Heavy Mechanical Complex Texila Report

By: Talish, Salman & Hanif Page 1 of 87
Internship Report Prepared by
Talish Mahmood
Salman Bhatti
Muhammad Hanif
Department of Mechanical Engineering
Muhammad Nawaz Sharif University of Engineering
and Technology, Multan
2012-2016

ABSTRACT
eavy Mechanical Complex Texila, situated at 35 KM from capital
Islamabad, is a leading engineering enterprise in the country, under the
ministry of Industries & Production, Government of Pakistan
This engineering and manufacturing company comprises of two main production
units:
 Mechanical Works
 Foundry & Forge Works
Mechanical works started commercial production in 1971 and Forge Works started
commercial production in 1977.
The major facilities of this integrated company include Design and Engineering,
Fabrication, Machine shops, Steel Foundry, Forging, Heat treatment, Pattern
Shop, Galvanizing Shop, Assembly & Tool Room and a compressive Quality
Assurance is set-up in addition to other infrastructure facilities.
H

PREFACE
Practical knowledge has become important in the industrial environment to
produce products for the service of mankind. The knowledge of manufacturing
practices is highly essential for all engineers for familiarizing themselves with
modern concepts of manufacturing technologies. The basic need is to provide
practical knowledge of manufacturing processes to all the internee students.
Therefore, an attempt has been made through this internship to present the
practical knowledge. Considering the general needs of internee students and the
fact that they hardly get any exposure to hand tools, equipment’s, machines and
manufacturing setups, this internship will be very useful to them in their future.
At the end, we thank Ms. Huda Hanif, Mr. Qaiser Naeem Butt, Mr. Mehran and
Mr. Khaliq Dar for their special support and guidance.
Talish Mahmood
Salman Bhatti
Muhammad Hanif

ACKNOWLEDGEMENT
In performing our work at HMC, we had to take the help and guideline of some
respected persons, who deserve my greatest gratitude. The completion of this work
gives me much Pleasure. I would like to show my gratitude to the following
Parsons
1. Mr. Amjad
(Incharge Technical Training Department)
& his team
2. Mr. Qaiser Naeem Butt
(Incharge Layout Section of Fabrication)
3. Mr. Mehran
(Welding Engineer Fabrication Shop)
For giving me a good guideline for to develop my career throughout numerous
consultations.
I would also like to expand our deepest gratitude to a person that has support me
all the time gave me such opportunity for the development of my career
Dr. Ijaz Bashir Mr. Khaliq Dar
(D.G.M Design Deptt.) (D.G.M Production Forging)
&
Dr. Gul Hameed Mr. Aon Ali
(C.C MNS UET Multan) (Lecturer MNS UET Multan)
and to all those who have directly and indirectly guided me while doing my work
at Heavy Mechanical Complex Texila, Punjab, Pakistan.

Table of Contents
ABSTRACT ......................................................................................2
PREFACE ........................................................................................3
ACKNOWLEDGEMENT......................................................................4
Literature View of Heavy Mechanical Complex Texila.........................................................6
Production Planning and Control................................................................................................9
Fabrication Shop .............................................................................................................................14
Machine Shop...................................................................................................................................39
Heat Treatment Shop ....................................................................................................................51
Non-Destructive Testing Lab ......................................................................................................58
Technology Department in HFF .................................................................................................62
Pattern Shop.....................................................................................................................................64
Foundry Works ................................................................................................................................70
Forging Shop ....................................................................................................................................73
Material Testing Laboratory .......................................................................................................77
Assembly Shop.................................................................................................................................82
Quality Control & Inspection.......................................................................................................86

Literature View of Heavy Mechanical Complex Texila
1.1 Introduction
eavy Mechanical Complex Texila, situated at 35 KM from capital Islamabad, is a
leading engineering enterprise in the country, under the ministry of Industries
& Production, Government of Pakistan
This engineering and manufacturing company comprises of two main production units:
 Mechanical Works
 Foundry & Forge Works
Mechanical works started commercial production in 1971 and Forge Works started
commercial production in 1977.
The major facilities of this integrated company include Design and Engineering,
Fabrication, Machine shops, Steel Foundry, Forging, Heat treatment, Pattern Shop,
Galvanizing Shop, Assembly & Tool Room and a compressive Quality Assurance is set-up
in addition to other infrastructure facilities
1.2 Departments
 Sales and Marketing Department
 Design and Engineering Department
 Production Planning and Control Department
 Production Shops (HMC1 & HMC2)
 Quality Assurance Department
 Project Management Department
 Human Resources Department
 Finance and Budgeting Department
H
1
Chapter

Heavy Mechanical Complex Texila
1.3 Facilities
 Fabrication
 Machining
 Heat Treatment
 Casting
 Forging
 Galvanizing
 Tool Making
 Assembly
 Design and Engineering with well-equipped Computer Aided Design (CAD) facility
 Well-equipped Quality Assurance Department with ISO 9001 Certification and
authorization to use ASME STAMPS, PP, S, U, U2
1.4 Products
 Sugar Plants
 Alcohol Plants
 Cement Plants
 Chemical and Petro Chemical Plants
 Oil and Gas Processing Plants
 Industrial Steam Boilers
 Thermal and Hydral Power Plants
 Road Construction Machinery
 Railway Equipment
 Over Head Traveling Cranes
 General Steel Structures
 Highly Sophisticated Castings and Forgings
 Items for Defence and Strategic Industry

Heavy Mechanical Complex Texila
1.5 Quality Certification
 ISO 9001
Scope
Design, engineering, manufacturing and commissioning of plants and machinery
including cement, sugar, thermal, hydro, chemical, oil and gas processing plants,
agriculture machinery, boilers, pressure vessels, heat exchangers, cranes, road
construction machinery, steel structures, plain and alloyed steel castings, free and
automatic die forgings, steel billets and other similar heavy engineering equipment.
ASME
ASME STAMPS
U: Pressure vessel according to ASME section VIII, Div. I
U2: Pressure vessel according to ASME section VIII, Div. II
S: Power Boilers
PP: Pressure Piping
 First class manufacturer of fusion welded pressure vessels
 Registered as Qualified Construction Company
1.6 Major Achievements
 Pioneer in getting ISO 9001 certification and helped other local industries to
acquire ISO 9001 certification
 Acquired Authorization from American Boiler Board to use ASME STAMPS for
power boilers, pressure vessels and pressure pipes
 Attained capability to design, engineer, manufacture machinery for turn-key
supply of higher module sugar and cement plants
 Pursue a dynamic marketing and engineering product diversification, policy as a
consequence diversified into energy sector (Thermal and Hydral Power Plants)
and oil & gas processing industry etc.

Production Planning and Control
2.1 Introduction
PPC department has been organized with the objective of improving company’s perform
ance. The department is headed by a Dy. GM Incharge PPC and comprises of the following
objectives;
► Make complete Plan for the Execution of Project
► Provide digital data to every shop section in collaboration with EDP to make ease
in processing and manufacturing of a particular job
► Manage Inventory in collaboration with Material handling section
► Make feasibility and Quantitative detail as well as processing planning and tool
designing in collaboration with Production Technology department
► Manage input and output of material in collaboration with Dispatch Cell
2.2 PPC Sections
In heavy mechanical complex PPC department is properly organized and work as team
with the following sections
► Project Planning
► EDP/CP
► Material Handling
o MMG
o General Stores
► Production Technology
o Feasibility and Quantitative Detail
o Process Planning & Tool Designing
► Dispatch cell
► ICR
2
Chapter

