

4.3.3 Switch on the sealing air fan motor.

4.3.4 Switch on the small oil pump in the classifier reducer.

Three minutes later, switch on the fan of motor drive and the motor drive of

classifier.

4.3.5 Switch on the low pressure pump when the temperature of reducer oil exceeds

38°C.

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4.3.6 Switch on the low pressure pump motor of reducer hydraulic station four

minutes later and when oil outlet pressure of low pressure pump reaches

0.1MPa, switch on motor of high pressure pump.

4.3.7 Switch on the intelligent pressure transmitter (11) of hydraulic tension system.

Switch on the oil pump motor (3) when the temperature indicated by the

thermometal thermometer (19) exceeds 20 . It is allowed to switch on oil ℃

pump motor only when the pressure of intelligent pressure transmitter (11) is

lower than 13MPa, and it will be automatically switched on when the pressure

is lower than this value during the operation of the mill, and oil pump motor (3)

will be shut down and the system is in pressure- keeping state when pressure of

intelligent pressure transmitter (11) is≥ 20MPa.

4.3.8 Switch on pump motor of three–flap gate (5) and electric liquid change-over

valve (19/1—3) when temperature of electric contact thermometer (2/1)

exceeds 20 . And there are three electric liquid change℃ -over valves in total,

and switch-on sequence is as follows: switch on electric liquid change-over

valve(19--1), which will disengage after 1.5 seconds; after 1/6 second, switch

on electric liquid change-over valve(19--2), which will disengage after 1.5

seconds; after 1/6 second, switch on electric liquid change-over valve (19--3),

which will disengage after 1.5 seconds; after 1/6 second, switch on electric

liquid change-over valve (19--1)… … periodically acts according to this

sequence and period of action is 5 seconds.

4.3.9 Switch on overrunning clutch. When switching on high pressure pump motor of

reducer hydraulic station and after two minutes later and when oil outlet

pressure of high pressure pump reaches (4-15) MPa, switch on change valve 2/1

and make cylinder motion and clutch joggle 1/1 and force stroke switch to

switch on.

4.3.10 If resistance thermometer temperature of static pressure bearing in reducer is

lower than 60 and after stroke switch of over℃ running clutch 1/1 is switched



on one minute, switch on auxiliary motor.

4.3.11 Switch on main motor. When pressure of 16 pressure switches in reducer

hydraulic station exceeds (4-15) MPa and auxiliary motor is switched on over

40 seconds, and change valve (2/1) of overrunning clutch is shut down over 7

seconds, switch on main motor. When revolution of main motor exceeds

output revolution of auxiliary reducer, overrunning clutch will automatically

disengage, and force stroke switch (1/2) switch on 1 second, that is, switch on

change valve (2/2) of overrunning clutch, auxiliary motor will disengage. In

order to guarantee the safety, set pin on overrunning clutch should be plugged.

Mill will be in normal operation state when all the various systems are in

normal operation.

4.4 Monitoring

4.4.1 Alarming

a. When the absolute vibration speed of vibration sensor mounted on the reducer is

more than 5mm/s.

b. Oil level in oil tank of reducer hydraulic station is lower than down alarming limit

or higher than up alarming limit.

c. When differential pressure of rough filter in reducer hydraulic station P △

≥0.05MPa.

d. When differential pressure of fine filter in reducer hydraulic station P ≥0.05MPa.△

e. Oil temperature of low pressure oil outlet in reducer hydraulic station t＞45°C or t

＜38°C.

f. When oil pressure of low pressure oil outlet in reducer hydraulic station

p<0.12MPa, it will send alarm, and at the same time spare pump motor starts, when

pressure p≥0.4MPa, spare pump motor shuts down. When pressure P>0.5MPa, it

will also send alarm.

g.When the temperature of resistance thermometer of five bearings in reducer is

higher than 60℃.

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h.When the temperature of resistance thermometer of four static pressure bearings in

reducer is higher than 60℃.

i. Oil pressure of high pressure oil outlet in hydraulic station of reducer P≥20MPa.

j. Low pressure pump motor in hydraulic station of reducer overloads.

k. High pressure pump motor of reducer hydraulic station overloads.

l. Differential pressure of heat exchanger in hydraulic station of reducer △P≥

0.1MPa.

m. Differential pressure of oil filter (5) in hydraulic station of tensioning device △P

≥0.35MPa.

n. Oil level of hydraulic level control device (16) in hydraulic station of tensioning

device is lower than alarm oil level.

o. Pressure of intelligent pressure transmitter in hydraulic station of tensioning device

P ≤11.5MPa.

p. Armor thermal resistance of mill roller bearing is higher than 100℃.

q. Differential pressure of oil filter (14) in hydraulic station of three-flap gate △P≥

0.35MPa.

r. When oil level of hydraulic level signaler (18) in hydraulic station of three-flap gate

is lower than the alarm position.

s. Any pressure of intelligent pressure transmitter of sealing air (1-3) is less than

5000Pa.

t．Anyone of three hydraulic pressure cylinders in three-flap gate has no action

within10 seconds.

4.4.2 Main motor shut down

a. When the absolute vibration speed of the vibration sensor mounted on the reducer

is more than 10mm/s.

b. Oil level of oil tank in hydraulic station of reducer unit is lower than down limit

oil level for shut down.



c. Oil pressure of low pressure oil outlet in hydraulic station of reducer unit is less

than 0.1MPa.

d. Oil pressure of high pressure oil outlet in hydraulic station of reducer unit △P≤

(4-15) MPa.

e. Temperature of resistance thermometers of five bearings in reducer unit is higher

than 65℃.

f. Temperature of resistance thermometers of four static pressure bearings in reducer

unit is higher than 65 .℃

g. Oil level of oil level control device (16) in hydraulic station of tensioning device

is lower than lowest oil level.

h. The pressure of pressure relay (10/4) of hydraulic tension system is not more than

10Mpa.

i. Oil level of hydraulic oil level signaler (18) in hydraulic station of three–flap gate

is lower than the lowest oil level.

j. Armor thermal resistance of mill roller bearing is higher than 120℃.

k. Any pressure of intelligent pressure transmitter (1—3) in air seal unit is less than

4500Pa.

1. Anyone of three hydraulic pressure cylinders in three-flap gate has no action

within15 seconds.

4.4.3 Tension device unlade

a. Automatic operation

The manual two-position-four-way change valve (8) is at working position, ball

valve (14) opens, switch on pressure relay (10/1) and solenoid valve (12).

b. Manual operation

Switch off the solenoid valve (12), open the ball valve (14) and place the manual

two-position-four-way change valve (8) in non-operation position.

4.5 Switch off sequence

4.5.1 The mill is normal operation.

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4.5.2 Switch off the main motor and the oil pump motor of three gates hydraulic unit.

4.5.3 Switch off the oil pump motor (3) of hydraulic tension system. Switch on the

solenoid valve (12). The system now begins to release pressure. Switch off the

solenoid valve (12) when P=0 and the solenoid valve restores its normal

position by spring. If manual operated, it will suffice to change the position of

the manual two –position-four-way change valve(8) .

4.5.4 Switch off the high pressure pump motor of reducer five minutes later after the

main motor is switched off.

4.5.5 Switch off the low pressure pump motor of reducer five minutes later after the

high pressure pump motor is switched off.

4.5.6 Switch off he small oil pump motor of classifier reducer three minutes later after

the motor drive of the classifier is switched off.

4.5.7 Switch off the sealing air fan motor.

4.5.8 Switch off power and water supply.

4.6 The lifting up and lowering down of pressure frame.

Since the hydraulic tension system is a pressure-keeping system, the oil in upper

and lower chamber of cylinder can not flow freely. Therefore, the following

works have to be done if the lifting up or lowering down of pressure frame is

needed.

4.6.1 Lifting up the pressure frame (manual operation)

Place the manual two-position-four-way change valve (8) in non-operation

position and close ball valve (14).

Manually start oil pump motor (3) and oil comes into the lower chamber of oil

cylinder as the pressure goes up, which results in lifting up the pressure frame

when the pressure frame is clamped or reaches the upper limit, the discharge

valve (13) acts as a protecting element. 4.6.2 Lowering down of pressure frame by its gravity

Place the manual two-position-four-way change valve (8) in operation position

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and close ball valve (14). It’s not necessary to start the oil pump motor (3) for

lowering down the pressure frame just slowly open the cut-off valve (7/3) and

the pressure frame will fall down slowly by its gravity. The falling speed is

adjusted by the cut-off valve (7/3).

