Abstract)…………………………………………………………………………… 2

HIT products)……………………………………………………………………… 4

Shop-2)……………………………………………………………………………...5

Shop-k………………………………………………….,……………………….. 11

Shop-6……………………………………………………………………………. .16

Shop-8………………………………………………………………………. …… 19

Shop-12…………………………………………………………………………….23

Shop-10&14………………………………………………………………………..26

Shop-16,17…………………………………………………………………………30

Shop-4………………………………………………………………………………35

QC(D)………………………………………………………………………………39

EM Br)……………………………………………………………………………...40

CNC Control Room)………………………………………………………………..41

References………………………………………………………………………….44

document.doc

Abstract

Heavy Industries Taxila (HIT) is a large defence equipment production industry of Pakistan.

it is reputed mainly because it is a main one and only tank manufacturing industry of

Pakistan . Machining covers several processes .DESCOM undertakes manufacture of

components, assemblies, tools, dies, gauges and arranges development of spare

parts .there are no. of shops which are also equipped with CNC s and skilled labour.this

factory is also equipped with EM branch as well as Quality Control branch. main

products it provides our country are tanks ,APC,ARV and Guns. and further progress is

expected.

Heavy Industries Taxila 2

Heavy Industries Taxila (HIT), employing over 7000 workers, is a manufacturing facility

which has built the MBT 2000 "Al-Khalid", APC M-113, IFV Al-Zarar fighting vehicles

for the Pakistan Army. In 1971, a Heavy Rebuild Foundry Project (P-711) was conceived

with Chinese assistance and technology to rebuild T-59 tanks. As the fleet of T-59

manufactured by China grew, Heavy Rebuild Factory (HRF) was established in Taxila in

the late seventies to undertake rebuild and modernization of tanks. The experience

acquired in enhancing firepower, mobility and protection significantly enhanced the

capabilities of HRF, which subsequently grew into a multi-factory environment renamed

heavy Industries Taxila (HIT) in September 1992. Activities now include the cost

effective manufacture of armoured fighting vehicles, armored personnel carriers and tank

guns. In addition, in-house manufacture of a large array of components required has been

undertaken and an infrastructure built for interacting with the indigenous industry for

development of materials and components required.

Heavy Industries Taxila 3

HIT PRODUCTS

Heavy Industries Taxila (HIT) is a large defence equipment production industry comprising

six major production units and engineering support facilities.

The industry is under taking following activities:-

a. Rebuilding, up-gradation and modernization of tracked vehicles.

b. Manufacturing of tanks, Armoured Personnel Carriers and its variants,

Armoured Recovery Vehicles, tank guns and security vehicles.

Tank Al-khalid

Tank Al-Zarar

Tank T-85IIAP

Tank T-69IIMP

Tank T-59MII

ARV W653

APC M113

APC Talha

Security vehicle Mohafiz

APC Saad

APC Hamza

Command post carrier Sakb

Logistic vehicle Al-Qaswa

APC Al-Hadeed

Armored guard post Ahan(one

man)

Armored guard post Ahan(two

man)

SP-Gun M-109

APC Maz

APC Mauz

Cash caring vehicles (Neghban)

Development, Engineering Support and Components

Manufacture (DESCOM)

This production facility has been established to provide engineering support to all the

factories of HIT. Equipped with CNC machines, it undertakes manufacture of

components, assemblies, tools, dies, gauges and arranges development of spare parts

through the vendor industry. It also provides repair and maintenance support to

machinery and equipment installed in HIT.

Heavy Industries Taxila 4

SHOP-2

AWM Farhan Ali

MANUFACTURING AND MACHINING PROCESS

Machining is the broad term used to describe removal of material from a workpiece; it

covers several processes, which we usually divide into the following categories:

Cutting, generally involving single-point or multipoint cutting tools, each with a

clearly defined geometry.

Abrasive processes, such as grinding.

Nontraditional machining processes, utilizing electrical, chemical, and optimal

sources of energy.

Main machines which are being used in shop-2 are as fellows:

Lathe

A lathe is a machine tool which spins a block of material to perform various operations

such as cutting, sanding, knurling, drilling, or deformation with tools that are applied to

the workpiece to create an object which has symmetry about an axis of rotation.

metal is removed from the workpiece using a hardened cutting tool, which is usually

fixed to a solid moveable mounting, either a toolpost or a turret.The workpiece may be

supported between a pair of points called centres, or it may be bolted to a faceplate or

held in a chuck. A chuck has movable jaws that can grip the workpiece securely.