Production Planning & Control
Cluster Diagram of PPC

2.2.1 Project Planning
Project Planning department are established to achieve the following objectives with
exact milestone in organized way to ensure its performance,
► To ensure receipts of all drawings and documentation from design as per contact
and accelerate the schedule for production and procurement.
► To issue “material purchase requirement” to MMG.
► To prepare “bill of material” to be purchased.
► To co ordinate with the production technology for preparation of necessary
documents for production.
► To prepare and issue job orders and follow up.
► To suggest alternate materials from stock to design.
► To prepare data and reports for ICR and for survey by FBR.
2.2.2 Core Planning
Core planning department also called Electronic data processing department performs
the following functions,
► Master schedule planning
► Order activity planning
► Monitoring all schedules / shop scheduling
► Maintenance of balance order position.
► Monthly sales and production reports
► Sales / production budget.
► Project review. Meeting and follow up.
► Data entry, loading data and processing data
2.2.3 Material Handling
Material handling department works in collaboration with two departments to ensure its
objectives
► Material Management Group
o Material requirement planning
o Indenting and follow up of indents
o To keep update purchase status for all the project demands
o Establish stock levels for general consumable items and raw materials
o Issuance of materials to the appropriate job

o To keep and maintain update levels for the store items
o To look after stores and related things
► General Stores
o To receive, issue all the materials, and equipment in stores as per laid
down procedure
o Maintain detailed record of store movements
o Maintain stock location system
o Maintain daily submission of issue and receipt statement to concerned
department to keep store areas secure and organized
2.2.4 Production Technology Department
Production Technology Department work to achieve the following objectives,
► Feasibility study and quantitative details of client’s requirements for cost estimate
► Prepare details per list, route cards, cutting plans, time sheets and process maps
for all the processes
► Designing of all types of press tools, dies, templates, jigs and fixtures
► Prepare drawings for machinery components, cutting planes, marking templates
for shops etc.
2.2.5 Dispatch Cell
Dispatch cell works under PPC and has following objectives,
► To receive finished jobs from shops
► To draw standard items from store for dispatch to customer
► To organize packing
► To organize transportation
► Ensure complete accurate documentation with each product
2.3 Sale Order Numbering System
The sales order numbering system allocates a unique identification system to each
order acquired by the sales and marketing department. This sales order consists of six
digits. The first two of these numbers designate the product group number of the
products to be manufactured or services to be provided by the organization. The next two
digits specify the fiscal year in which the order is received and the last two digits give the
number of similar orders already received in the same fiscal year.

For example, a job order given as
2.4 Work Procedure of PPC
Sale
Order
No.
111601
11 Product No for Suger Group
16 Represents 2016 as Fiscal Year
01 Specifies the 1st order of this year

Fabrication Shop
3.1 Introduction
Fabrication shop located in mechanical works HMC-1 is setup to create an interracial fault
on materials/workpieces in order to obtain any type of useful assembly or equipment. In
HMC (Heavy Mechanical Complex) Fabrication shop consists of five bays i.e., one heavy
bay, two medium bays and two small bays. Bays are divided as per the capacity of the
cranes.
The above triangle shows the bays of fabrication shop along with the crane capacity.
However, these bays are further splits up into different sections as per work requirement
according to the following arrangements,
► Layout Section
► Fabrication Sections 1 to 9
► Machining Section
► Welding Section
► Hot Forming Section
Heavy Bay
Crane Capacity = 50 tons
Medium Bays
Crane Capacity = 25 &
12.5 tons
Light Bays
Crane Capacity = 5 tons
3
Chapter

Fabrication Shop
3.2 Layout Plan of Fabrication Shop

Fabrication Shop
3.3 Machinery / Equipment Installed in Fabrication
Shop
Now it time to explain all the equipment’s installed in fabrication along with their exploit
task and specification,
Heavy Bay
(Crane Capacity 50 tons)
Gas Furnace
Manufacturer China
Furnace Type Heating
Fuel Used Natural Gas
Max Temperature 1200 ℃
Purpose Heat the Workpiece for Press forming
Hydraulic Press
Manufacturer China
Press Type Hydraulic
Capacity 1000 tons
Purpose Straightening, Bending, Forming
Rolling Machine-1
Manufacturer China
No. of rollers 3
Roller Length and Dia 3.5 meter and 580 mm
Max. Sheet thickness 10-36 mm
Radial Drilling Machine
It is a small drilling machine and capable on working on small parts.
SMAW
Initial parts are made by Shield Metal Arc Welding or Manual Welding which is the most
common type of welding normally being used worldwide. Each worker used electrode
rods that are consumed within 2 to 3 minutes of continuous use. Although it is cheap it
does not perform regular fine welding.
Heating Torch
Being used by workers to bring the metal back to its original position because when once
cooled the metal pieces that are joined together due to tension solidify to cause an
unwanted deformation.

Fabrication Shop
SAW-1
Submerged Arc Welding it uses a Copper coating on the fillet wires for welding along with
fine grains being poured that acts as a flux to protect the welding from fumes and gases
produced.
Copper is used because it prevents rusting and is a good conductor of electricity. It is used
capping pass only and generates a finishing that is symmetrical and regular. It is better in
quality but expensive.
Medium Bay-I
Hydraulic Press
Manufacturer China
Press Type Hydraulic
Capacity 3000 tons
Purpose Punching, Bending, Forming
Manufactured Parts Truck Chassis
One of the largest presses of its family and generation which is unfortunately not in
working condition.
Rolling Machine-2
Manufacturer China
No. of rollers 3
Roller Length and Dia 2 meter and 280 mm
Rolling Machine-2
Manufacturer China
No. of rollers 3
Max. Sheet thickness 6 mm
Rolling Machine-4
Manufacturer Turkey
No. of rollers 3
SAW-2
SMAW Zone (beams and boilers)

Fabrication Shop
Circular Saw
Also known as the Trenjaeger Machine used to cut long bars, beams and rods straight or
any required angle. It has a limit of performing on workpieces that are 1 m in width and
450 mm in height.
I- section, H-section, Round bar, T-section, Square bar, Rectangular bar, L-section, C –
section can be performed on this machine.
Manufacturer Germany
Max Cutting Height 450 mm
Max Cutting Width 1000 mm
Angular Travel Max 45o on both sides
Cutter Blade thickness 10 mm
Blade Dia 1350 mm
Cutter Blade Material MS with HSS Cutting Tips
Medium Bay-II
(Crane Capacity 12.5 tons)
CNC Flame Cutting Machine
Plate steels are loaded on a table and parts are cut out as programmed. Some programs
are installed in it before the operations and some are modified and later added to it. Not
in working condition needs foreign expertise.
Parallel Flame Cutting Machine
Two parallel torches cut thin metal sheets in a very symmetrical fashion and hence
prevent any bending or variance on any side.
Photocell Cutting Machine
It read the sketches of the diagrams with the help of a camera which reads the black ink
of the image provided and cuts the portion from the sheet provided.
De-coiling Machine
It works on sheets ranging from 1-8 mm thickness and 2.5 metre long. Straightens sheets
and hence de-coils them.
Semi-automatic Cutting area
Here the workers use semi-automatic welding machines that use a pattern to follow on
the wheels and cut similarly e.g., if a circle is to be cut it can act like a compass from the
center or if a line at an angle needs to be formed the wheels of the small machine can be
placed on a trace line at the required angle.

Fabrication Shop
Shearing Machine-1
Three segmented blades above and below with clamps to grip the metal part is used to
cut parts that have a thickness of 12 mm or less and 2.7meter length.
350 Tone Press
Less than 25mm plates are brought here otherwise they are performed on the 1000 tone
press. It is currently used to straightens the sheets after welding.
Edge Planer
It is a 12metre long machine on which facing and beveling are performed. It’s limit of
work parts is 80 mm thick.
Small Machine Shop Area
It has two lathe machine, five radial and universal drilling machines and shaper machines.
Currently on the drilling machines holes are being made on pre-heater large plates for
boilers.
Welding Area (For boilers and beams working area)
Small Bay-I
Plasma Cutting Machine
It can cut plates 25-30 mm thick and can reach a temperature above 2000 Degree Celsius.
Only applicable on non-ferrous materials like stainless steel in which Carbon content is
less. Compressed air of 6 bars is used for cutting.
Panel Welding Machine
Multiple tubes of boilers and other tubes are joined together with straps. Each strap has
9 tubes in it. Electric welding by a 1.6 mm thick electrode is used.
Shearing Machine-2
cut parts that have a thickness of 0.5-6 mm.
Circular Saw
It is used to cut tubes, pipes with width of 200 mm and 250 mm thick.

Fabrication Shop
Die Press
It is a 100 tone press that is used to punch dies and holes inside small metal sheets after
being brought from a small furnace just besides it after the work pieces are heated to
suitable temperatures.
Nibbling Machine
Was used to sew small holes less than 1 mm diameter but is out of order.
Brake Press
160 tone brake press is capable of working on 4 m long and 1-6 mm thick parts. Most of
time this press is used to bend sheets.
100 Tone Press
After contraction/expansion of beams they lose their original shape and to be bent and
straightened back this machine used.
Straightening Machine
Strips and curved sheets are straightened in it after passing through the small rollers and
in-built presses but both units are out of order.
SAW-3 (same purpose as explained before)
Unit Cyclone Welding Area for boilers and vessels
TIG/MIG Straight Tube Belt Welding Machine (not working)
Panel Bending Machine
Produced by the Shanghai Boiler Works is bends pipes by passing them at angle through
wheels.
Small Bay-II
(Crane Capacity ≤ 5 tons)
Hot Pressing Machine
It straightens beams by applying heat.
Chinese Pipe Bending
Bends pipes by passing them at angle through wheels. Max dia. of pipe to bended is 38-
108 mm.
Pipe Squeezing Machine
Boiler headers and heat exchangers are formed here and the bending limit is 1.5 diameter
with 1-8% oval shape accepted and over 8% oval shapes rejected.