See fig.2 for motion depicting and linkage relation of electrical element

when staring, monitoring, closing down and lifting and descending of pressure

frame. The numbers under electrical element at this diagram are the numbers at

its hydraulic system and air passage schematic diagram. See the No.10 segment

for hydraulic system and air passage schematic diagram. Among the rest, for

reducer hydraulic pressure station schematic diagram and three gates hydraulic

pressure station schematic diagram, please see their respective specification.

5. Assembly

5.1 Assembly of foundation parts

Foundation parts comprise all parts to be placed into the foundation on which the

mill together with the classifier and drive units are mounted.

5.1.1 Assembly of main equipment base

In order to be convenient for transportation, main equipment base is divided into

eight pieces (foundation frame, housing support, reducer base) for delivery, and will

be preassembled and marked in manufactory.

When mounting main equipment base, ground gauge and tape will be adopted for

measuring center location (refer to relevant assembly drawings), bottom hinged point

of tensioning device will be taken as reference during measurement, and main

equipment base should be measured by gradienter so as to guarantee the level degree.

Before main equipment base is mounted, all reference points (for example: mill

center) have been determined and confirmed by site engineer in charge of mounting,

and must keep identical with foundation scheme drawings. Foundation surface of one

time grouting should be cleaned, for example: cut steel reinforcement ribs that are

higher than plane to avoid interference with main equipment base. Pad for supporting

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I-bar and shims below main equipment base will be put at appointed location of one

time grouting top surface. And foundation bolt s and foundation bolt box will be put

in holes reserved for one time grouting, and then grout after correct location is found,

both level degree and standard height can be measured by gradienter.

Reducer base will be delivered in one piece, and distortion and surface scratch are

not allowed during transportation. Before mounting, anti-rust paint or other impurities

on machined surface of reducer base should be removed. Central location of reducer

base and central location of main equipment base must reach superposition (that is:

refer to bottom hinged point of tensioning device).

After reducer base that will be delivered in bulk and connecting plates of

foundation frame are screwed, readjust and level up reducer base and screw down

foundation bolts.

Then, mark on reducer base by chalk or paint, and measure by water level with

tolerance of 0.05mm/m, and it can be adjusted by using pad if not reach tolerance

requirements. First, measure four corners on reducer base, adjust I-bar if deviation is

big, if within tolerance range, that is, measure other measured point in top plane and

make a record.

After main equipment base is put into foundation, additional steel rib bunch for 30

holes with diameter of 180 on main equipment base will be hanged, and vertically

pointing to foundation. Additional steel rib bunch for 12 holes with diameter of Φ125

on reducer base will be hanged, and vertically pointing to foundation.

After aforesaid work is finished, reducer base and foundation frame will be

welded according to relevant assembly drawings. And supporting base of housing and

foundation housing will be welded. After welding, distortion should not occur. And

remeasure reducer base and level up, if distortion occurred due to welding, it is

suggested to grind surface and maximum is 0.05mm/m (arithmetic average value).

When reducer base, foundation housing and housing base are mounted and

finished adjustment, second time grouting can be carried out for these pieces.



According to design requirements of drawings, distance between top plane of second

time grouting and top plane of reducer base should be less than 25mm and concrete

must go through sufficient vibration in vibrator so as to fill in the whole space. Notes:

this is only grouting for inside of reducer base, concrete passes central grouting

entrance from top and enter reducer base.

5.1.2 Assembly of motor foundation

The motor foundation is delivered to locale integrally.

Firstly, clean one time grouting concrete surface, and set foundation bolt

boxes(Make sure the setting place is what drawing requests), foundation bolts and

I-bar spacer and washer required by the same method of setting main machine support.

Secondly, set motor foundation, and adjust its axial direction, height, center line by

appropriate apparatus, then weld it on reducer foundation, and grind to smoothness

after welding. Then hang tendons at 46 holes of Ф50, making them extend in base.

After finishing the above work, weld reinforcing-bar and component in

foundation bed.

5.2 Assembly of mill components

Mill components are those parts which are mounted on the foundation parts.

5.2.1 Reducer

The reducer of the mill serves as a support of the grinding parts and as a means of

speed reduction of the mill motor. The reducer is a very important and heavily used

component of the MLS mill. The quality of main contact surface of reducer should be

ensured during transport and assembly. The reducer should be conveyed integrally,

and auxiliary reducer, overrunning clutch and reducer hydraulic pressure station

should be conveyed singly.

5.2.2 Assembly of reducer

Prior to its assembly and transportation to the mill foundation the reducer has to

be lifted by means of hydraulic pumps or other adequate lifting devices in order to be

able to check whether the reducer bottom is absolutely clean and smooth. Ensure that

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the reducer is wedged and secured against dropping or skidding before the underside

is checked. The reducer base has to be free from dirt and remaining protective paint.

And check the reducer base for any unevenness such as hammer blows center punch

marks etc.

Place the I-bar (80mm height) on the slide rails and the I-bar can be tack welded

at the unimportant points on the slide rails. Then the reducer is pushed on top. And

stack up enough rolling bars which diameter must be more than 60mm, and which

surface must be smooth. The reducer is drawn onto reducer support by gin type tools.

Put all bolt holes in order, and jack reducer up by hydraulic jack in order to shift the

rolling bars out. Check that the contact surface is smooth or not again. Put down the

reducer, and check the gap between contact surfaces by spacer gauge. The maximal

gap shouldn’t be more than 0.05mm. The adjusting pins are embedded after adjusting

the place and gap of reducer. The T type bolts are screwed down by limiting moment

spanner. After assembling bolts and pins at reducer and support, wedge them by

wedge iron.

Consult assembly specification of reducer for its detailed assembly instructions.

5.2.3 Assembly of hydraulic cylinders with pressure accumulators

For reasons of an improved accessibility we recommend that the three hydraulic

cylinders with the pressure accumulators are mounted in the tie rod eye provided for it

at the foundation housing before the mill base is assembled. Please pay attention to

the distance rings.

5.3 Assembly of frame

At one hand, frame is the support of classifier and contains reducer. At the other

hand, frame can guide direction of sirocco, collect and d remove impurities and heat

insulating layer is also filled in the frame.

5.3.1 Assembly of frame

Because of restricting of transportation condition, the frame is disassembled to

six segments and conveyed to locale. But it should be preassembled at production

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plant, and bolting plate should be saved in order to spotting when welding on site.

Each segment is carried on support of main machine, and set well according to

the method which drawing requests. The six segments of frame are bolted at position

of bolting plate by bolt. Then the frame is azimuth adjusted and localized spot

welding.

5.3.2 Adjustment of frame

The frame is now aligned axially and centrally to the mill center. The longitudinal

and crosswise axis with the fixed axes of the mill foundation and gearbox is plumbed

by means of a sounding lead. It is of major importance that the center of the frame

corresponds to the center of the reducer. The permissible tolerance amounts to a

maximum 0.5mm.

5.3.3 Welding of mill frame

Once the mill frame is aligned it is welded the six parts together according to

corresponding drawing, rubdown the inferior extremity of the weld bond, cut off the

plywood, then weld the frame on the main equipment base. Erenow, weld insulation

bed and weld ported air ring bracket according to the drawing.

5.3.4 Pouring of main equipment base

After aforesaid work is finished, that is, pouring of the whole foundation should

be intact and foundation should be provided with smooth surface.

After pouring concrete, heat insulating material should be mounted in the heat

insulating layer of the frame, and it should be paid attention that bolt head must not be

exposed outside the plane, otherwise scraper will be scratched.

5.4 Assembly of grinding track

The grinding track is delivered in one part. Once the grinding track is brought to

the mill foundation it is to be placed on a stack of wooden beams or ties which should

have a height of approximately one m.

5. 4. 1 Assembly of grinding track seat

The bottom flat of grinding track and the top flat of reducer should be cleaned

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before assembly, and the rabbet dimension is measured again, then the assembly bolt

pins are screwed on grinding track seat. At this time, the grinding bowl is hoisted and

set on reducer by hoisting equipment. The maximal space between grinding track and

reducer is 0.1mm before screwing down bolts. The grinding track seat couldn’t be

declining in order to prevent disable of rabbet plate. Finally bolts are screwed down

by limiting moment spanner.

5. 4. 2 Assembly of sealing cone

The sealing cone should be assembled after assembling grinding track well.

Firstly bolt each part on grinding bowl by bolt, then carry out welding.

5.4.3 Assembly of scraper

As an assembly part, after scraper is assembled well, it should be screwed down

on grinding track by bolt. At this time adjusting the gap between scraper bottom and

heat insulating layers should be noticed.