All lathes have a bed, which is (almost always) a horizontal beam. At one end of the bed

(almost always the left, as the operator faces the lathe) is a headstock. The headstock

contains high-precision spinning bearings. Rotating within the bearings is a horizontal

axle, with an axis parallel to the bed, called the spindle. The counterpoint to the

headstock is the tailstock, sometimes referred to as the loose head, as it can be positioned

Heavy Industries Taxila 5

at any convenient point on the bed, by undoing a locking nut, sliding it to the required

area, and then relocking it. Metalworking lathes have a carriage (comprising a saddle

and apron) topped with a cross-slide, which is a flat piece that sits crosswise on the bed,

and can be cranked at right angles to the bed. Sitting atop the cross slide is a toolpost,

which holds a cutting tool which removes material from the workpiece.

Feed, Speed, and Depth of Cut

Cutting speed is defined as the speed at which the work moves with respect to the tool

(usually measured in feet per minute). Feed rate is defined as the distance the tool travels

during one revolution of the part. Cutting speed and feed determines the surface finish,

power requirements, and material removal rate. The primary factor in choosing feed and

speed is the material to be cut. However, one should also consider material of the tool,

rigidity of the workpiece, size and condition of the lathe, and depth of cut.To calculate

the proper spindle speed, divide the desired cutting speed by the circumference of the

Heavy Industries Taxila 6

work. Experiment with feed rates to achieve the desired finish. In considering depth of

cut, it's important to remember that for each thousandth depth of cut, the work diameter is

reduced by two thousandths.

There are 3 Vertical lathes in this shope, which are commonly used for machining of

sprocket.

Drilling machine

Drill: Drill can be defined as a rotary end cutting tool having one or more cutting lips,

and having one or more helical or straight flutes for the passage of chips and the

admission of a cutting fluid

Heavy Industries Taxila 7

Gear manufacturing

Gear Basics

Gears are used to reverse rotational direction, increase or decrease speed of rotation,

transfer rotation to a different axis, or to synchronize rotation across two or more axis in a

machine or engine. The basic gear train is comprised of two gears, one large and one

small. They rotate in opposite directions from one another, with their teeth interlocking

and driving the rotation. A gear in a train is referred to as a driver (the gear that effects

the rotation), a driven gear (the gear last in the train), or an idler (any gear between the

first and last gear). The power output or torque produced by a gear train is determined by

the gear ratios and the by output direction (which gear drives which).

Gear Types

Spur Gear: characterized by their straight cogs, these gears are mounted on

parallel shafts. You'll find examples of spur gear trains in watches and clocks.

Bevel Gear: characterized by cogs cut in a cone shape. The gear shafts are

generally mounted at 90º angles to each other.

Worm Gear and Wheel: a gear comprised of a wheel gear with inclined cogs that

is rotated by a screw thread (a single-cogged gear called a worm).

Helical Gear: characterized by cogs that are cut at an angle to the face of the gear.

Can be mounted perpendicularly or parallel. Automobile transmissions make use

of these gears.

Manufacturing

Hobbing

Heavy Industries Taxila 8

Hobbing is a machining process for making gears, splines, and sprockets on a hobbing

machine, which is a special type of milling machine. The teeth or splines are

progressively cut into the workpiece by a series of cuts made by a cutting tool called a

hob. Compared to other gear forming processes it is relatively inexpensive but still quite

accurate, thus it is used for a broad range of parts and quantities such as cylinder of tank

engine

Honing machine

Honing is a manufacturing process that produces a precision surface on a workpiece by

scrubbing an abrasive stone against it along a controlled path. Honing is primarily used to

improve the geometric form of a surface, but may also improve surface texture.

honing is a relatively expensive manufacturing process. The improved shape after honing

may result in a quieter running or higher precision component.

Thread rolling machine

This type of cold-forming process is used because cylindrical parts (such as the

remaining round part of the bolt) can easily have thread applied by rolling the work billet

through two dies. The thread rolling process is usually chosen over machining because

thread rolling provides higher production rates, more effective material usage, stronger

thread due to work hardening, and finally better fatigue resistance because the work billet

undergoes compressive stresses during the rolling process.

Heavy Industries Taxila 9

CNC LATHE MACHINE SHOP

The machine is controlled electronically via a computer menu style interface, the

program may be modified and displayed at the machine, along with a simulated view of

the process.

Specifications of E45 CNC lathe

Working range

Swing over bed ………. φ430

Max. turnig dia …………. φ 220

Max turning length …….. 310

Travels

x………160

z………310

main spindle –clamping system

max size of chuck……. φ 160

tool system

revolve type tool turret iwith direct logic option with driven tool

toolin g fixture acc to DIN 69880

Suggestions

DON’T work with OILY or GREASY hands.

Handle SHARP-EDGED and POINTED TOOLS with care.

DON’T use screwdrivers as chisels or pry bars.

Wear the RIGHT SAFETY EQUIPMENT for the job.

Use tools that are the RIGHT SIZE & RIGHT TYPE for your job.

Follow the correct procedure for using EVERY tool.

Keep your cutting tools SHARP and in good condition.