Fabrication Shop
Hot Forming Area
Furnaces and ovens are present to pre heat the parts more than 8 mm diameter.
Pipe Cutting & Bevelling Machine
German Pipe Bending
Bends pipes by passing them at angle through wheels. Max dia. of pipe to bended is 08-
60 mm.
5 Tonne Press
Conveyer Welding Area (TIG & MIG welding)
3.4 Fabrication Techniques
Metal fabrication is a value added process that involves the construction of machines and
structures from various raw materials. A fabrication shop will bid on a job, usually based
on the engineering drawings.
3.4.1 Planning and Control (CTC)
CTC stands for Central Technical Cell. Basically it’s a planning and control section of
Fabrication, in this section different drawings are analyzed and then sent to different
sections of fabrication shop depending upon the job and capacity of the shop.
Fabrication
Planning
and
Control
Marking
and Layout
Cutting
Processes
Forming &
Pressing
Joining
Processes
Tesing &
Inspection

Fabrication Shop
The main plans of CTC fabrication are as follows,
 Job feeding to shop
 Planning
 Material check
 Observation from manufacturing till sale.
3.4.2 Marking and Layout Section
Layout section of fabrication shop is established to mark the layout on the work materials
as per cutting plans and delivered the desired part to the specific section according to the
planning of CTC after performing cutting operation.
Layout section of fabrication shop consists of the following sections,
► Marking Sections
o Marking as per Drawing
o Marking as per Paper Template
o Marking as per Metallic Template (Used for Mass Production)
► Cutting Section
o Mechanical Cutting
 Shear Cutting
 Trenjaeger
CTC
Job
planning
Material
Issued to
Fabrication
Shop
Make
Cutting
Plans
Design
Tool and
Dies
Check the
Work
Deliverd as
per Route
Card

Fabrication Shop
o Flame Cutting
 Manual Gas Cutting
 Semiautomatic Gas Cutting
 Parallel Cutting Machine
 Photocell Cutting Machine
 CNC Cutting Machine
o Plasma Cutting

Fabrication Shop
► Marking Section
Marking out or layout is the process of transferring a design or pattern to a work piece,
as the first step in the manufacturing process. It is performed in many industries.
Marking out consists of transferring the dimensions from the plan to the work piece in
preparation for the next step, machining or manufacture.
Marking Tools
Typically following marking tools are utilized in HMC to transform any pattern to work
piece,
 Surface plate or marking out table
It provides a true surface from which to work.
 Angle Plates
It assists in holding the work piece perpendicular to the table.
 Scriber
It is the equivalent of a pen or pencil. It literally scratches the metal surface leaving
behind a fine, bright line.
 Height Gauge or Scribing Block
It allows lines to be scribed at a pre-set distance, from the table’s surface.
 Surface Gauge
An ungraduated comparison measuring tool that performs much the same function as
the Vernier height gage. It is often used in conjunction with a dial indicator and a
precision height gauge.
 Marking Blue
To provide a usable writing surface by covering any existing scratches and providing
a contrasting background.
 Protractor
To assist in the transfer of angular measurements.
 Tri-Square
To transfer 90° angles to the work piece.
 Punches
It pricks or centre punch to create permanent marks or dimples for drill bits to start
in Ball peen hammer used in conjunction with the punches to provide the striking
blow needed.

Fabrication Shop
 Dividers or Measuring Compass
It is used for marking out circles of any desired radius.
3.4.3 Cutting Section
Cutting Section is divided into three categories as per the requirement and suitability of
cut according to design requirement or as per thickness and finishing of cutting material,
o Flame Cutting
o Plasma Cutting
Mechanical cutting section includes two types of machines as follows
1. Trenjaeger
Also known as the Circular Saw used to cut long bars, beams and rods straight or any
required angle. Fine and accurate cut on I-section, H-section, Round bar, T-section,
Square bar, Rectangular bar, L-section, C –section can be performed on this machine.
Specification of Circular Saw
Manufacturer Germany
Max Cutting Height 450 mm
Max Cutting Width 1000 mm
Angular Travel Max 45o on both sides
Cutter Blade thickness 10 mm
Blade Dia 1350 mm
Cutter Blade Material MS with HSS Cutting Tips
2. Shear Cutting Machine
cut parts that have a thickness of 12 mm or less and 2.7meter length.
Note: In order to reduce maximum load on the punch angle of shear in provided on the
punch or die so the whole punch is not sheared at the same time.
o Flame Cutting
Flame cutting facilities in layout section includes the following machines
 Manual Gas Cutting
 Semiautomatic Gas Cutting
 Parallel Cutting Machine
 Photocell Cutting Machine

Fabrication Shop
 CNC Cutting Machine
For all these cutting machine mechanism of cutting is same but the operation is different
as per the requirement,
What is flame cutting
Gas cutting is a process of preheating carbon steel to its combustion temperature, then
burning it rapidly by means of a regulated jet of oxygen. A cutting torch is used for this
operation.
Process
The process is primarily a chemical one. It is based on the chemical relationship of oxygen
to iron metals that have been heated to a temperature of 1400° to 1600° F (760° to 871°
C). Only the metal within the direct path of the oxygen jet is affected.
In cutting, a “kerf” is formed. This is a narrow slit having uniformly smooth and parallel
walls. A skilled workman using machine cutting torch can maintain the following
tolerances with respect to squareness and straight alignment of the cut surface: 1/32nd
of an inch (.79mm) on plate thickness up to 4 inches (100mm) and 1/16th of an inch
(1.58mm) on plate thicknesses from 4 to 12 inches (100 to 300 mm).
In actual gas cutting, the iron or steel removed from the “kerf” is not entirely burned or
consumed by the oxygen. About 30 to 40 percent of the metal is washed out of the cut as
unconsumed or metallic iron due to the eroding effect of the oxygen jet.
This scouring can be seen if the sides of the kerf are inspected, because drag lines will be
faintly etched on the faces of the metal. For an incorrect cut, these drag lines will be more
pronounced. The inspection and analysis of these drag lines can be used to improve
cutting technique. (see illustration of drag lines below)
 Vertical lines – zero drag
 Drag measured against plate thickness, for example, 10% drag means a lag of 10%
plate thickness
.

Fabrication Shop
Identification of issues with Flame Cutting
The table below identifies the difference between what is desirable and what is to be
avoided with flame cut edge and how to achieve the desired result.
Shape of Cut Comments
Good cut.
 Sharp top and bottom edges.
 Vertical drag lines.
 No adhering dross.
 Square face. Light, easily removed
oxide scale.
Cutting speed too fast.
 Top edge not sharp.
 Rounded bottom edge, which may not
be
 completely severed.
 Drag lines uneven, sloping backwards.
 Irregular cut edge.
Cutting speed too slow.
 Rounded and melted top edge.
 Lower part of cut face irregularly
gouged.
 Heavy scale on cut face.
Nozzle too high.
 Excessive melting of top edge.
 Undercut at top of cut face.
Irregular cutting speed.
 Wavy cut edge. Uneven drag lines.
Preheating flame too high.
 Rounded top edge. Irregular cut edge.
 Melted metal falling into kerf.
 Excessive amount of dross adhering
strongly to bottom edge.