5.5 Mounting of tensioning pole bracket and frame flange

According to the drawing requirements, weld the tension pole bracket firstly, and

in accordance with the location marked in the drawing, the frame flange which are

divided into three parts will be connected by using spring column pin and some

flanges below classifier, then mount it on the frame, after adjustment, it will be

welded on the frame. Before this, asbestos cord for seal should be put between flange

below the classifier and frame flange and then dismantle bottom of classifier and

carry out welding.

5.6 Assembly of grinding track liner

The grinding track liner is a wearable part of mill. It bears corrosion which is

brought by milling force when mill running.

The contact between liner outside grinding track and grinding track seat should

be well. The contact surface between liner and clamping plate should be smooth.

The grinding track and liner should be cleaned before assembling liner. The

adjusting pins should be embedded the corresponding holes according to drawing

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after cleaning. Then the T type bolts are embedded. It should be noticed that the gaps

between several liners at circle are approximately identical. Then the clamping plate

should be assembled and screwed down by limiting moment. Finally several wedge

washers are added to the gaps between liners.

After finishing the above work, the shield at middle of grinding track should be

assembled according to drawing.

5.7 Assembly of nozzle ring

For transportation reasons the nozzle ring is dispatched in three parts, after

arrived, weld the three parts together and adjust the position, then assemble back

block.

Once these works have been completed the nozzle ring is brought in to the mill

and placed onto the nozzle ring supports mounted on the mill base. The nozzle ring is

centrally aligned with the grinding bowl, adjust height、level and center position. A

divided square ring supplied loosely which is to decrease the air gap between nozzle

ring and grinding track, adjust the radial position, and welds the ring on the inner cone

of the nozzle ring finally.

After adjusting position, wedge it by slide wedge and weld the slide wedge on

the wall of the bracket. Weld nozzle ring bracket、skims and nozzle ring together,

finally seal the nozzle ring and bracket by sealing cord, put on the clamping plate.

5.8 Assembly of pull rods

The pull rods and some associative components are delivered in bulk; some

coupling fastening pieces have to be greased before delivering. When assembling,

firstly input the pull rod into the pull rod seat of the bracket, then a screw thread is

enclosed for screwing the sleeves on the pull rods and pistons, and the upper slide rest

is joined with pressure frame by splice joint.

5.9 Assembly of grinding rollers

The tree grinding rollers are displaced by 120 degrees but are mounted stationary;

any grinding roller has rotation around its mandrel, but has not revolution. In fact, the

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position of the grinding roller has already decided by the position of the assembled

tension device.

The grinding rollers are assembled completely with bearing system, grinding

roller segments and pressure yoke but are delivered without oil filling. In case a

longer delivery time is foreseen or requested by the customer (a min. 1 year before

commissioning) the bearings are preserved.

A single conic assembly ring is included in the delivery of the three grinding

rollers. This assembly ring is not to be employed for the assembly works but is an

auxiliary tool to be used for a possible repair of the bearing system or for the changing

of the radial shaft sealing rings. Furthermore a suit of handling tool which is used to

assemble grinding roller is delivered at the same time.

5.9.1Assembly of pressure brackets on the roller axles

Before the grinding rollers are mounted into the mill, if the grinding roller and

roller bracket are delivered as spare parts, you should assemble the roller bracket on

the grinding roller. Firstly, put the closed type sealed cap adown, clean out the dirt on

the constructional surface, pull the bracket to the locating surface, screw down the

guard board by bolts. When placed guard board, you should collimate the lubricant

hole and oil plug.

5.9.2 Assembly of grinding roller into the mill

The assembly of the grinding rollers into the mill requires a grinding roller

support. The grinding roller support is assembled according to drawing “Assembly

Device”.

Lift the grinding rollers into the mill by means of steel cables of the same length

hung in the hooks which are cast at the pressure brackets. When assembling the

grinding rollers try to place them in such a way on the grinding plate that roller tire

center and grinding track center are congruent.

Once the grinding roller is placed on the grinding plate hang the grinding of the

installation device into the supports at the pressure yoke. Ensure that the grinding

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roller is inclined by 15 degrees. A secure position of the grinding rollers on the

grinding plate necessarily requires a locking of the grinding roller on the grinding

plate with wooden wedges.

5.10 Pressure frame

The pressure frame transmits the pressure onto the grinding rollers. The pressure

brackets of the grinding rollers are supported below the pressure frame and connected

with it by articulation parts. At each corner of the pressure housing a pull rod with

fork-shaped piece is connected. Its three-part design and the articulated suspension of

the pull rods ensure an even pressure distribution on the three grinding rollers. For

transportation reasons the pressure frame is usually delivered in three parts.

5.10.1 Assembly and welding of the pressure frame

The pressure frame has already been assembled once, numbered and

stress-relieved by the manufacturer. In order to ensure perfect welding on site the

three-part pressure frame was assembled by the manufacturer. In such a way that the

distance between the individual parts provides for a good root weld joint.

Distance pipes are included in our scope of supply in order to enable you to keep

the exact distance on site; you should pay attention to the sign of the manufacturer,

and then weld the pressure frame together according to corresponding drawing. After

welding, cut off the redundant sections on the distance pipes by gas welding and

burnish the cut.

Before the pressure frame is brought into the mill, the footstep、ball and socket、

splice jointing base of the tension device must be assembled and keep the interface

contacting well, assemble the splice jointing base on the frame.

5.10.2 Adjustment of the pressure frame

Firstly, assemble the adjusting plate and wearing plate of the three corners, bring

the pressure frame into the mill by three isometric wire cables, and collimate the

pressure frame and cylindrical roller on grinding roll by adjusting the handling tool.

After the pressure frame is completely adjusted, splice joint the grinding roll bracket

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and pressure frame by six connecting plate.

After the work has completely done, center the pressure frame and adjust the

clearance between the pressure frame and frame.

5.11 Hanging the pull rods into the pressure frame

The hanging is to be carried out according to drawing tension device.

The assembled pull rods have to be inserted into fork-shaped pieces by means of

a winch or a grab host, and then the articulation support with ball is inserted and

locked with locking plate and shackle.

5.12 Assembly seal air piping

It is of no importance for the further assembly whether the inner sea air piping

that goes with the grinding rollers or the outer seal air piping that goes with the sea air

fan is assembled first.

5.12.1 Assembly of the seal air pipelines within the mill

Insert the seal air pipelines that go with the grinding rollers into the wear

bushings of the flange bearings with the end carrying the articulated inner rings that

have been assembled by the manufacturer. The other end carries the elbow joint and

articulated bearing that has been assembled by the manufacturer. This end is screwed

tight with the pressure brackets of the grinding rollers. Don’t forget the sealing

element.

5.12.2 Assembly of the seal air pipelines outside the mill

Fix the collecting piping at the mill frame by provisionally screwing the welded

clips to the underside of the mill frame flange. Now the three connecting pipes of the

collecting piping have to be fitted to the flange bearings and the flanges have to be

welded to the piping.

After the completion of these works assemble the seal air fan with the suction

filter and drive motor according to the arrangement plan. When doing so align the fan

horizontally and vertically, nipped by special pipe clamps in proper position. Weld

each pipeline and elbow. In order to reduce the mainframe’s disturbance which cause

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by the libration of the fan, using a tube.

Access three measuring pipelines and three pressure transmitters, the direction of

pipeline and the position of frame can be decided by the user.

The measuring pipes are connected by welded flange and splice jointed flange of

the frame.

5.13 Assembly of hydraulic pipeline for tension device

Pipe clamps in hydraulic pipeline of tension device should be carried to locale in

bulk.

The pipe clamps with base are disposed on the outside of the bottom of the frame

according to the graphics or field situation, every pipeline muse be bent according to

the field situation. All pipelines must be cleaned before assembling. Once all the pipe

work has been completed the whole piping system has to be flushed with hydraulic oil

in order to prevent any rust.

5.14 Assembly of classifier

5.14.1 Assembly and mounting of classifier bottom part

In order to be convenient for transportation, the classifier bottom part are

divided into several parts, but it is required to be pre-assembled with the frame in the

manufacturing plant and make marks. Weld connecting angle steel and screw the parts

with bolts, and can be deliver to site after dismantling. First: assemble flanges of

every part and frame flanges, and then bolts and spring column pin, before this,

asbestos rope for sealing should be put between flanges below the classifier and frame

flanges, then screw them by using angle steel for connecting and bolts and carry out

welding, cut angle steel after welding and welded grooves and cut opening should be

ground flat.