Heavy Industries Taxila 10

SHOP –K

WM Qamar uz Zaman

MANUFACTURING AND MACHINING PROCESS

Main machines in this shop are:

Lathe m/c =38

Grinder m/c =26

Drilling m/c =16

Milling m/c =30

Boring and reaming m/cs =08

Cranes =04

Total m/cs =172

Milling machine

Milling machine is a machine tool used for the

shaping of metal and other solid materials.

Milling machines exist in two basic forms:

horizontal and vertical, which terms refer to the

orientation of the cutting tool spindle. milling

also involves movement of the workpiece against

the rotating cutter, the latter which is able to cut

on its flanks as well as its tip. Milling machines

can perform a vast number of operations, some

very complex, such as slot and keyway cutting,

planing, drilling, die sinking, rebating, routing,

etc. Cutting fluid is often pumped to the cutting

site to cool and lubricate the cut, and to sluice

away the resulting swarf.

Heavy Industries Taxila 11

Grinding Machine

Value of Grinding as Finishing Process. When greater accuracy than that obtainable on

the milling machine or the lathe is required, recourse is had to grinding. This operation

depends upon the abrasive or cutting qualities of emery, corundum, and carborundum.

With work properly held to a solid grinding wheel, it is not difficult to attain great

accuracy. By means of the grinding machine, parts may be economically finished, even in

hardened steel that could not possibly be machined on such shop tools as the lathe,

planer, or shaper.

Features of Grinding

Process.

The headstock and tailstock are

mounted upon a traveling table ,

which moves back and forth in

the same manner as the platen of

a planer. It is made to stop

automatically at each end of the

stroke.

A coarse wheel grinds faster than

a fine one, but leaves deep

scratches in the work. A soft

wheel may be made of a much finer grade than a hard one.

A soft wheel grinds faster than a hard one, but it is apt to glaze over, or fill up with

particles, if used on a soft material.

Broaching

is a machining operation which uses a toothed tool, called a broach, to remove material.

The broach is used in a broaching machine, which is also sometimes shortened to broach.

It is used when precision machining is required, especially for odd shapes. Broaching

Heavy Industries Taxila 12

finishes a surface in a single pass, which makes it very efficient. Commonly machined

surfaces include circular and non-circular holes, splines, and flat surfaces.

Process

Internal broaching is more involved.

The process begins by either clamping

the workpiece into workholder of the

broaching machine or the workpiece is

placed on a spherical workholder

designed to automatically align the

workpiece to the broach. The elevator

of the broaching machine then lowers

the pilot of the broach through

workpiece where the puller engages

broach pilot. The elevator then releases the top of the pilot and the puller pulls the broach

through the workpiece completely. The workpiece is then removed from the machine and

the broach is raised back up to reengage with the elevator.

Horizontal Boring Machine

A horizontal boring machine or horizontal boring mill is a machine tool which bores

holes in a horizontal direction. There are three main types — table, planer and floor. The

table type is the most common and, as it is the most versatile, it is also known as the

universal type. A horizontal boring machine has its work spindle parallel to the ground

and work table. Horizontal boring machines are often heavy-duty industrial machines

used for roughing out large components but there are high-precision models too.

Heavy Industries Taxila 13

SPECIFICATIONS OF CNC MILLING

Automatic machines are generally used to minimize the need for manual effort.   The

benefits are reduced operating costs, reduced operator errors, increased reliability,

minimum work reduction due to human fatigue, illness and labor disputes.

Make= Ferrari

Type= A17

Country of origin =Italy

CNC control =E520

Computers]

Built in machine 80486-100MHZ

Separate PC (can be interfaced )=80486-66MHZ with machine through cable

Software

ELEXA =For CNC processing

DAM= for design and manufacturing of complex parts

Table size

1250 x560 mm

Spindle

Speed (max) =5000 RPM

Rated power of motor = 10KW

Travels

X-axis longitudinal (1050mm)

Y-axis transverse (520)

z –axis vertical (420)

C-axis tilting of milling head (+,-90°)

A –axis CNC dividing head (360°)

Accuracy = .001

Tool magazine capacity =19

Sp-2 =.01

Heavy Industries Taxila 14

For 3-D digitizing (tracing)

MP7

For determining of w/p origin

For measurement of jobs

Suggestions

DON’T work with OILY or GREASY hands.

Handle SHARP-EDGED and POINTED TOOLS with care.

DON’T use screwdrivers as chisels or pry bars.

Wear the RIGHT SAFETY EQUIPMENT for the job.

Use tools that are the RIGHT SIZE & RIGHT TYPE for your job.

Follow the correct procedure for using EVERY tool.

Keep cutting tools SHARP and in good condition

Heavy Industries Taxila 15

SHOP-6

AWM Shuja-ud-Din

SURFACE TREATMENT

Surface Treatment is used to describe a number of industrial processes that can be

applied to improve the surface of a manufactured item. The major reason to apply these

processes is to improve appearance, improve adhesion or ink wet ability, corrosion

protection, wear resistance and friction control also are areas where performance can be

enhanced by these treatments.