Fabrication Shop
Flame Cutting Equipment’s
Since the oxygen-cutting process involves directing a high-pressure jet of oxygen
continuously on to an area of steel that has been previously heated to ignition
temperature, the basic equipment’s are
o Cutting Torch
o Nozzle
o Cutting Attachments
3.4.4 Forming & Pressing Section
The forming processes modify the work piece by deforming it i.e. without removing any
material. Forming is done with a system of mechanical forces and, especially for bulk
metal forming, with heat.
The Following is important forming processes:
 Bending
 Pre-Bending
 Roll Forming
 Drawing
 Deep Drawing
 Tube Expansion
 Tube Bending
 Coining
 Spinning
 Stamping
 Embossing
 Blanking
 Piercing
 Trimming

Fabrication Shop
 Bending
Bending is a manufacturing process that produces a V-shape, U-shape, or channel shape
along a straight axis in ductile materials, most commonly in sheet metal.
 Pre-Bending
This process is performed before Roll Forming. A piece of sheet metal is bent slightly
before it is sent to a rolling machine for producing required curvature, this process is
termed as pre- bending.
 Roll Forming
Roll forming, also termed as rolling, is a continuous bending operation in which a long
strip of sheet metal (typically coiled steel) is passed through sets of rolls mounted on
consecutive stands, each set performing only an incremental part of the bend, until the
desired cross-section profile is obtained.
 Drawing and Deep Drawing
Drawing is a sheet metal forming process in which a sheet metal blank is radially drawn
into a forming die by the mechanical action of a punch. It is thus a shape transformation
process with material retention. The process is considered "deep" drawing when the
depth of the drawn part exceeds its diameter.
 Tube Expansion and Bending
In this process a tube is bended or expanded according to the desired Application.
 Coining
Coining is a form of precision stamping in which a work piece is subjected to a sufficiently
high stress to induce plastic flow on the surface of the material.
 Spinning
Metal spinning, also known as spin forming or spinning or metal turning, is a
metalworking process by which a disc or tube of metal is rotated at high speed and
formed into an axially symmetric part. Spinning can be performed by hand or by a CNC
lathe.
 Stamping
Stamping (also known as pressing) is the process of placing flat sheet metal in either
blank or coil form into a stamping press where a tool and die surface forms the metal into
a net shape. Stamping includes a variety of sheet-metal forming manufacturing processes,

Fabrication Shop
such as punching using a machine press or stamping press, blanking, embossing, bending,
flanging, and coining.
 Embossing
It’s a process used to create a shallow design on both side of a metal, so that one side is
depressed and other is raised.
 Blanking and Punching
These are the basic die cutting operations. Blanking is carried out to obtain workpiece
blanks of desired shape to carry further die operations. Punching is done to cut sludge
from stock to produce hole.
 Trimming
It is the operation of cutting of excess material at edge with which are required for
gripping purposes during press working operation.
3.4.5 Joining Operations
Most of the time during fabrication of metals three types of joining operations are used
 Soldering
 Brazing
 Welding
Soldering
The joining process in which solder mostly tin wire is used to join the parts together.
Soldering is done to prevent leakage in joints in rockets and missiles. This process is
mostly used in PCB manufacturing industries and it’s the best process for electrical joints.
Brazing
The joining process in which the parts are joined together by applying molten metal of
melting temperature less than 450℃ typically is of brass. This process is just like as gas
welding process and mostly used in precision works.
Welding
Welding is a fabrication or sculptural process that joins materials, usually metals or
thermoplastics, by causing coalescence. This is often done by melting the work pieces and
adding a filler material to form a pool of molten material (the weld pool) that cools to
become strong joint, with pressure sometimes used in conjunction with heat, or by itself,

Fabrication Shop
to produce the weld. This is in contrast with soldering and brazing, which involve melting
a lower-melting-point material between the work pieces to form a bond between them,
without melting the work pieces.
So, welding is basically the Joining metals through heating them to a molten state and
fusing them together is called the welding
Classification of Welding
Note: During my industrial training in HMC I have seen that only four types of welding
are done in Fabrication shop.
1. SMAW
Shielded metal arc welding (SMAW) is a process that melts and joins metals by heating
them with an arc established between a sticklike covered electrode and it is often called
stick welding.
The electrode holder is connected through a welding cable to one terminal of the power
source and the workpiece is connected through a second cable to the other terminal of
the power source.
The heat of the arc causes both the core wire and the flux covering at the electrode tip to
melt off as droplets the molten metal collects in the weld pool and solidifies into the weld
metal. The lighter molten flux, on the other hand, floats on the pool surface and solidifies
into a slag layer at the top of the weld metal.
Gas
Weldin
g
Oxy-
Acetylen
e Gas
Welding
Electric Arc Welding
SMAW SAW GMAW GTAW PAW FCAW ESW
High Energy
Welding
EBW LBW

Fabrication Shop
Purpose of Flux on Welding Electrode
Flux on the electrode performs four functions as follows
 Protection from atmosphere
 Deoxidizer
 Arc Stabilization
 Metallic Addition
Advantages
Welding equipment is relatively simple, portable, and inexpensive as compared to other
arc welding processes. For this reason, SMAW is often used for maintenance, repair, and
field construction.
Disadvantages
Gas shield in SMAW is not clean enough for reactive metals such as aluminium and
titanium. The deposition rate is limited by the fact that the electrode covering tends to
overheat and fall off when excessively high welding currents are used. The limited length
of the electrode (about 35cm) requires electrode changing, and this further reduces the
overall production rate.

Fabrication Shop
2. GTAW
Gas–tungsten arc welding (GTAW) is a process that melts and joins metals by heating
them with an arc established between a non-consumable tungsten electrode and the
metals.
The torch holding the tungsten electrode is connected to a shielding gas cylinder as well
as one terminal of the power source. The tungsten electrode is usually in contact with a
water-cooled copper tube, called the contact tube, which is connected to the welding
cable (cable 1) from the terminal. This allows both the welding current from the power
source to enter the electrode and the electrode to be cooled to prevent overheating. The
workpiece is connected to the other terminal of the power source through a different
cable (cable 2).
Shielding gas goes through the torch body and is directed by a nozzle toward the weld
pool to protect it from the air. Protection from the air is much better in GTAW than in
SMAW because an inert gas such as argon or helium is usually used as the shielding gas
and because the shielding gas is directed toward the weld pool. For this reason, GTAW is
also called tungsten–inert gas (TIG).
Polarity of Current in GTAW
 DCEN (Direct Current Electrode
Negative)
 DCEP (Direct Current Electrode
Positive)
 AC Current

Fabrication Shop
3. GMAW
Gas–metal arc welding (GMAW) is a process that melts and joins metals by heating them
with an arc established between a continuously fed filler wire electrode and the metals.
Shielding of the arc and the molten weld pool is often obtained by using inert gases such
as argon and helium, and this is why GMAW is also called the metal–inert gas (MIG)
welding process. Since non inert gases, particularly CO2, are also used, GMAW seems a
more appropriate name. This is the most widely used arc welding process for aluminum
alloys.
Advantages
 Like GTAW, GMAW can be very clean when using an inert shielding gas.
 The main advantage of GMAW over GTAW is the much higher deposition rate, which
allows thicker workpieces to be welded at higher welding speeds.
 The skill to maintain a very short and yet stable arc in GTAW is not required
Disadvantages
 GMAW guns can be bulky and difficult-to-reach small areas or corners.
4. SAW
Submerged arc welding (SAW) is a process that melts and joins metals by heating them
with an arc established between a consumable wire electrode and the metals, with the
arc being shielded by a molten slag and granular flux. This process differs from the arc

Fabrication Shop
welding processes discussed so far in that the arc is submerged and thus invisible. The
flux is supplied from a hopper, which travels with the torch. No shielding gas is needed
because the molten metal is separated from the air by the molten slag and granular flux.
Direct-current electrode positive is most often used. However, at very high welding
currents (e.g., above 900A) AC is preferred in order to minimize arc blow.
Advantages
 Since the arc is submerged, spatter and heat losses to the surrounding air are
eliminated even at high welding currents.
 Both alloying elements and metal powders can be added to the granular flux to control
the weld metal composition and increase the deposition rate, respectively.
 Because of its high deposition rate, workpieces much thicker than that in GTAW and
GMAW can be welded by SAW.
Disadvantages
 Relatively large volumes of molten slag and metal pool often limit SAW to flat-position
welding and circumferential welding (of pipes).
 High heat input can reduce the weld quality and increase distortions.