5.14.2 Assembly impeller

The impeller is carried to locale in the whole part, then fix vanes on impeller,

fasten by boils, put the impeller on the appropriate height of the trigonal frame.

5.14.3 Assembly and mounting of classifier top part (according to drawing “Classifier

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Bottom Part”).

Like the classifier bottom part the classifier top part is also delivered in several

parts and assembled and welded on the ground or on the classifier bottom part

according to the numbers indicated. Screw bell housing to classifier bearing according

to drawing. Place it into the classifier, align it concentrically, mount reinforcement

and strutting and weld tightly. Observe welding instructions on the drawing ‘Classifier

Top Part’.

Then assemble the speed gearbox and the motor drive.

5.15 Assembly of mill actuating device

According to drawings “Foundation Plan” 、“Slide Rails” and “Motor Support”.

5.15.1 Assembly of coupling main motor and reducer

The machine use diaphragm coupling, made in CHINA. Please observe their

mounting and operating instructions.

5.15.2 Assembly of auxiliary reducer and overrunning clutch

An overrunning clutch (claw clutch) serves as a coupling between auxiliary

reducer and main motor; it should enclose the distance ring on the motor shaft before

assembling the overrunning clutch.

The central position of assistant reducer is adjusted by washers, and then

assembles the overrunning clutch.

Drilling pin holes between the assistant drive base and main engine foundation,

then drive into pins after well adjusting the assistant reducer.

5.15.3 Assembly of main motor

Once both coupling halves (one flexible coupling and one overrunning clutch)

which have been supplied for the main motor are assembled on the shaft ends of the

main motor, the main motor can be mounted. It is lifted on the motor support by

means of a hoist or any other adequate lifting tool and is aligned. The adjusting of

central height is accomplished by washer, but the position of axial direction is

adjusted by the round holes in the base. It is better to use thick washer not several thin

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washers when there is fair-sized warp. In order to adjust the position of the main

motor, we can assemble casual adjusting bolts in several directions to adjust the

position, and then they are dismantled after well adjusting.

Eventually, after all assembly works at the mill actuating device have been

completed, use taper pins or dowel pins in according to mounting instructions of

manufacturer, then the coupling guards have to be mounted and fastened.

5.16 Assembly of indicator

Each indicator is assembled under the three tension studs of the tension device,

in order to control and master the height of layer in the mill.

The pointer is fastened on the tension stud by bolt, the position of the pointer is

confirmed with the zero position on site, then arranges the circumference position in

term of easily observed. After arrangement, make screwed hole on the frame.

5.17 Mounting of temperature measuring device for mill roller

Temperature measuring device for mill roller is to monitor temperature changes

on bearings of mill roller so as to protect mill roller bearing.

Screw temperature measuring elements of temperature measuring device into

mill roller shafts, and its conductive wire is laid from roller bracket and along air

sealing pipeline.

Spot weld single pipe clamp on the air sealing piping, conductive wire of

temperature measuring device goes into piping clamp and finally come out from the

hole drilled at site which is at nearby of the frame, which connects air piping with

mill.

It should be paid attention to when mounting temperature measuring device for

mill roller, its guiding piping should be put on top of pipes of air sealing piping to

prevent from erosion by wind and raw material.

6. Commissioning and test run

6.1 Commissioning personnel

The following items shall be settled before the start of commissioning by and

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between supplier and customer.

1) Number of commissioning engineers, electric engineers and mechanical

engineers.

2) Number of fitters, electric technicians and operators.

6.2 Equipment for commissioning and performance tests to be provided by the

customer

1) A minimum four U pipes to measure the negative pressure in the plant (up to

1,500 mmH2O).

2) Pilot tube with inclined-tube manometer for air volume measurement

3) Electric thermometers (measuring range up to +500℃) for temperature

measurement of gas, surfaces, and material.

4) Measuring sockets in the pipelines for measurements 1-3, to be fitted

according to the instructions of the Pferffer commissioning engineer.

5) Sampling socket in the handling equipment collecting dust from cyclone and

separator.

6) Screen for the screening of the feed material (5-150mm screen hole size).

7) Screen for the screening of the finished product (jet stream type screen,

63/90/200 micorons acc. To DIN).

8) Equipment to measure feed moisture and residual moisture.

9) Devices and equipment to weigh the feed material and to calibrate the weigh

belt feeders.

10) Measuring instrument to measure real power or current measuring pliers

(preferably real power measuring instrument).

11) Standard filter’s tools and possibly light –duty tackles.

12) Standard electrician’s tools.

6.3 Commissioning

6.3.1 Commissioning sequence

The commissioning proper can be divided in several steps which are described in

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the following.

1) Essential condition;

The commissioning of the mill may only be started by the engineer in charge of

the commissioning once the assembly of the entire grinding plant is completed. In

addition, the marginal prerequisites mentioned above have to be fulfilled. As it has

been stated in the assembly instructions the entire measuring equipment is to be

connected and all lubrication points provided with oil and grease. The electric

assembly has to be completed, the wiring checked and the power supply ensured.

2) Preliminary adjustment

The mill remains disengaged until shortly before the mill is fed with material.

The preliminary adjustment starts with an inspection of the plant by the

commissioning engineer together with the customer’s chief commissioner and the

engineers responsible for the machine and Electric assembly. The purpose of this

inspection is to familiarize the engineer in charge of the commissioning with the local

conditions within the plant and with the arrangement of the individual machines,

drives and measuring points.

Subsequently the commissioning engineer determines the measuring points from

where the variation of pressure within the plant is to be monitored during the

commissioning by means of U-tube manometers. Corresponding measuring sockets

are to be applied at these points. Furthermore, the position of the measuring sockets

for the gas flow is determined with the help of a pressure head.

The commissioning engineer inspects the mill, i.e. who measures the roller

position and the pressure housing according to the corresponding form

The commissioning engineer checks the oil at all hydraulic units grinding rollers

and the gearbox. All points to be greased with lubricants are checked.

After the completions of these works the individual machines are put into

operation, i.e. the machines are switched on without being interlocked with each other.

The direction of rotation of the drive motors is being checked and the function of the

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machines supervised locally. When commissioning these individual units consult the

operating instructions of the corresponding manufacturer. It is to be ensured that all

fans have to run in fro a certain period of time. During this running-in the bearing

temperatures are to be permanently checked. The hydraulic units are to run in for a

certain period of time, too. Take care that there are no leakages. The unions are to be

retightened, if necessary. Circulate the gearbox oil for the main gearbox oil supply for

some time. Check the filters once and again. Check the claw clutch fro smooth

functioning and set limit switches.

Put tension system in operation by putting pressure on the system, checking the

tightness and by setting the pressure switches. The commissioning engineer

determines the tension pressure at which the mill is to be started. The nitrogen

pressure of the pressure accumulators is to be checked and set. See corresponding

instructions! Set safety valves correspondingly. In any case observe the

commissioning instructions of the manufacturer

Regarding the classifier drive, check the direction of rotation of the classifier

drive motor when the classifier is disengaged. Also check the safety switch at the

manual valve for proper functioning. Fill the piping (pressure pipeline) to go with the

hydraulic motor with oil. Check the zero-position and the final position of the actuator.

Now the unit may be put into operation. Check the speed of the classifier and adjust

the safety valve during the running –up of the classifier. Check the automatic return

movement of the actuator when switching off the motor. In any case the instructions

of the manufacturer have to be observed.

3) Interlocking tests

All machines that have just been operated separately are now to be switched from

the central switch panel in the correct sequence. Check all interlocking conditions

indicated in the interlocking plans. It s to be guaranteed that during these interlocking

tests all pressure switches, flow meters, limit switches etc. have to switch several

times in order to enable the testing of all possible switch conditions within the plant.

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The complete plant is to be run several times under this condition. It is sensible to

have the tests carried out not only by the commissioning engineer but also by the

future operating personnel

These interlocking tests have to be carried out with greatest care. The engineer in

charge of the commissioning has to ensure that all tests are carried out without any

hurry to avoid any mistakes and to guarantee an impeccable operation of the complete

interlocking system. Al defects in the interlocking are to be remedied and the

interlocking has t be checked again. After the completion of these interlocking tests

the plant is heated up several times (by means of the hot gas generator) in order to be

able to check the operation of the plant under normal operating temperature. All units

are to run for several hours. Qualified personal is to permanently supervise the plant

on the spot.