Machinery Equipment and Process Of Surface Treatment

(East hall)

Zinc plating

● No. of plating tanks=4

● ZnO, sodium cyanide, NaOH

● Degreasing, pickling, plating, passivation

● Corrision resistence

● clamps, spring, tarsion bar, pipe etc

● Time 20-30 min Temperature 100C

Cadmium plating

Heavy Industries Taxila 16

● No. of plating tanks=01

● Cdmium sulphate, sodium cyanide, soduim hydroxide

● Degreasing, pickling, plating, passivation

● Prevention from rust and seepage

● Time= 1-1.5 hr Temp= 1200C

Copper plating

● No of plating tanks= 02

● Copper cyanide, sodium cyanide

● Degreasing, pickling, plating, passivation

● Prevention from carbonizing and rust

● Gas, shafts, nuts

● Time=1.5-2 hrs Temp=10-30C

Tin plating

● No. of plating tanks=01

● Sodium stanate, NaOH, sodium acitate

● Degreasing, pickling, plating, passivation

● Solder ability and prevention from nitriding

● Cylinder liner, thimble, connector

● Time=40-50 min Temp= 70-85C

Aluminum anodizing

Heavy Industries Taxila 17

●No. of plating tanks= 01

● Sulphuric acid

● Bright, oxidation, color

● Surface hardness, color of aluminum components

● Telescope body

● Time=20-30 min Temp= not above 25C

Copper oxidation

● No of plating tanks=01

● Potassium pursulphate, sodium hydroxide

● Degreasing, pickling, plating, plating, oxidation

● Prevention from reflector

● Screw, washer, nut

● Time-5-10 min Temp=60-70C

(West hall)

Chrome plating

● No of plating tanks=06

● Chromic acid, sulphuric acid

● Degreasing, pickling, plating

● Reclamation of undesired components

Heavy Industries Taxila 18

● Gudegon pins, shafts, bearing, seats etc

● Time= .15-10 hrs Temp=55-60C

Nickel plating

● No of plating tanks=01

● Nickel sulphate, magnesium sulphate

● Polish, degrease, plating ● Reflection and decoration

SHOP-8

AWM Shoukat Ali

Heat Treatment

Various heat treatment processes are used to change the properties or conditions of

material.

Importance of heat treatment of steel

Increase the hardness

Improve the toughness

Increase the ductility

Improve the machinability

Refine the grain structure

Remove the residual stresses

Heavy Industries Taxila 19

Improve the wear resistance

Machines used in this shop are given with their specifications

process /oprations max capabilities

anealing Φ550x1000 mm

normalizing 550X1000 mm

hardening 550X1000 mm

tempering 950X1220 mm

gas carborizing 600X900 mm

cyaniding case depth upto .6mm

nitriding 2400X750X900mm

case depth upto .5~.85mm

induction hardning 470X670mm

flame hardening 600mm

subzero treatment -80

salt bath hardening 340X600

soft nitriding case depth .3mm

springmanufacturing of wire =.3-10mm

iner dia of spring=1.2-100mm

outer dia of spring=1.8-120

length of spring=4-1000mm

sub zero treatment cooling capacity

114

min temp=-120

shot blasting m/c rotating table dia=1500mm

rdt 150 max w.p height=1600mm

max hight capicty=500kg

sand blasting m/c

inspection facilities

General terms used are

1- Hardening

2- Tempering

3- Softening a Hardened Structure

Heavy Industries Taxila 20

4- Re-crystallization

5- Stress relief

6- Hot-working operations

7- Diffusion of Alloying Elements

- Hardening

Steels can be heat treated to high values of hardness and strength levels.

Structural components subjected to high operating stress need the high strength of a

hardened structure.

e.g. tools such as dies, knives, cutting devices, and forming devices need a hardened

structure to resist wear and deformation

- Tempering

As-quenched hardened steels are so brittle that even slight impacts may cause

fracture.

Tempering is a heat treatment that reduces the brittleness (increase the ductility of

a steel without significantly lowering its hardness and strength).

All hardened steels must be tempered before use.

- Recrystallization

If a metal is cold worked, grains or crystals deform (become elongated) and in

doing so harden and strengthen a metal.

There is a limiting amount of cold work that a particular metal can be subjected

to.

In rolling of steel into thin sheets, you can reduce the cross-sectional area to some

extent before it gets too hard to roll.

At this point it would be desirable to return the grains to their original shape.

Heat treatment can achieve this. The transformation of cold-worked grains to an

undistorted shape is called re-crystallization.

- Stress Relief

One of the most frequent reasons for heat treatment is to remove internal stresses from a

metal that has been subjected to cold working or welding

-Annealing

Heavy Industries Taxila 21

is a technique used to recover cold work and relax stresses within a metal. Annealing

typically results in a soft, ductile metal. When an annealed part is allowed to cool in the

furnace, it is called a "full anneal" heat treatment. When an annealed part is removed

from the furnace and allowed to cool in air, it is called a "normalizing" heat treatment.