Fabrication Shop
3.4.6 Welding Defects and Remedies
Shape of Defects Causes Counter Measures
Cracks
 Improper Preheat
 Inadequate Thickness
 Wrong Procedure
 The welding ended far too
abruptly
 Wrong Consumable
 Proper heat
 Use Right Filler Wire
 Qualify Procedure
 Preheat Uniformly
Lack of Fusion
 Root gap too small
 Electrode size to big
 Inadequate Current
 Wrong Torch angle
 Improper bead placement
 Use Right Current
 Train/Qualify Welder
Porosity
 Rust, grease, moisture
 Impure Argon Gas
 Argon Leak within Torch
 Defective Filler Wire
 Wet surface of BM
 Rusted / Pitted Filler wire
 Replace Argon Cylinder
 Replace Leaking Torch
 Replace Filler Wire
 Clean & Warm BM
 Clean Filler Wire
Slag Inclusion
 Inadequate Current
 Improper bead placement
 Wrong torch angle
 Clean each bead
 Use right current

Fabrication Shop
Undercut
 Excess Current
 Excess Voltage
 Improper Torch angle
 Reduce the Current
 Reduce Arc length
 Train & Qualify the Welder
Lack of Penetration
 Wrong Direction of Arc
 Improper bead
placement
 Improper weaving
technique
 Reduce Root Face
 Increase Root Opening
3.5 Out Side Shop
 Channel High Beam Rolling
It increases the toughness and reduces hardness of the material being subjected to it.
 Angle Iron Cutting Machine
 Shot Blasting & Sand Blasting
Shot and Sand Blasting are performed for Surface Cleaning especially removing the
rust and corrosion that is generated on the finished goods before sending them to the
next shop.

Fabrication Shop
3.6 Recommendations
 The exhaust system is not sufficient enough and more units should be installed
especially near the welding areas to suck out the welding gases produced.
 There is no proper ventilation as most of the windows are closed/jammed.
 Welding fumes are very hazardous and workers should be provided with free face
masks, gloves, goggles, helmets etc. with strict and proper checking of the defaulters.
 More advanced machines like CNC laser cutting and water jet cutter should be
installed and replace manual machines to save time and increase production and
efficiency.
 Bending CNC machines are more accurate and efficient.
 Finished products placed outside the fabrication shop should have a proper storage
team as they are affected by corrosion, moisture and rain resulting in damage of the
goods to be sent to the consumers. Such materials should be used that are corrosion
resistant. These machines not in working condition should be immediately repaired
without any delay no matter what the cost is.
 Welding defects should be avoided. Further details are provided in NDT Section.
 Quality assurance is the main priority and supervisors should check where the
workers are doing wrong to save time in case the goods are rejected.
 More SMAW machines should be used because it is not only cheap but also performs
fine and regular finishing.

Machine Shop
4.1 Introduction
Machine shop is considered as one of the most important shops of Heavy Mechanical
Complex as it contributes a major part in the income of the industry. In this shop different
type of actions and works can be performed with the help of different machines each
perform unique work which is performed under the supervision of experienced workers
having experience of decades which definitely cannot be compared with the theoretical
work of anyone else.
Machine shop engineers always try to complete job with minimum cost but at the same
time quality would also not be sacrificed so lots of factors are included in a shop which
makes it unique and compatible.
A theory named as FIVE Ms is adopted by different industries in order to survive in this
competitive market which is as following
Five M’s
Here following five M`s are followed for the purpose of good management
 Man power
 Equipment/Machines
 Methods
 Materials
 Money
Division of Shop
Due to the load of job the machine shop is divided into two main sections
 Machine shop 1
 Machine shop 2
4
Chapter

Machine Shop
4.2 Sequence of Operation
“It is defined as the plan through which workers and engineers have to complete
the required job according to availability of machines “
Explanation
The whole procedure of job making in machine shop may be summarize in an easy way
that at first the request of job is received by PPS department in machine shop they analyse
it carefully and make drawings that helps workers to understand their job along with the
plan which makes easy for them to accomplish goal within the time limit according to the
availability of machines in machine shop or other shops machines may also be used to
fulfil the job. This job then forwarded to Incharge of section according to the size of the
job so it’s the duty of Incharge and engineers available there to assign the job to any
experienced worker which can effectively perform the job with minimum usage of
material it does not only save material but also so many other things like cost, time,
electricity and man power required for that job.
4.3 Raw Materials Used in Machine Shop
The selection of best material is an important task performed by specially experienced
persons, the task is not only to choose the appropriate material for the job but it should
be economical which decrease its cost in market but the quality may not be sacrificed.
 Mild Steel
 Steel 45
 Stainless Steel
 Bronze
 Brass
 Ferrous Metal
 Nonferrous Metal
4.4 Products Seen in Machine Shop
The tour of machine shop helps us to witness the machining and other process on the
required job. It also helps to understand the modern requirement of the industries, sugar
mills, boilers etc.

Machine Shop
Following is the list of jobs we saw in machine shop.
 Pulley
 Parts of boiler
 Parts of sugar mill
 Barrel
 Gears
 Hub
4.5 Tools used in Machine Shop
Tool is probably one of the most important component of any sort of machine. The ability
and durability of tool predicts the quality and nature of machining on the job.
There are lots of tools but few important tools we saw in machine shop are:
 Boring Tool
Used in the process of boring.
 High Speed Steel (HSS)
Used for different sort of purposes including threading. Mostly used in lathe
machines.
 Tapping Tool
Used for internal threading.
 Broaching Tool
Used to produce splines.
 Turning Tool
Used for turning operation.
4.6 Machines/Equipment installed in Machine Shop
Machine shop1 consist of various kinds of machines each having its unique identity and
importance in this sector. This kind may not only be classified as for functions only but
the maximum capacity of the machine may also be considered so according to the
capacity of job and the availability of crane the machine shop 1 is divided into three bays
which are as follows
 Small bay
 Medium bay
 Heavy bay

Machine Shop
In these bays the following machines are installed for the production of various
types of simple and complex objects,
 Lathe machine (Three jaws and four jaws chucks, turret)
 Planer machine
 Shaper Machine
 Milling machine
 Cylindrical Grinding Machine
 Drilling machine
 HDL (Heavy duty lathe)
 BVT (Boring vertical turret lathe machine)
 Gear hobbing machine
 Gear shaper machine
 Straight bevel machine
 Horizontal lathe machine
 Radial drilling machine
 Slotting machine
 Double housing planner
 Face plate machine
 Column drilling machine
4.7 Machining Operations
Machining
 A material removal process in which a sharp cutting tool is used to mechanically
cutaway material so that the desired
part geometry remains.
 Most common application includes
to shape metal parts.
 Machining is the most versatile and
accurate of all manufacturing
processes in its capability to produce
a diversity of part geometries and
geometric features (e.g. Screw
threads, gear teeth, flat surfaces).

Machine Shop
Classification of Machined Parts
1. Rotational - cylindrical or disk-like shape
Achieved by rotation motion of the work part e.g. turning and boring.
2. Non-rotational (also called prismatic) - block-like or plate-like
Achieved by linear motion of the work part e.g. milling, shaping, planning and sawing.
Turning and Related Operations
 Turning
A single point cutting tool removes material from a rotating work piece to generate
cylindrical shape. The tool is fed linearly in a direction parallel to the axis of rotation
Performed on a machine tool called a lathe.
 Facing
Tool is fed radially inward to create a flat surface.
 Chamfering
Cutting edge cuts an angle on the corner of the cylinder, forming a "chamfer".
 Threading
Pointed form tool is fed linearly across surface of rotating work part parallel to axis of
rotational a large feed rate, thus creating threads.