4) Preparation for the commissioning of the plant with material

Before the operation of the mill with material may be stated, a certain initial

material charge has to be brought into the mill. For this purpose the material has to be

filled into the mill feed bins (initially only partly later on more and more) and

conveyed via the transporting equipment to the mill. It is then fed in the area between

air guide cone and housing. This area is to be filled as much as possible. Now the

material has to be filled in the mil centre and in the grinding track. First a layer of

approximately 30-50mm is to be filled onto the grinding track between the grinding

rollers. Then the rollers have to be brought over the material by suing the auxiliary

drive. It is absolutely necessary to take care that during the turning of the track no

personnel stays in the mill and that the reducer oil supply functions perfectly.

By this means a grinding bed of 70 mm is brought onto the grinding track,

depending on the mill size. This grinding bed is meant to prevent the machine from

emptying during the first minutes of the start-up. Now all feed conveyors are to be

emptied via a corresponding chute. Later on they are to be charged again with the

amount of material the commissioning engineer determines for the first start-up. Prior

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to this last filling the calibration of the metering units has to be completed.

5) First start-up of the mill

Prior to the first start-up the plant is to be heated very carefully. Try to quickly

reach a temperature of approximately 100℃ measured downstream of the mill and

keep it for about 1 to 1.5 hours. During this beat-up all units within the grinding plant

have to be in operation and supervised.

Once the plant is heated this way increase the exhaust gas temperature to

approximately 110-120℃ and switch in the mill auxiliary drive. Set the gas volume

downstream of the mill to the gas volume determined by the commissioning engineer.

After the auxiliary drive has been running for the appropriate time (approx. 1 min.,

this is also to be determined by the commissioning engineer) the main drive is

switched on.

The commissioning engineer decides at what time the material feed is to be

started. Usually immediately after switching on the main drive the material feed may

be started in order to prevent an emptying of the mill. During this period all units,

especially the power consumption of the mill man drive, the vibration monitoring and

the mill exhaust gas volume are to be observed. An attempt is to be made at arriving

as quickly as possible at a normal and continuous operation. This includes an increase

in the hot gas volume within a short period of time to meet the heat requirement of the

mill.

The mill is run for a certain period of time with the output determined by the

commissioning engineer (this output is to le approximately 20-30% below the

guaranteed output). Carry out exhaustive measurements within grinding plant during

this period of time. Ensure that the plant is thoroughly supervised on the spot by

competent personnel.

After the mill has been in operation for approximately 50 hours the plant is

meticulously inspected. During this inspection all unions within the grinding plant are

to be checked. The unions of the wear parts at the grinding bowl and grinding rollers

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and the unions of the grinding bowl on the gearbox are tightened to the stipulated

torque. All oil fillings have to be checked. Check grinding rollers and pressure frame.

Measure again grinding rollers and pressure frame.

6) Output test

On the basis of the operating results which have been obtained during the first trial

run the engineer determines the proceedings for the output tests. In these tests the

grinding output is increased to the guaranteed output. Once the guaranteed, output has

been reached. A date convenient to the final customer is agreed upon and the

acceptance test is carried out. Subsequent the acceptance record is signed.

With the acceptance test being carried out the complete plant is once again

meticulously inspected by the commissioning personnel and finally handed over to

the operating personnel.

Leaflet: Commissioning of MLS3424A Grinding Plants

1) Position of grinding rollers

a. Check obliquity

b. Check position of the center

2) Check oil filling of grinding rollers

3) Seal air

a. check direction of rotation of seal air fan

b. check pressures

c. check sea air switch off

4) Tension hydraulics

a. check nitrogen pressure of accumulators

b. check oil level

c. check oil level indicator

d. set limit switch at shut off-valve

e. set four way cock to operating position

f. check direction of rotation of oil pump motor

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g. test pressure of tension hydraulics

h. se t safety –valve

i. check and set minimum and maximum switches

j. set throttle at pressure manometer

5) Mill reducer

a. Control oil level

b. Check immersion heater electrically, if any

c. Set and check minimum and maximum contact at contact thermometer.

d. Switch on oil filter

e. Measure amount of cooling water

f. Vent oil cooler

g. Check direction of rotation of oil pump

h. Check oil flow control instrument for proper functioning

i. Check oil level in segmented thrust bearing

j. Check electric interlocking with main and auxiliary drive

6) Overrunning clutch

a. Check claw clutch for smooth functioning

b. Set stroke

c. Check solenoid valve

d. Set and check master pressure gauge

7) Auxiliary drive

a. Check gearbox oil level

b. Check direction of rotation

c. Observe switching sequence and interlocking auxiliary drive-coupling –main

drive

8) Main drive (individual)

a. Check direction of rotation

b. Trial run with starter

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9) Classifier

a. Check grease filling of classifier bearing

b. Check direction of rotation of driving motor

c. Check direction of rotation of cooling motor

d. Check oil level of planetary reducer

e. Switch unit on

f. Check direction of rotation of classifier

g. Check electric interlocking together with complete plant

10) Set all flaps in the pipeline

11) Mill fan

Put into operation according to instructions of the manufacturer

12) Air valve

Put into operation according to instructions of the manufacturer

13) Turn mill by means of auxiliary drive

a. Check again inclination of rollers

b. Set grinding bed indication

15) MPS vertical roller mills

Tension hydraulics for grinding rollers

The operating pressure of the tension hydraulics is to be in a certain relation to

the nitrogen pre-pressure in order to prevent damages at the rubber bladder of the

nitrogen accumulator. The operating pressure for normal operation is to be limited to:

P=3 x Pst as maximum value

P=1.5 x Pst as minimum value

Pst =nitrogen pressure

P = operating pressure

15) Measurement of grinding roller position

See figure 7

7. Fault clearance, maintenance and lubrication

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7.1 Trouble removing

7.1.1 Mill running roughly

Heavy rumbling (extremely strong vibrations) means imminent danger to the mill

reducer. Therefore the mill has to be shut down immediately. Rough run may be

caused by too little material or by overloading the mill.

7.1.2 Fill level of feed bin too low

In case the mill has to be stopped because of the feed bin containing too little

material there is a danger that the conveyors feeding the mill also run out of material.

In this case these supply units up to the mill feeder must be fed with material without

delay. Otherwise the grinding bed will become thin very fast and the mill will start

rumbling. This might damage the reducer very badly.

7.1.3 Start-up of mill without grinding bed

after repair work or if grinding bed due to lack of material supply was as less as

0-30mm prior to shutdown.

The mill has to be filled with material as follows:

a. Gear oil pump on.

b. Adapt overrunning clutch.

c. Seal air fan on.

d. Auxiliary drive on.

e. Rotary lock or three –flap gate lock on.

f. Switch on supply devices.

7.1.4 Filter outage

In case high dust emission is shown on the indicator, mill output must be reduced

or the mill must be shut down.

7.1.5 Outage of feeding device

In case one feeding device is out of order the grinding plant may still be operated

for a few minutes. However, mill supply by the remaining feeding devices must be

increased to such an extent that the mill does not run out of material.

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In case the supply units from the pre-bin to the mill are out of order the grinding

plant must be switched off before differential pressure and power consumption of mill

motor reach the minimum value.

7.1.6 Outage of mill fan

In case of outage of discharge devices of cyclone or filter the plant has to be

switched off immediately. In no case must the mill be kept running because the

cyclones would be clogged very fast and it is difficult to empty them.

7.1.7 Fine material feeding unsmooth

The mill must be stopped when segregator and filter discharge port break off.

7.1.8 Outage of hot gas supply from kiln

In case the exhaust has fans of the kiln are out of order the grinding plant should

be shut down since otherwise the mill will be overcharged and start rumbling.

7.1.9 Differential pressure too high

Feed to be reduced very much immediately. Watch differential possible causes:

a) Material feed too high due to malfunction of control of feeding devices.

b) Nozzle ring located at the periphery of the grinding bowl is clogged.

c) Air volume in mill too low or inconstant.

d) Setting of classifier much too fine.

7.1.10 Differential pressure too low

Possible causes:

a) Outage of material feed.

b) Wrong indication.

This is the case if the remaining pressure indications ahead and

downstream of the mill are o.k. Mill operation may be continued.

However, feed has to be changed from automation to manual operation.

7.1.11 Tension pressure dropping

Possible causes:

a) Leakage in conduct pipe.

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b) Pressure relief valve out of adjustment.

c) Outage of tension pump.

d) Pressure switch defective.

With an intact plant, operating pressure may be reestablished by switching on

the oil pump. It must be possible to maintain pressure without the pump

being in operation. If not, the mill must be shut down in order to check the

hydraulic system.

