heavy industries taxila report
DESCRIPTION
Heavy Industries Taxila ReportTRANSCRIPT
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
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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.
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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
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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
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● 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
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●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
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● 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
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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
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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.
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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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