Machine Shop
Lathe Machines
 Most lathe machines are horizontal but vertical lathe machines are also used for jobs
with large diameter relative to the length and for heavy work
 The size of the lathe is designated by swing and maximum distance between centres
 Swing is the maximum work part diameter that can be rotated in the spindle
 Maximum distance between centres indicate the maximum length of a workpiece that
can be mounted between headstock and tailstock centres
 350 mm x 1.2 m lathe means a swing of 350 mm and maximum distance between
centres of 1.2 m
Methods of Holding the Work in a Lathe
There are four common methods used to hold work parts in turning-to grasp the work,
center and support it in position along the spindle axis, and rotate it:
 Holding the work between centres
 Chuck
 Collet
 Face plate

Machine Shop
Boring Machine
 Boring is similar to turning. It uses a single-point tool against a rotating work part
Difference between boring and turning:
 Boring is performed on the inside diameter of an existing hole
 Turning is performed on the outside diameter of an existing cylinder
 In effect, boring is an internal turning operation
 Machine tools used to perform boring operations are called boring machines
 Boring machines may be Horizontal or vertical - refers to the orientation of the axis of
rotation of machine spindle
Vertical Boring Mill
 A vertical boring mill –for large, heavy work parts
 Usually the work part diameter is greater than its length
 Typical boring machine can position and feed several cutting tools simultaneously

Machine Shop
Drilling
 Machining operation used to create a round hole in a work part
 Contrasts with boring which can only enlarge an
existing hole
 Cutting tool called a drill or drill bit-a rotating
cylindrical tool which has two cutting edges on its
working end
 Customarily performed on a drill press
Milling Operation and Machine
 A machining operation in which work is fed past a rotating tool with multiple cutting
edges
 Axis of tool rotation is perpendicular to feed direction
 Creates a planar surface; other geometries possible either by cutter path or shape
 Owing to the variety of shapes possible and its high production rates, milling is one of
the most versatile and widely used machining operations
 Milling is an interrupted cutting operation-the teeth of the milling cutter enter and
exit work during each revolution
 Cutting tool called a milling cutter, cutting edges called "teeth"
 Machine tool called a milling machine
Basic Types of Milling Operations
Peripheral milling or plain milling:
 Cutter axis is parallel to surface being machined
 Cutting edges on outside periphery of cutter
Face milling
 Cutter axis is perpendicular to surface being milled
 Cutting edges on both the end and outside periphery of the cutter

Machine Shop
Hobbing
Hobbing is a machining process for making gears, splines, and sprockets on a hobbing
machine, which is a special type of machine. The teeth or splines are progressively cut
into the work piece by a series of cuts made by cutting 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 It is the most widely used gear cutting process
for creating spur and helical gears and more gears are cut by hobbling than any other
process since it is relatively quick and inexpensive.
Types of Gears
 Spur Gears
 Helical Gears
 Worm Wheel
 Sprocket
 Bevel Gear
 Spiral Bevel
 Rack and Pinion
Cutters Used for Gear Cutting
 Mechanical Cutter
 Hob Cutter
 Disc type Cutter
 Taper shank Cutter
 Sprocket Cutter
 Blades
Shaper Machine
A shaper is a type of machine tool that uses linear relative motion between the work piece
and a single-point cutting tool to machine a linear toolpath. Its cut is analogous to that of
a lathe, except that it is (archetypally) linear instead of helical. (Adding axes of motion
can yield helical toolpaths, has also done in helical planning.) A shaper is analogous to a
planner, but smaller, and with the cutter riding a ram that moves above a stationary work
piece, rather than the entire work piece moving beneath the cutter. The ram is moved

Machine Shop
back and forth typically by a crank inside the column; hydraulically actuated
shapers also exist.
Planar Machine
A planer is a type of metalworking machine tool that uses linear relative motion between
the work piece and a single-point cutting tool to machine a linear toolpath. Its cut is
analogous to that of a lathe, except that it is (archetypally) linear instead of helical. A
planer is analogous to a shaper, but larger, and with the entire work piece moving on a
table beneath the cutter, instead of the cutter riding a ram that moves above a stationary
work piece. The table is moved back and forth on the bed beneath the cutting head either
by mechanical means, such as a rack and pinion drive or a leadscrew, or by a hydraulic
cylinder.
4.8 Tool Room
Tool room in machine shop serves the purpose of sharpening the tools which are used in
whole machine shop. They do not only make the damaged tools usable but can also make
new tools.
The machines used in tool room are following
 Tool sharpening and cutting machine
It is a multiple purpose tooling machine used to sharpen the edge of cutting tools or to
cut it in the required way. Different types of wheels or cups are used for facing and
sharpening mostly silicon carbide cup wheel are used they are best for tip grinding and
facing of the cutting tool.
The cutting process actually depends on the speed or RPM so a cutting tool design must
be strong enough to bear all such stresses.
Specifications
Speed of rotation 28-80 rpm
Max. work diameter 250mm
 Pedestal Grinding Machine
This particular machine performs the actions just similar to the grinding machine. They
are used for shinning and facing the cutting tools it may be used for sharping the tip also.
Silicon carbide wheel is used for grinding according to the worker daily they have to
change that wheel 3 to 4 times as it all consumes while grinding the metal piece or cutting
tool.

Machine Shop
 Lathe Cutting Tool
Lathe machine is known as “the mother of all machines” as it’s also the most widely used
machine in machine shop due to its versatility and easy usage. The continuous usage of
lathe machine requires the continuous supply of cutting tool as well which can only be
managed if a machine like Lathe cutting tool is available. It sharpens the cutting tool of
lathe and make it readily available even if the tool is damaged.
4.9 Production Planning Section
Production Planning Section is an important section of machine shop which plans the
whole job making procedure and way through which it has to be treated. Another
important action which it performs is the preparation of technical drawings which helps
workers to understand the proper dimensions of the job along with the properties of
material which is required for that specific job.
Working
 Monthly schedule
 Job order
 Receiving
The job order can further be classified as
 Drawing sets
 Component list
 Cutting plan
 Drawing set planning
 Loading
 Machining
 Inspection
 Assembly
 Dispatch cell
Routes
The route of job may differ according to its requirement but normally it follows following
route

Machine Shop
Route 1
I. Forging process
II. Heat treatment shop
III. Machining
IV. Assembly shop
Route 2
I. Fabrication shop
II. Machining
III. Assembly shop
Route 3
I. Casting
II. Heat treatment shop
III. Machining
IV. Assembly shop
4.10 Recommendations
► All lathe machines are operated manually which not only results in delay of job
completion but it then also totally depends on the experience and qualification of that
specific worker.
► Maintenance issues also affecting the productivity of machine shop due to which the
assembly shop is just bounded to specific small area not large enough for assembling
of different jobs.
► First aid facilities are not enough. Workers prefer not to wear uniform which leads
them in extreme danger of damaging themselves or may lose any organ.
► Cranes does not have bells so the people working on ground used to work in extreme
danger while cranes loading heavy jobs over their heads.
► The machines are old enough to work perfectly as it may also be concluded through
the installation dates of each machine (mentioned in the specifications of machine).
So, modern machinery should be introduced which may help to increase the
production along with the quality and durability of the job.

Heat Treatment Shop
5.1 Introduction
This Shop involves various heating and cooling procedures performed to effect micro-
structural changes in a material, which in turn affect its mechanical properties.
Heat treatment operations are performed in HMC at various times during its
manufacturing sequences. In some cases, the treatment is applied prior to shaping. In
other cases, heat treatment is used to relieve the effects of strain hardening that occur
during forming, so that the material can be subjected to further deformation. Heat
treatment is also performed at or near the end of the sequence to achieve the final
strength and hardness required in the finished product.
Heat Treatment is process of heating a material to a specific temperature, then cooling at
a specific rate to achieve specific mechanical properties. Iron-Iron Carbide Phase Diagram
(Iron Carbon Phase Diagram) is an important guide for heat treatment of different types
of plain carbon steel.
5
Chapter

Heat Treatment Shop
5.2 Heat Treatment Processes
The heat treatments performed are
1. Annealing
Annealing is the process of slowly raising the temperature about 50ºC (90ºF) above the
Austenitic temperature line or line ACM in the case of Hypo eutectoid steels (steels with <
0.77%Carbon), about 50ºC (90ºF) in case of eutectoid steel and 50ºC (90ºF) into the
Austenite-Cementite region in the case of Hypereutectoid steels (steels with > 0.77%
Carbon). It is held at this temperature for sufficient time for all the material to transform
into Austenite or Austenite-Cementite as the case may be. It is then slowly cooled at the
rate of about 20ºC/hr. (36 ºF/hr.) in a furnace to about 50 ºC (90 ºF) into the Ferrite-
Cementite range. At this point, it can be cooled in room temperature air with natural
convection. The grain structure has coarse Pearlite with ferrite or Cementite (depending
on whether hypo or hyper eutectoid). The steel becomes soft and ductile.
It is performed:
 To reduce hardness and brittleness
 To alter microstructure so that desirable mechanical properties can be obtained
 To soften metals for improved machinability or formability
 To re-crystallize cold worked metals
 To relieve residual stresses induced by prior shaping processes
2. Normalizing
Normalizing is the process of raising the temperature to over 60 º C (108 ºF), above line
A3 or line ACM Fully into the Austenite range. It is held at this temperature to fully convert
the structure into Austenite, and then removed from the furnace and cooled at room
temperature under natural convection. This results in a grain structure of fine Pearlite
Heat Treatment Processes
Annealing Normalizing Hardening
Full
Hardening
Surface
Haedening
Case
Hardening
Tempering