7.1.12 Seal air dropping

Check on the machine if pressure remains constant. In that case you needn’t shut

down the mill. The cause of the pressure drop must be eliminated during the next

down-time at the latest. The mill is switched off automatically if pressure drop is such

that the amperage of the fan exceeds a predetermined value due to low

counter-pressure. (This value is set during commissioning and should not be less than

5000Pa.)

7.1.13 The oil pressure or oil flow in reducer min. The mill is switched off

automatically

7.1.14 Bearing temperature in reducer too high

If the bearing temperature exceeds a specific value, malfunction is signaled and

the mill is shut down. Check cooling water.

7.1.15 Material spillage at flap of mill plinth

Possible causes:

a. Mill is overloaded.

b. Air volume in mill is too low.

c. Nozzle ring cove is damaged.

d. Nozzle ring is worn.

Any temporary reduction of the air volume in the mill may also cause material

spillage.

7.2 Maintenance

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7.2.1 Inspection

Regular inspection of all grinding plant avoids unforeseen down-time due to

insufficient maintenance and lubrication. By inspecting the wear parts regularly

replacement can easily be scheduled.

(1) Normal inspection

a. Daily inspection

During operation general inspection of the mill should take place once every

day watching for strange noises and vibrations, loose screws and oil leakage.

Check oil level of hydraulic units every day.

Make sure to also lubricate the classifier bearings, rotary lock and cyclone

discharge locks every day.

b. Weekly inspection

1. Check the sealing of pull rod.

2. Check oil level in reducer and hydraulic station. Watch for oil leakage.

3. Clean seal air filters or replace them if necessary.

4. Check seal air pressure.

(2) Major inspection after long down-time

Some checks are the same as the weekly inspection.

In addition:

a. Check oil level in grinding rollers (once a month).

b. Check fastening of wearing parts on grinding track.

c. Roller tires, grinding track, liner, roller bracket, nozzle ring, housing

walls and any other internals of the mill to be checked for wear.

d. Adjustment of grinding bed indication (necessary with progressing

wear on grinding elements).

e. Check shoe plate of pull rods and sealing.

f. Check all flanges in the mill area for tightness, re-tighten them if

necessary.

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g. All parts in the mill to be checked for wear, especially the seal air

ducts to the grinding rollers.

h. Check all dampers and compensators in the piping for tightness and

movement, respectively and replace them if necessary.

i. Check hydraulic cylinders for leakage and replace sealing element if

necessary.

j. Check plant fan for caking or wear and tear.

k. Check classifier vanes for caking.

7.2.2 Repair work

(1) Disassemble grinding rollers

See installation drawing.

a) Open maintenance doors on the frame.

b) Disassemble the sealing air pipes and temperature measurement on the

grinding roller.

c) Lift the extendible support by means of the conic cover plates, and fix it

by bolts (when assembling, the support is in the conic cover plates).

d) Three sets of supporting bases are mounted on the support by bolts, and

the supporting bases can be turned to the required positions. The height

of supporting bases is determined by the length of the adjustable bolts.

e) Mount six connecting bases on the support of the grinding rollers.

f) The vertical distance between the supporting base and connecting base is

adjusted to about 10mm, and then fixed by the bolts. After these, the

grinding rollers are fastened on the grinding plate by means of wooden

wedges.

g) Dismantle the connecting chain plate between the grinding rollers and the

pressure frame.

h) The pressure housing is lifted up by the tension system, and then is

suspended on the classifier by three pieces of ropes.

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i) After dismantling two connecting bases on the grinding roller, the grinding

roller is lifted up and removed out of the maintenance door by a crane.

j) The second grinding roller and the third grinding roller are, in turn,

removed from the door according to above method.

k) Proceed in reverse order for reassembling.

l) When the mill is remounted, the grinding rollers are mounted into the

housing before the pressure housing and classifier are mounted, so the

assembling tool shall not be needed.

2) Disassembly of grinding plate segments

Once the rollers are dismantled it is very easy to remove the grinding plate

segments. Even with the rollers in place, it is not difficult to replace the segments. In

this case the segments are removed between the rollers and new ones are filled right

away. By turning the mill with the auxiliary drive, it is possible to replace the entire

grinding plate.

Process as follows (rollers being removed):

a) Remove grinding rollers (see above).

b) Remove cover plates of grinding track.

c) Loosen clamp bolts.

d) Remove clamp plates.

e) Dismantle segments.

Start with the inner segment. Since raw material gets pressed between the

segments during grinding, such deposits need to be removed prior to dismantling the

first segment. Moreover, the lateral wedges have to be removed. For ease of removing

the segment, drive in two flat wedges on each side between the segment and the two

adjacent ones to make the gap a bit wider by some lengths of millimeter. Then drive

in another flat wedge between grinding bowl and segment and loosen it.

f) Once all wedges are removed again and the segment is loose, lift it up.

g) If the surface of the grinding bowl turns out to be uneven, smooth it by means

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of an electric hand grinding machine. To improve the seal of the segments,

appropriate metal putty or any similar material may be spread underneath.

h) Before installing the new segments, check if the edges of the contact surfaces

of the two cast noses are rounded or beveled so that they do not press onto the contact

surface of the grinding track.

i) When mounting the segments, ensure to fit of the two cast noses tightly on the

contact surface (outer edge of grinding bowl) and for proper seal of segment on the

grinding track surface. Check by means of a feeler gauge. On the outer edge of the

grinding track, 0.05 mm are allowed between the noses and contact surface, whereas

the clearance between the segment base and the grinding track surface must not

exceed 0.1 mm. In case these values are exceeded, the segment is required to be

ground by means of a hand grinding machine. As already stated above, the seat of the

segment on the grinding track surface may be improved by means of appropriate

metal putty.

j) Once three segments each are in place, fix them by clamp plates.

k) Tighten clamp bolts (T-head bolts) with torque wrench. Observe torque

indicated on drawing.

l) Also, place wedges between each segment and the two adjacent ones.

m) Make sure to provide for proper seating of the segments both on the outer edge

of the grinding track and on its surface. If required the noses have to be machined as

described under g) above.

3) Replacement of grinding roller bearing and grinding roller sealing

The bearings used in the grinding rollers are such that extremely long lifetime can

be achieved. However, it may nonetheless be necessary as is the case with any

mechanically moveable parts to replace the bearings. In the following the various

steps as to how to replace the bearings and sealing are described. For this purpose, the

grinding rollers have to be removed as described above.

a) Disassembly of bearing



Once the two bearing covers are removed two connections on the bearing housing

are exposed. Through these holes, oil can be pumped by means of a hydraulic hand

pump in between the outer rings of the bearing and hearing housing allowing for the

bearing to be removed.

b) Fitting of bearing and sealing

1. Fasten bearing cover on housing without using the O ring or radial shaft

sealing rings.

2. Heat up bearing housing and bearing cover to about 110℃.

3. Push outer ring of cylindrical roller bearing into housing until it rests against

bearing cover.

4. Distance ring to be pressed into bearing housing until it rests against the outer

ring of the cylindrical roller bearing.

5. Self aligning roller bearing to be pressed into bearing housing.

6. Inner ring of cylindrical roller bearing to be heated in oil bath up to about

120℃ and then pulled onto shaft.

7. Remove bearing cover as soon as bearing housing has cooled down to ambient

temperature.

8. Inner distance ring to be put into housing so that it rests against the

self-aligning roller bearing.

9. Shaft to be pressed carefully into housing until inner ring of cylindrical roller

bearing rests against inner distance ring.

10. Mount locking washer.

11. Mount sealing rings into bearing cover.

12. Mount bearing cover by means of mounting ring.

13. Remove mounting ring.

14. Assemble grinding roller and pressure bracket.

15. Mount grinding roller into mill.

Grease and oil the rollers according to instructions (see lubricant chart) prior to

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putting the mill back into operation.

(4) Replacement of grinding roller segments

For replacing worn-out roller segments, if they are worn mostly on one side, for

turning them around on the roller body, it is recommended to remove the roller from

the mill. For ease of removing and refitting the segments, a tilting arrangement may

be fitted on the inner wall of the mill housing allowing for the segments to be

removed from the mill and new ones to be refitted by means of a tackle suspended

from a crawl ( sort of wall mounted tilting crane).

One roller has twelve segments. Three of them are partly covered by the pressure

yoke whereas the three opposite ones are facing the grinding plate. So start with the

three segments on the right side or left side of the roller. After having removed at least

two of three segments on one side, the new one will be fitted. Then turn the roller on

the grinding plate with the auxiliary drive so that another segment can be replaced.