During annealing, small grains recrystallize to form larger grains. In precipitation

hardening alloys, precipitates dissolve into the matrix, "solutionizing" the alloy.

Case hardening

Case hardening is specified by hardness and case depth. The case depth can be specified

in two ways: total case depth or effective case depth.

IRON CARBIDE DIAGRAM

Heavy Industries Taxila 22

SHOP-12

FM Khanzada Muhammad Azeem

Heavy Industries Taxila 23

FORGING

Forging is the term for shaping metal by using localized compressive forces. Hot

forging is done at a high temperature, which makes metal easier to shape and less likely

to fracture.

In shop-12 there are following m/cs under working

1. Pneumatic hammer 250 Kg

2. Chamber type gas heating furnace

3. Pneumatic hammer 750 kg

4. Chamber type gas heating furnace

5. Chamber type gas heating furnace

6. Double disc friction press 300 ton

7. Open type double column press

8. Porous type end heating furnace

9. Box type resistance furnace

10. Brinnel hardness tester

11. Floor type grinder m/c

12. Tack pin heading m/c

13. Black smith furnace

14. Surface plate

15. Shot blasting thumbling m/c

16. Electric single beam cream

17. Hacksaw m/c

18. Hydraulic press m/c

19. Rockwell hardness tester

20. Hydraulic shear

21. Hacksaw m/c

Heavy Industries Taxila 24

Process:

Forging changes the size and shape, but not the volume, of a part.  The change is made

by force applied to the material so that it stretches beyond the yield point.  The force must

be strong enough to make the material deform.  It must not be so strong, however, that it

destroys the material.  The yield point is reached when the material will reform into a

new shape.  The point at which the material would be destroyed is called the fracture

point.

   Most metals are hot forged; for example, steel is forged at temperatures between

2,100oF and 2,300oF (1,150oC to 1,260oC). 

Open-die drop-hammer forging

Open-die forging is also known as smith forging. In open-die forging a hammer comes

down and deforms the workpiece, which is placed on a stationary anvil. Open-die forging

gets its name from the fact that the dies (the working surfaces of the forge that contact the

workpiece) do not enclose the workpiece, allowing it to flow except where contacted by

the dies. Therefore the operator needs to orient and position the workpiece to get the

desired shape.

Impression-Die Drop-Hammer Forging

Impression-die forging is also called closed-die forging. In impression-die work metal is

placed in a die resembling a mold, which is attached to the anvil. Usually the hammer die

is shaped as well. The hammer is then dropped on the workpiece, causing the metal to

flow and fill the die cavities. The hammer is generally in contact with the workpiece on

the scale of milliseconds. Depending on the size and complexity of the part the hammer

may be dropped multiple times in quick succession. Excess metal is squeezed out of the

die cavities; this is called flash. The flash cools more rapidly than the rest of the material;

this cool metal is stronger than the metal in the die so it helps prevent more flash from

forming. This also forces the metal to completely fill the die cavity. After forging the

flash is trimmed off.

Heavy Industries Taxila 25

Press forging

Press forging is variation of drop-hammer forging. Unlike drop-hammer forging, press

forges work slowly by applying continuous pressure or force

The main advantage of press forging, as compared to drop-hammer forging, is its ability

to deform the complete workpiece.

Upset forging

Upset forging increases the diameter of the workpiece by compressing its length. Based

on number of pieces produced this is the most widely used forging process.A few

examples of common parts produced using the upset forging process are engine valves,

couplings, bolts, screws, and other fasteners.

Heavy Industries Taxila 26

SHOP-10&14

AWM Sana ul Haq

Introduction To Casting

In casting processes, a solid material is first melted, heated to proper temperature,

and sometimes treated to modify its chemical composition.

The molten material, generally metal, is then poured into a cavity or mold that

contains it in the desired shape during solidification.

Thus, in a single step, simple or complex shapes can be made from any material

that can be melted. The resulting product can have virtually any configuration the

designer desires.

Because of these features, casting is one of the most important of the

manufacturing processes.

Casting Terminology

Heavy Industries Taxila 27

SANDCASTING

Sand casting, by far the most popular of the casting processes, uses ordinary sand

as the primary mold material.

The sand grains are mixed with small amounts of other materials, such as clay and

water, to improve moldability and cohesive strength, and are then packed around

a pattern that has the shape of the desired casting.

Because the grains will pack into thin sections and can be used economically in

large quantities, products spanning a wide range of sizes and detail can be made

by this method.

If the pattern must be removed before pouring, the mold is usually made in two or

more pieces.