Heat Treatment Shop
with excess of Ferrite or Cementite. The resulting material is soft; the degree
of softness depends on the actual ambient conditions of cooling. This process is
considerably cheaper than full annealing since there is not the added cost of controlled
furnace cooling. The main difference between full annealing and normalizing is that fully
annealed parts are uniform in softness (and machinability) throughout the entire part;
since the entire part is exposed to the controlled furnace cooling. In the case of the
normalized part, depending on the part geometry, the cooling is non-uniform resulting in
non-uniform material properties across the part. This may not be desirable if further
machining is desired, since it makes the machining job somewhat unpredictable. In such
a case it is better to do full annealing.
Hence:
 Fine pearlite
 Higher strength and hardness
 Lower ductility
3. Quenching/Hardening
It consists of heating the metal to a suitable temperature (upper critical temperature),
holding at that temperature for a certain time (soaking), and cooling rapidly. The cooling
rate depends upon the quenching medium and the rate of heat transfer within the steel
workpiece.
Various quenching media used in HMC are
 Brine – salt water
 Fresh water
 Still oil
Brine quenching is the fastest and air quenching is the slowest.
4. Tempering
It is a heat treatment applied to hardened steel to reduce brittleness, increase ductility
and toughness and relieve stresses in the materials structure.
It involves heating and soaking at a temperature below the eutectoid for about an hour,
followed by slow cooling. A slight reduction in strength and hardness accompanies the
improvement in ductility and toughness.

Heat Treatment Shop
5. Surface hardening
It involves several thermo-chemical treatments applied to steels in which the
composition of the part surface is altered by addition of carbon, nitrogen or other
elements.
The processes used are:
 Carburizing
 Nitriding
 Carbonitriding
In HMC carburizing is used mostly.
Carburizing
It is the most common surface hardening treatment. It involves heating a part of low
carbon steel in the presence of a carbon rich environment so that Carbon is diffused into
the surface.
The carbon rich environment can be created in several ways:
 Pack carburizing
 Gas carburizing
 Liquid carburizing
Pack carburizing
This process produces a relatively thick layer of wood coal and a catalyst (barium
carbonate) on the part surface, ranging from 0.6-4 mm.
Gas carburizing
This method uses hydrocarbon fuels such as propane/kerosene oil inside a sealed
furnace to diffuse Carbon into the parts
Liquid carburizing
This method employs a molten salt bath containing sodium cyanide, barium chloride and
other compounds to diffuse carbon into the steel.
This method is used when machine allowance is not given and we require smooth surface.
The salt bath prevents the atmospheric air to come in contact with the part hence
preventing oxidation and chemical reactions.
Typical carburizing temperatures are 875-925 degree Celsius, well into the austenite
range. Carburizing followed by quenching produces a case hardness of around HRC = 60.

Heat Treatment Shop
Selective Surface hardening / case hardening
When we require different HRC at different surface and regions then case hardening is
applied.
Different case hardening methods are:
 Flame hardening
 Induction hardening
 Surface Hardening and then machining
 High frequency resistance heating
 Electron beam heating
 Laser beam heating
Methods used in HMC are flame hardening, induction heating and surface hardening +
machining.
Flame hardening
This method involves heating of the work surface by means of one or more torches
followed by rapid quenching via water. Fuel used is acetylene. Usually used for large and
small gears.
Typical hardness depth is about 2.5 mm both manual and automatic flame hardening
facility is available at HMC.
Induction heating
This method involves application of electromagnetically induced energy supplied by an
induction coil to an electrically conductive work part.
High frequency resistance heating
This method is used to harden specific areas of steel work surfaces by application of
localized resistance heating at high frequency (400 kHz typical). Hardness can range up
to 60 HRC.
Phosphating
It is a chemical cleaning process to remove oil, dirt and other components from the
surface of the part. Further phosphating is an electrolytic cleaning also called electro-
cleaning. In this process 312 V DC is applied to an alkaline cleaning solution (Grenadine
water 1:10) at a temperature 98-100-degree C. The electrolytic action results in the
generation of gas bubbles at the part surface, causing a scrubbing action that aids in
removal of tenacious dirt films and phosphate is being deposited on the part surface.

Heat Treatment Shop
5.3 Equipment installed in Shop
Electric Furnaces
 Car Bottom Furnace
Max. temp = 950°C
Size = 900 x 700 x 1800
Plotter and temperature indicator is attached with it.
 Box Type Air Furnace
It is small and large. Max. temp = 950 °C & Size =600 x 500 x 1200
Max. temp = 950° C
Size =450 x 450 x 950
 Pit Type Tempering Furnace
Max. temp = 950°C
 Salt Bath Furnace
Small, medium, large Temp = 550-650°C
Size =300 x 400 x 500
Temp = 700-900°C
Size =300 x 400 x 800
Temp = 1050-1270°C
Size =200 x 300 x 800
 Flame Quenching Plant
Vertical: f1200 x 600
Horizontal: f 450 x 2400
 High Frequency Induction Machine
It is insulated room; it uses 10,000 volts. It has a copper ring that induct heat to the
component’s external part, it has a mechanism of movement of job and quenching. Room
is provided with oil and water drum for the purpose of quenching.
 Cleaner
It is use to wash salt from metal surface after sand bathing.
 Manual Straightening Press
It is used to straight long and thin metallic sheets.

Heat Treatment Shop
 Electric Gas Carburizing Furnace
Temp = 950°C
Size =f 300 x 600
 Electric Tempering Furnace
Temp = 650°C
Size =f950 x 1220
 Salt Bath
Size =2000 x 2000 x 1400
 Water Quenching Tank
` Size =1500 x 3000 x 3000
5.4 Recommendations
► High frequency resistance heating machine was too old since 1960s. Machines must
be up to dated.
► Few types of machinery were under maintenance and hence must be repaired.
► Modern heat treatment techniques like laser beam heating and electron beam heating
are not used and are not provided. They must be introduced to increase the quality
and performance.

Non-Destructive Testing Lab
6.1 Introduction
The other facility of material testing provided by HMC is the non-destructive testing of
the material which means such methods of testing in which the breakage or damage of
the material is not involved. An example of this testing is the use of X-ray technology to
locate the defects internally. We can say that it undertakes X-ray, ultrasonic, die penetrant
and magnetic particles testing for surface cracks, voids, blow holes, porosity and cavity
etc. in welds, castings and forgings.
6.2 NDT Techniques
There are following tests which are being performed by the lab:
 Radiography, X-rays, Gamma rays (RT)
 Ultrasonic Testing (UT)
 Magnetic Particle Testing(MT)
 Dye Penetrant Test (PT)
 Eddy Current Test: for coating thickness
 Spectroscopy
6.2.1 Radiography (RT)
Radiographic Testing (RT), or industrial radiography, is a non-destructive testing (NDT)
method of inspecting materials for hidden flaws by using the ability of short wavelength
electromagnetic radiation (high energy photons) to penetrate various materials. The
followings steps are involved:
 Job is divided into sections
 Separate room is used for testing
 After developing process, illuminators of different ranges are used to see the defects
that are capture through the film.
6
Chapter

NDT Lab
Developing of Film
This process is consisting of following steps
 Developer: alkaline changes the exposed salt to black metallic silver 5-6 minutes
 Stop Bath: It neutralizes the developer and stop the developing process.
 Fixer: At this step, the effects of faults are fixed.
 Water Tank: It cleans the film from chemicals.
 PF. Solution: It prevents water to make spot.
6.2.2 Ultrasonic Testing (UT)
Ultrasonic testing (UT) is a family of non-destructive testing techniques based on the
propagation of ultrasonic waves in the object or material tested.
A typical UT inspection system consists of several functional units, such as the
pulser/receiver, transducer, and display devices. A pulser/receiver is an electronic
device that can produce high voltage electrical pulses. Driven by the pulser, the
transducer generates high frequency ultrasonic energy. The sound energy is introduced
and propagates through the materials in the form of waves.
When there is a discontinuity (such as a crack) in the wave path, part of the energy will
be reflected back from the flaw surface. The reflected wave signal is transformed into an
electrical signal by the transducer and is displayed on a screen. The reflected signal
strength is displayed versus the time from signal generation to when an echo was
received. Signal travel time can be directly related to the distance that the signal travelled.
From the signal, information about the reflector location, size, orientation and other
features can sometimes be gained.
Probe types
 Normal Beam Probes: radiate their sound wave perpendicular to specimen surface.
 TR Probes: separate crystal for receiving and transmitting waves
 Angle Beam Probes: probes that radiate their sound wave at an angle.
Advantages
 It is sensitive to both surface and subsurface discontinuities.
 The depth of penetration for flaw detection or measurement is superior to other NDT
methods.
 Only single-sided access is needed when the pulse-echo technique is used.
 It is highly accurate in determining reflector position and estimating size and shape.