Since the roller turns anticlockwise, the second segment to be replaced is either

that following the first one top right which has been fitted before on the roller body or

that following the first one bottom left fitted before depending on whether you start

working on the right side or left side of the roller.

Procedure for replacing or turning the segments is as follows:

a) Loosen clamp bolts.

b) Remove clamp plates.

c) Lift off segments and take them out of the mill.

d) Clean contact surface and check it for unevenness.

e) In case the contact surface on the roller body is not smooth, use metal putty to

improve the seat of the segments or weld the contact surface. But make sure

not to cause any torsion of the roller body as a result of heating it up too much

during welding. It is also recommended to dismantle the bearings and sealing

from the roller prior to welding.

f) Mount new segment or turn the old one around 180 degree. Make sure that



the edge of the contact surface of the segment is rounded so as to avoid any

concentrated force on the roller body.

g) When laying the segments, ensure for proper sealing of the lateral contact

surfaces and base surface. Check by means of a feeler gauge. On the lateral

contact surfaces, a 0.05mm clearance between the contact surface of the

segment and that of the roller body is allowable, whereas the clearance

between base surface of segment and roller body must not exceed 0.1mm. if

these values are exceeded, the segment needs to be ground with a hand

grinding machine As already described under e) above, the seat of the

segments on the roller body may be improved by using metal putty if

mechanical machining can’t be done.

h) Segment to be pressed tight onto roller body by means of a special pressing

device or hydraulic pump. Pressing must be maintained until clamp plates are

fixed and clamp bolts are tightened with a torque wrench.

i) Fix clamp plates

j) Tighten clamp bolts with torque wrench. (Torque to be observed is indicated

on drawing of grinding roller.)

k) The segments are provided with cast noses. If new segments are mounted,

these noses might have to be ground.

l) We wish to point out once again that proper seating of the lateral contact

surfaces and base surface is imperative without exceeding the tolerances

indicated above. If required the lateral contact surfaces are to be machined as

described under g) above.

7.2.3 Disassembly and assembly the reducer in mill

In case there is damage at the reducer of mill making it necessary to remove the

gear, this can be pulled out form below the mill without dismantling the latter. The

grinding parts can be left in the mill. For any work to be carried out on the gear itself,

the relevant manufacturer’s instructions are applicable.

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(1) The following preparations are required for removing the gear below the mill:

(a) Pump oil out of reducer. Follow gear manufacturer’s instructions.

(b) For safety reasons, all electric switches in the plant are to be off and secured

(most suitably by padlock). Remove fuses for auxiliary drive, main drive and oil

pump form fuse box in the central control room. Cut off all drives from power supply.

c) Once the oil has been pumped out of the reducer, remove all thermometers,

thermocouples and manometers which hinder the removing of the gear.

d) Remove coupling protection and any other protective arrangements. Also

disengage compressed air line from claw coupling, if any, and any other piping that

are hindering.

e) Disengage all electric feed lines of all motors that are to be removed, i.e.

auxiliary drive and main drive of mill. Don’t forget to mark the different cables to

reconnect them correctly later on.

f) Remove auxiliary drive complete with supporting stand as well as mill main

drive with motor support. In case, for ease of alignment, shims had been placed under

these supporting structures, these must be marked to facilitate reinstallation when the

parts are remounted later on.

g) Start removing the reducer now.

(2) Removal of reducer below the mill

As already stated, for this purpose, the mill is not required to be disassembled

nor do the grinding parts have to be removed Proceed as follows:

a) Unscrew and remove from below the three covers provided in the bottom of the

mill base.

b) If it is possible to turn the grinding bowl placed on top of the gear, check as to

whether the three detachable insulating plates provided on the grinding bowl are

right above the three openings uncovered in the bottom of the mill base. The

grinding bowl insulation is detachable in these three places because later on when

mounting the supporting irons between the hydraulic pumps and grinding bowl for

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pushing up the latter, the insulation would otherwise be damaged. So, if required,

turn the grinding bowl so as to bring the detachable insulating plates right above

the openings in the bottom of the mill base. If it is no longer possible to turn the

grinding bowl, the entire insulation has to be dismantled. In case one of the

scrapers happens to be above one of the three openings, this scraper has to be

unscrewed or, if this is still possible, turned on. To carry out a.m. works, go inside

the mill base through the entrance hatch next to the gas intake channel.

c) Once steps 1 through 6 described under I. Above are completed, remove the cover

in the center of the grinding bowl. For this purpose, remove the screws of the

cover. Of course, any material that might be on the grinding track has to be

removed as well.

d) Remove the screws connecting the grinding bowl to the reducer output flange.

There is, however, no need to remove the two pins.

e) Fit supporting irons for pushing up the grinding bowl.

f) Prior to setting up the three hydraulic hoisting jacks for pushing up the grinding

bowl, lay a girder across the leakage oil receptacle in the rear of the reducer to put

one of the hoisting jacks on it. The girder has to be designed so as to avoid that the

lid of the oil receptacle breaks due to the weight of the pump.

g) Set up the three hydraulic jacks.

h) If at this stage there are no supporting irons available, these have to be fabricated.

For this purpose, use thick walled pipes, cut them as required for each hoisting

jack, and, for better seating, weld a square plate onto their upper and lower ends.

If pipes are not available, use iron of I-section or channel design instead. When

preparing these supporting irons, it has to be taken into account that the entire

weight of the grinding track including grinding plate, three grinding rollers plus

pressure housing with pull rods has to be pushed up. The grinding bowl, in

addition, may sit tight on the output flange.

i) The supporting irons will then be placed between the three hoisting jacks and the



grinding track. They must exactly be vertical pressing uniformly onto the hoisting

jack and the underside of the grinding track.

j) Before pushing up the grinding track upwards, the operating load of the tension

system has to be fully released by means of the relief valve of the tension pump.

The valve must remain open. Of course, the tension pump will be off.

k) Now push up the grinding track uniformly by means of the three hoisting jacks and

supporting irons until the grinding track clears the output flange. If the carrier bolts

are still in the grinding track, these have to clear the output flange as well. Before

pushing, mark the grinding track and output flange so as to replace it later on into

the same position of pins and bolts.

l) Once the grinding track is pushed up don’t let the pumps and grinding track go

down. Pumps and supporting irons are to be secured.

m) Remove bolts and pins from reducer foot.

n) The reducer will now be pulled out by means of rope winches or cranes with

pulleys. If the reducer doesn’t move at first, lift it a bit by means of a pump or

winch to loosen it from the reducer plate. For ease of sliding, the skids may be oiled

or greased or the entire reducer may be put onto steel shafts.

(3) Refitting the reducer

Proceed in reverse order.

a) First of all properly clean the contact surfaces of reducer foot and

reducer plate.

b) Pull the reducer back inside the mill base by means of the rope winches.

Make sure to bring the holes for the pins in the reducer foot right above those

in the reducer plate because otherwise the pins cannot be driven in.

c) Drive in pins and bolts. The bolts need not be tightened that much.

Similarly, just drive in the pins with some slight hammer blows.

d) Remove the securing devices keeping the grinding bowl from going

down.

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e) Make sure that the markings provided on the output flange and grinding

track coincide by turning the output flange accordingly.

f) Clean contact surfaces of output flange and grinding track.

g) Put the grinding track back onto the reducer by uniformly releasing the

pressure on the three hydraulic hoisting jacks. Make sure that the pins fit

properly into the holes and provide for snug fit of the grinding track and

output flange. Do not tilt the grinding track because the contact surfaces might

be damaged.

h) Remove hydraulic hoisting jacks and supporting irons.

i) Drive in screws to fasten the grinding track on the output flange and

tighten them.

j) Re-establish operating load of tension system by means of tension pump.

k) Use 0.1 mm feeler gauge to check as to whether the grinding bowl sits

tight all over its underside on the output flange. Retighten screws if required.

l) Once proper seat is achieved, refit the cover in the center of the grinding

track.

m) Remove hoisting jacks and girder across leakage oil receptacle.

n) Close the three covers in the bottom of the mill base and refit detachable

insulating plates.

o) In case all of the insulation had to be removed, refit it now. Also refit the

scraper if this had been removed.

p) Screw piping back onto the gear. Don’t forget the sealing.

q) Tighten screws on gearbox foot. Observe toque specified. Drive in pins with

hammer blows.