Centrifugal casting

Centrifugal casting is used as a means of casting small, detailed parts or jewelry. An

articulated arm is free to spin around a vertical axle, which is driven by an electric motor

or a spring. The entire mechanism is enclosed in a tub or drum to contain hot metal

should the mold break or an excess of metal be used. Single use molds are prepared using

the lost wax method. A small amount of metal in a crucible (a sort of ceramic pan) next

to the mold is heated. When the metal is molten the arm is released, forcing (by

centrifugal force) the metal into the mold. The high forces imposed on the metal

overcome the viscosity, resulting in a finely detailed workpiece.

Heavy Industries Taxila 28

Heavy Industries Taxila 29

Patterns and Pattern Materials

The first step in making a sand casting is the design and construction of a pattern.

This is a duplicate of the part to be cast, modified in accordance with the

requirements of the casting process, metal being cast, and particular molding

technique that is being used.

The pattern material is determined primarily by the number of castings to be made

but is also influenced by the size and shape of the casting, the desired dimensional

precision, and the molding process.

Wood patterns are relatively easy to make and are frequently used HIT when

small quantities of castings are required.

Wood, however, is not very dimensionally stable. It may warp or swell with

changes in humidity, and it tends to wear with repeated use

SHOP-16&17

Engr. Mumtaz Ahmad

Heavy Industries Taxila 30

Boiler house

A boiler is a closed vessel in which water or other fluid is heated. The heated or

vaporized fluid exits the boiler for use in various processes or heating applications.

A steam boiler in which water circulates within tubes and heat is applied from outside the

tubes. The outstanding feature of the water-tube boiler is the use of small tubes exposed

to the products of combustion and connected to steam and water drums which are

shielded from these high-temperature gases.

water tube boiler is a type of boiler in which water circulates in tubes heated externally

by the fire. Water tube boilers are used for high-pressure boilers. Fuel is burned inside the

furnace, creating hot gas which heats water in the steam-generating tubes. The heated

water then rises into the steam drum. Here, saturated steam is drawn off the top of the

drum.

.

Boiler specifications

(water table type boiler with max steam pressure 13 kg/cm2)

Heavy Industries Taxila 31

Tubes =914

Burners =2

Inlet temp of water =60-70 c

Boiler capacity =10 ton /hr

Accessories

Safety valve : It is used to relieve pressure and prevent possible explosion of a

boiler.

Water level indicators: They show the operator the level of fluid in the boiler,

also known as a sight glass, water gauge or water column is provided.

Bottom blowdown valves: They provide a means for removing solid particulates

that condense and lay on the bottom of a boiler. As the name implies, this valve is

usually located directly on the bottom of the boiler, and is occasionally opened to

use the pressure in the boiler to push these particulates out.

Continuous blowdown valve: This allows a small quantity of water to escape

continuously. Its purpose is to prevent the water in the boiler becoming saturated

with dissolved salts. Saturation would lead to foaming and cause water droplets to

be carried over with the steam - a condition known as priming..

Steam drum internals, A series of screen, scrubber & cans (cyclone separators)..

Circulating pump: It is designed to circulate water back to the boiler after it has

expelled some of its heat.

Feed water check valve or clack valve: A non-return stop valve in the feedwater

line. This may be fitted to the side of the boiler, just below the water level, or to

the top of the boiler.

Top feed: A check valve (clack valve) in the feedwater line, mounted on top of

the boiler. It is intended to reduce the nuisance of limescale. It does not prevent

limescale formation but causes the limescale to be precipitated in a powdery form

which is easily washed out of the boiler.

Heavy Industries Taxila 32

Desuperheater tubes or bundles: A series of tubes or bundles of tubes in the

water drum or the steam drum designed to cool superheated steam. Thus is to

supply auxiliary equipment that doesn't need, or may be damaged by, dry steam.

Compressor

A reciprocating compressor or piston compressor is a positive-displacement

compressor that uses pistons driven by a crankshaft to deliver gases at high pressure.

It is a piston and cylinder device with (automatic) spring controlled inlet and exhaust

valves. Delivery is usually to a receiver. The receiver is effectively a store of energy used

to drive (eg) compressed air tools.

Cycle Analysis

The cycle may be analysed as

two non-flow (compression and expansion) processes and

two flow processes (delivery and induction)

Compressor Efficiency

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The Thermodynamic Cycle

Tips for Safe Air Compressor Operation

Check the oil level to make sure the compressor is properly lubricated.

Adjust the pressure for the tool you will be using and the job you will be

doing. Never exceed recommended pressure for the tool or the job.

Always wear safety glasses and hearing protection when using a compressor.

Check the compressor frequently for any visible problems.

Ensure the pressure safety-valve ring is properly operating.

Use regulated, compressed air and never uses more air pressure than is

necessary.

Don’t forget the air filter. All air compressors have an air filter to keep the dirt

and dust out of the compressor pump. If you

run the compressor in a dusty environment, check and clean the air filter

often.