(4) Completion

a) Once the reducer is back in place, the mill main motor with supporting structure

will be mounted. After having aligned it properly, proceed to align the auxiliary

drive with supporting structure. The mill main motor needs to be realigned very

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precisely. The motor shaft has to be perfectly in line with the gear shaft. Using a

flexible coupling does not render it superfluous to provide for exact alignment.

Also, the pins must be driven into their original holes.

Once these steps are completed, the auxiliary drive will be installed; it has to be

aligned as well to avoid any premature wear affecting only one side of the coupling.

Check screws for tight fit.

b) Connect all electric feed lines to the motors. Watch out for correct connection of the

various phases to the terminal boxes. (This is why marking has to be provided when

disengaging tem) the mill main motor has to be connected such that it turns in the

direction marked by arrow on the reducer. Similarly, ensure for proper sense of

rotation of auxiliary drive which will function in one direction only.

c) Connect oil piping and compressed air piping to claw coupling (if any). Don’t forget

the sealing d) Refit all thermometers, thermocouples, and manometers. Don’t forget

the sealing.

e) Mount coupling protection and any other protective arrangements.

f) Get oil pump motor (to be wired) as well as oil pump with piping and filter cooler

(refit all units required) ready for operation.

g) Refit oil into reducer according to manufacturer’s instructions.

h) Refit all electric fuses, connect ammeter, turning switches to “ON”. The plant can

now be brought back operation in systems.

7.3 Lubrication of mill

7.3.1 Lubrication of mill reducer (See the manufactory’s specification)

The mill reducer is lubricated by special lubrication oil station.

The reducer is equipped with hydro-static lubrication system. All the twelve thrust

bearing are equipped with hydro-static lubrication pipes and the gears is lubricated by

means of oil spraying.

The thrust bearing is immersed in oil pool. The oil level is above the working

surface and stable. The fresh oil is sprayed in through the ring-shaped nozzle in order to

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cool the thrust bearing.

a. Oil filling

Fill in the industrial gear oil (ISOVG220) through the inspection hole to specified

mark. Start the oil pump to fill the pipes full of oil. Shut down the pump and refill oil to

the specified mark. In case the ambient temperature is below zero or long period of

shutdown, we recommend to putting the oil pump into operation for several hours

before putting the gearbox into operation.

b. Shutdown

When the mill is shut down in normal condition, it will take the grinding plate a

certain length of time before the grinding plate stops. The lubrication of gearbox must

be ensured by delay relay during the idling running. In short time of shutdown, the high

pressure pump stops working and low pressure pump continues to work to ensure that

the mill can be started at any time.

c. Oil replacement

Replace oil for the first time after the running of gearbox about 2000 hours.

Replacing of oil depends on the quality of oil. The oil should be periodically checked

and normally replaced once every 5000 –10000 hours.

d. Oil discharge

Open the cover of inspection hole and discharge oil with the cleaning pump. The

remained oil can be discharge from the bleeding plug on the reducer case.

7.3.2 Lubrication of grinding roller bearing

The grinding rollers whose bearing is lubricated by oil pool with the ball bearing

immersed in the oil pool are very important parts of the mill. Since the rollers are in

inclination state during operation, one side of bearing is completely immersed in oil.

Oil can be easily introduced into the roller bearing on the pressure frame side through

the oil guiding vanes.

a. Oil filling

The oil is filled into the grinding roller bearing through the oil hold on the cover

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of roller bearing to specified oil level (see lubrication chart for oil brand), and the oil

should be replaced periodically. For the first time of oil filling, two of the three oil

filling holes should be placed horizontally. Open the two plugs one for filling oil, one

for bleeding air. Re-fix the plugs after the oil reaches the hole.

The sealing parts on the cover of grinding roller bearings are periodically

lubricated by grease contained in a special cup.

b. Oil replacement

The first time of oil change shall be carried out in about 1000 hours running of

rollers. Oil replacement depends on the quality of oil. It will be much better to

check the quality of oil once every two months.

c. Oil discharge

Rotate the grinding roller via auxiliary drive so that the oil filling hole is in the

lowest position, and then open the plug to discharge oil.

7.3.3 See lubrication chart for the other lubrication points

The following recommended lubricating oil (grease) is only for the customer’s

reference, the customer can also select oil (grease) according to his own condition.

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Lubricating oil list

Lubrication oil brand No. Lubrication point Condition

International China

1 Reducer Lubricated by oil ISOVG220

ISOVG320

SP type N-220limit pressure industrial

gear oil (LPIGO)

SP type N-320 LPIGO

Exhaust gas temperature

40-60℃

ISOVG150 SP type N-150 LPIGO

55-75℃ ISOVG320 SP type N-320 LPIGO

70-90℃ ISOVG680 SP type N-680 LPIGO

2 Grinding roller

85-120℃ viscosity

90cSt/100℃

V1=200

Specially made high temperature grinding roller oil(synthetic lubricant)

low temp. area ISOVG22 N-22wear-resistant hydraulic oil

(WRHO)

medium temp. area ISOVG46 N-46 WRHO

3 Tension device hydraulic system

high temp. area ISOVG68 N-46 WRHO

4 Auxiliary gearbox of classifier planetary gearbox Lubricated by oil ISOVG2220 SP type N-220 LPIGO

5 Fan bearing Lubricated by grease K3K ZL-3 Lithium-based lubrication grease

(LBLG)

6 Classifier bearing Lubricated by grease KPF2K ZL-2 LBLG

7 Grinding roller seal

bearing Lubricated by grease K3K ZL-3 LBLG

CHINA

Lubricated by oil ISOVG68 N-68 WRHO 8

Other lubrication points

Lubricated by grease K3K ZL-3 LBLG CHINA

Note: The adoption of synthetic lubricant can prolong the operation period. The

synthetic lubricant has the following advantages:

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1. Good properties in both high and low temperature.

2. Good lubricating property.

3. Good chemical invariability

4. Good fire resistant property.

Be recommend to use oils supplied by Shenyang Special Type Oil Chymist

Product, China.

5. It should be did justice to the lubricant of exhaust gas, in order to

avoid the environmental pollution.

8．List of rolling bearing

List of rolling bearing

Belonging to drawing No. Code of bearing Name and specification Total

Indent number Amount Remark

1 23180CA

spherical roller bearing

400×650×200 3 SP2283.09.00 1

2 NNU4180 cylindrical roller bearing

400×650×250 3 SP2283.09.00 1

3 22238CC/W33 Adjusting center roller

bearing 190×340×92

1 SP2283.01.00 1

4 24140CC/W33 Adjusting center roller

bearing 200×340×140

1 SP2283.01.00 1

5 29340 Thrust centripetal roller

bearing 200×340×85

1 SP2283.01.00 1

6 GE140ES outer inner ring of spherical

plain bearing 140×210×90

3 SP2283.08.00 1 CHINA

7 GE140ES outer inner ring of spherical

plain bearing 140×210×90

3 SP2283.08.00 1

Without lube

notch(CHINA)

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9． List of wearing parts

List of wearing parts

Drawing No. Designation Material Belonging to drawing

No.

SP2283.01.02.16 Liner Ⅰ DILLDUR400V SP2283.01.00

SP2283.01.02.17 Liner Ⅱ DILLDUR400V SP2283.01.00

SP2283.01.02.18 Liner Ⅲ DILLDUR400V SP2283.01.00

SP2215.3.380 Guard plate Assembly part SP2283.03.00

SP2283.09.05 Grinding roller Liner Ni-cast iron 4 SP2283.09.00

SP2283.09.13 Clamping plate ZG270-500 SP2283.09.00

SP2215.9.40 Liner Special part SP2283.09.00

SP2283.09.040 Doubling plate Welding part SP2283.09.00



SP2283.10.040 Air guide cone SP2283.10.00

SP2204.4.7 Grinding track liner Ⅰ Ni-cast iron 4 SP2283.10.00

SP2204.4.9 Grinding track liner Ⅱ Ni-cast iron 4 SP2283.10.00

SP2283.10.030 Nozzle ring liner Welding part SP2283.10.00

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10.The schematic diagram of hydraulic and pneumatic system.

10.1 Fig.2 Drawing of Tension Device Hydraulic System.

10.2 Fig.3 Air pipeline drawing of Overrunning clutch.



Fig.3

10.3 Fig.4 Drawing of Grinding roller assembling and checking device Hydraulic

System.

Fig.4

10.4 Fig 5 Drawing of Three-flap Gate Hydraulic System.

Documents

RAW MILL VERTICAL ROLLER MILL.pdf