AC PLANT

(Shop-4)

Heavy Industries Taxila 34

Air-conditioning is a process that simultaneously conditions air; distributes it combined

with the outdoor air to the conditioned space; and at the same time controls and maintains

the required space’s temperature, humidity, air movement, air cleanliness, sound level,

and pressure differential within predetermined limits for the health and comfort of the

occupants, for product processing, or both.

Reciprocating Compressors

In a reciprocating compressor, as shown in fig rankshaft connected to the motor shaft

rives single-acting pistons moving reciprocally in the cylinders via a connecting rod.

The maximum compression ratio Rcom for a single-stage reciprocating ompressor is

about 7. Volumetric efficiency v drops from 0.92 to 0.65 when Rcom is raised from 1

to 6. Capacity control of reciprocating compressor including: on-off and cylinder

unloader in which is charge gas is in short cut and return to the suction chamber.

Refrigeration Condensers

A refrigeration condenser or simply a condenser is a heat exchanger in which hot

gaseous refrigerant s condensed into liquid and the latent heat of condensation is rejected

to the atmospheric air, surface ater, or well water. In a condenser, hot gas is first

desuperheated, then condensed into liquid, and finally ubcooled.The capacity of a

condenser is rated by its total heat rejection Qrej, in Btu/hr, which is defined as the

total heat removed from the condenser during desuperheating, condensation, and

subcooling.

Evaporator

An evaporator is a heat exchanger in which the liquid refrigerant is vaporized and

extracts heat from he surrounding air, chilled water, brine, or other substance to produce

a refrigeration effect.

SHOP -4

AWM M. Arif

Heavy Industries Taxila 35

Tool mfr shop

Cutting tools

a cutting tool (or cutter) is any tool that is used to remove metal from the workpiece by

means of shear deformation.

Types:

Non-grinding cutting tools often can be classified as linear or rotary, depending on

whether they rotate while cutting. Linear cutting tools include tool bits (single-point

cutting tools) and broaches. Rotary cutting tools include drill bits, countersinks and

counterbores, taps and dies, milling cutters, and reamers. Other cutting tools, such as

band saw blades and fly cutters, combine aspects of linear and rotary motion.

Selection of cutting tools

Principal categories of cutting tools include single point lathe tools, multipoint mlling

tools, drills, reamers, and taps. All of these tools may be standard catalog items or tooling

designed and custom-built for a specific manufacturing need.

To effectively select tools for machining, a machinist or

Engineer must have specific information about:

the starting and finished part shape

the workpiece hardness

the material's tensile strength

the material's abrasiveness

the type of chip generated

the workholding setup

the power and speed capacity of the machine tool

Changes in any of these conditions may require a thorough review of any cutting

tool selection.

Heavy Industries Taxila 36

Different machining applications require different cutting tool materials. The deal cutting

tool material should have all of the following characteristics:

harder than the work it is cutting

high temperature stability

resists wear and thermal shock

impact resistant

chemically inert to the work material and cutting fluid

Cutting Forces

Cutting force

Radial force

Axial force

Tool Wear

Crater wear

Flank wear

Tool life

Criteria for tool life

– Change of quality of the machined surface

– Change in the magnitude of the cutting force

– Change in the cutting temperature

– Costs

Tool Life Equation

V = cutting speed, fpm

T = tool life, minutes

C = a constant

n is a constant

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– HSS = 0.10 to 0.15

– Carbides = 0.20 to 0.25

– Ceramics = 0.6 to 1.0

EDM wire cutting m/c (Switzerland)

Axis = 5 (x,y,z,u,v)

U,V axiz are used for taper

Wire used = brass (015 ~.33 mm)

Rated power = 9.7 Kw

Current (generator) =45 A

Voltage = 3X400V 50/60 HZ

Compressed air =7-8 bar

EDM die sinking m/c

Magazine =50

Oil used = paraffin with +100 c flash pt

Electrodes = copper ,tungsten

Software =SO2

Rated power =8.3 KVA

Current =12 A

Max w/p weight =800 Kg

Drivers = X,Y,Z,C axes

Max electrodes =50 Kg

Safety Notes of Cutting Tools

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These cutting tool materials are very hard but brittle. They may be broken by shock or

excessive clamp force.

• Carbide base materials, in particular, can be very heavy. Handle with care when

transferring and storing.

• When brazing the cutting tool material, use the proper temperature to prevent the tool

from breaking.

The cutting edge is very sharp; wear gloves when handling or installing tools to prevent

injury.

• When machining, cutting tools may be broken due to shock, excessive tool wear or

improper conditions.

Use protective materials such as safe guards, safety eyeglasses, and gloves to prevent

injury.

• Depending on workpiece material and cutting conditions, sparks or fire may occur. Use

protective material

such as safe guards, safety eyeglasses and gloves.

• When machining, flying chips or metal pieces may be dangerous. Use protective

materials such as safe guards and safety eyeglasses to prevent injury.

Quality control

WM Muhammad Ashraf

Heavy Industries Taxila 39

Quality Control (QC) is a system of routine technical activities, to measure and control

the quality of the inventory as it is being developed. The QC system is designed to:

(i) Provide routine and consistent checks to ensure data integrity, correctness, and

Completeness;

(ii) Identify and address errors and omissions;

(iii) Document and archive inventory material and record all QC activities.

QC activities include general methods such as accuracy checks on data acquisition and

calculations and the use of approved standardized procedures for emission calculations,

Measurements, estimating uncertainties, archiving information and reporting. Higher tier

QC activities include technical reviews of source categories, activity and emission factor

data, and methods.

Quality Assurance (QA) activities include a planned system of review procedures

conducted by personnel not directly involved in the inventory compilation/development

process. Reviews, preferably by independent third parties, should be performed upon a

finalized inventory following the implementation of QC procedures. Reviews verify that

data quality objectives were met, ensure that the inventory represents the best possible

estimates of emissions and sinks given the current state of scientific knowledge and data

available, and support the effectiveness of the QC programmed.

Company quality

The company-wide quality approach places an emphasis on three aspects:-

1. Elements such as controls, job management, defined and well managed processes,

performance and integrity criteria and identification of records

2. Competence such as knowledge, skills, experience, qualifications

3. Soft elements, such as personnel integrity, confidence, organizational culture,

motivation, team spirit and quality relationships.The quality of the outputs is at

risk if any of these three aspects is deficient in any way.

Engineering management

Heavy Industries Taxila 40

AWM Liaqat Ali

EM Branch Descom was established 1992 through bifurcation of EM branch of mother

factory HRF(T) then called P-711 section of tooling p/g and control was transferred from

sp Gp.

EM Branch is holding 35 persons against the auth of 55 persons.

Engineering Management is a term that is used to describe a specialized form of

management that is required to successfully lead engineering personnel and projects.

Departments in Em Branch

Production planning section

Production control section

Technical support section

Tooling section

Design section

Cost evaluation cell

Inter section requisition

Working procedure

Component planning

Tool planning

Loading

Payment workorders

Processing of payment workorder

Cost evalutions

Technical security of procurement indents

Tech security of LP in

Revision of scale book

Draughting and designing

Problem areas

CNC CONTROL ROOM

Heavy Industries Taxila 41

AWM Nowshad Khan

REVERSE ENGINEERING

Reverse engineering, as the name implies, is the reverse of this; in other words, the

attempt to recapture the top level specification by analyzing the product - "attempt"

because it is not possible in practice, or even in theory, to recover everything in the

original specification purely by studying the product.

Thus, reverse engineering generally consists of the following stages:

1. Analysis of the product

2. Generation of an intermediate level product description

3. Human analysis of the product description to produce a specification

4. Generation of a new product using the specification.

Pro/ENGINEER is a parametric, integrated 3D CAD/CAM/CAE solution created by

Parametric Technology Corporation (PTC). It was the first successful, parametric,

feature-based, associative solid modeling software on the market. The application runs on

Microsoft Windows, Linux and Unix platforms, and provides solid modeling, assembly

modelling and drafting, finite element analysis, and NC and tooling functionality for

mechanical engineers.

Heavy Industries Taxila 42

Hit products

Present production includes under mentioned world class products:-

Tank ‘Al-Khalid’:

It is an outcome of a decade long joint effort of highly dedicated, skilled and motivated,

Pakistani and Chinese engineers. It is a medium weight tank having high agility and excellent

maneuverability. Incorporation of the latest electronic equipment has placed Al-Khalid

amongst the leading contemporary tanks of the world.

Tank ‘Al-Zarrar’.

The T-59 tank is basically half a century old design. Project Al-Zarrar was conceived to keep

the armour fleet of Tanks T-59 and T-69, operationally and technologically compatible with

modern tanks by upgrading its firepower, mobility and armour protection at a fraction of the

cost of latest Main Battle Tanks.

Heavy Industries Taxila 43

APC ‘Talha’.

HIT has indigenously designed and manufactured APC Talha, amphibious infantry support

vehicle with 12.7 mm Machine Gun as its main armament.

Other APC,S are

APC SAAD

APC MAUZ

APC MAAZ

And other vehicles are:

Logistic Vehicle ‘Al-Qaswa’

Infantry Fighting Vehicle ‘Al-Hamza’

Security Vehicle ‘Mohafiz’

Cash Carrying Vehicle ‘Negehban’

Heavy Industries Taxila 44

References

www.wikipedia.org

www.google.com

http://www.pakdef.info/pakmilitary/army/hit.html

http://www.pakdef.info/pakmilitary/army/hit.html

www.pakistan.gov.pk

society of manufacturing engineering

IPCC Good Practice Guidance and Uncertainty Management in National

Greenhouse Gas Inventories

Nageswara Rao Posinasetti

MIlwAukee, wI 53201 USA

Government of Pakistan year book 2005-2006

Ministry of defence production

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