NDT Lab
Limitations
 Surface must be accessible to transmit ultrasound.
 Skill and training is more extensive than with some other methods.
 It normally requires a coupling medium to promote the transfer of sound energy into
the test specimen.
 Materials that are rough, irregular in shape, very small, exceptionally thin or not
homogeneous are difficult to inspect.
 Cast iron and other coarse grained materials are difficult to inspect due to low sound
transmission and high signal noise.
6.2.3 Magnetic Particle Testing (MPT)
Magnetic particle Inspection (MPI) is an NDT process for detecting surface and slightly
subsurface discontinuities in ferromagnetic materials such as iron, nickel, cobalt, and
some of their alloys. The process puts a magnetic field into the part. The piece can be
magnetized by direct or indirect magnetization.
Magnet ink is used as magnetic powder which is attracted to local pole sat defects. Mostly
the white powdering is done on the job to increase the contrast before magnetizing.
6.2.4 Dye Penetrating Test (DPT)
Penetrant testing (PT), is a widely applied and low-cost inspection method used to locate
surface-breaking defects in all non-porous materials (metals, plastics, or ceramics).
Principle
DPI is based upon capillary action, where fluid having low surface tension penetrates into
clean and dry surface-breaking discontinuities. Penetrant may be applied to the test
component by dipping, spraying, or brushing. After adequate penetration time has been
allowed, the excess penetrant is removed and a developer is applied. The developer helps
to draw penetrant out of the flaw so that an invisible indication becomes visible to the
inspector. Inspection is performed under ultraviolet or white light, depending on the type
of dye used - fluorescent or no fluorescent (visible).
Inspection steps
 Pre-cleaning
 Application of Penetrant
 Excess Penetrant Removal

NDT Lab
 Application of Developer
 Inspection
Mostly cleaner for the penetrant which used are solvent and water emulsifier.
6.2.5 Eddy Current Testing (ECT)
Continuous wave eddy current testing is one of several non-destructive testing methods
that use the electromagnetism principle. Conventional eddy current testing utilizes
electromagnetic induction to detect discontinuities in conductive materials.
A specially designed coil energized with alternating current is placed in proximity to the
test surface generating changing magnetic-field which interacts with the test-part
producing eddy current in the vicinity.
Universal Crack Depth Meter X-RT-705
The crack depth meter X-RT 705 is in a fringe area of ultrasonic application. It can detect
the position, depth and angle of inclination of cracks in the surfaces of metallic materials
rapidly and accurately. As it operates on DC that’s why it is suitable for all the metals.
6.2.6 Spectroscopy
Spectroscopy is the NDT method in which the composition in terms of percentages of the
elements which constitutes the material by the help of the spectrometer i.e. polishing,
burning by tungsten electrode and pressurized by argon gas and then determination of
the results by the help of computerized software. It is basically the quick analysis of the
metallic material qualitatively and semi quantitatively mostly of the steel alloys. But non-
metallic materials are not applicable to this type of testing.
6.3 Recommendations
The recommendations for the material testing facilities in HMC are:
 The testing techniques are although sufficient enough yet they are old fashioned and
needed to replace by the modern techniques and equipment.
 The allocation of area for the labs is not sufficient enough according to their
requirement
 One does not go to the dark room without permission
 There should be protective clothing for Gamma and X-ray radiations
 Gamma radiations leaks from open roof surface which effect the workers after
reflecting back from the ceiling.

Technology Department in HFF
7.1 Major Functions
Technology department has two major functions:
 Provide feasibility study or quantitative details of a project before taking the
order
 Technology Preparation for workshops
HMC I & II has different Technology departments e.g. Technology I and Technology II.
 Technology I is responsible for fabrication, machining and assembly.
 Technology II is responsible for casting and forging.
 Technology department designs the entire process for completion of a project
including all major as well as minor details.
7.2 Work Procedure of TD
 Sales and marketing department receives a quotation about any project.
 It sends a letter to technology department and asks for its feasibility study.
 Then Technology department prepares a feasibility report to sales and
marketing department.
 Further, the report is sent to accounts department for cost analysis.
 Then, it is sent back to Sales and marketing Department, which replies the
quotation or receives the order.
7
Chapter

NDT Lab
Manufacturing
Planning
Technology Department
PPC
Order Placed
Sales & Marketing
Estimation
Manpower Working Hour Electricity
Specifies
Grades of Material Composition of Material
Determination Factors
Liquid Weight Gross Weight Finished Weight
Review Drawings
Provide BOQ & BOM
Quotation Recived
Sale & Marketing Department

Pattern Shop
8.1 Introduction
In this shop, the very first step for the casting is done. Patterns are made for moulds to be
for casting purposes. All this work is performed under the supervision of Shop in charge.
The process is performed following various steps which explained with terms as
below:
1. Drawing study of the job.
2. Add appropriate allowances to the casting material on paper work.
3. Making layout of the pattern according to the drawing on the layout board.
4. Margining the material to be used in the pattern.
5. Cutting and carving the margined parts using machines and tools.
6. Prepare core boxes for the core prints.
7. Paint according to casting parts required.
8. Assembling the pattern parts using glues, nails and tools.
9. Weighing them and noting all the dimensions.
10. Check and clearance by quality control authority in the shop.
11. Load and sending it to the desired foundry for casting processes.
12. Prepare for the next job.
8.2 Drawing Study
Drawing study means the study of the paper work in the shop before making the pattern
in shop. This step is basic step of this shop as the job depends upon it all the time. Drawing
shows, us the pattern to be made and what its dimensions are.
Drawing is actually the paper work of any job either for pattern or casted product. It can
be in two angle projections as
a) 1st angle projection
b) 3rd angle projection
8
Chapter

Pattern Shop
Both angle of projection can be implemented in this shop but mostly 3rd angle of
projection is being implemented here as we follow the metric system in Pakistan mostly.
Difference between first and third is as below
For the study of drawing one must know which angle of projection is being used in the
drawing.
 In first angle the object is in between the eye and drawing plane whereas in third angle
of projection, drawing plane is in between the eye the object.
 On drawing sheet, in first angle of projection, the front view is on the top left corner
of sheet and top view is on the bottom left corner of the sheet whereas for third angle
projection these views are inverted.
 British units indicate the drawing to be 1st whereas metric system indicated of 3rd
angle of projection.
8.3 Allowance Approximation
Adding appropriate allowances which are given on the drawing and usually there are
three types of allowances in the sheet as:
 Working allowance
 Shrinkage allowance
 Moulding allowance
 Casting allowance
 Fabrication allowance
8.4 Layout
After doing the paper work, layout of the required mould is made. This layout is made on
the layout board which is painted with white limestone solution. This drawing is made
on original scale and these dimensions are true dimensions of the required pattern. Face
blade plates are also available for the purpose of marking and checking the angle of the
object to be 90 degrees.
So there were two types of boards for the layout purposes
 Layout drawing board
 Flat plate board

Pattern Shop
8.5 Margining on Scale
When this drawing is made on the layout table, appropriate wood is used to make its
rectangular or square blocks and the curves and angles in the pattern are given to the
wood using the wooden templates for the respective parts. Usually two types of woods
are used here in this shop for wood patterns as
 Deodar
 Partal
8.6 Division of Job
These parts are made using machines in the workshop. There many machines ranging for
heavy and light weight types. On these bases the workshop can also be divided in two
types that are
 Light
 Heavy
For respective sections we have two electric supplied cranes in the workshop which can
lift weights as
 Light section crane 3 ton
 Heavy section crane 5 ton
8.7 Section of Shop
Workshop can also be divided in two major categories which are as
 Wooden section
 Metallic section
These entire patterns which are to be used for the dies making are made of metal and
mostly the metal is aluminum or copper.
8.8 Working of Core and Core-Prints
Then the core pattern and core prints are made for patterns. Core print provides seat for
the core pattern. At the end this coloured blue.
8.9 Types of Patterns
There are many types of patterns which are being used here. Some of them are as below
 Single pattern
 Split pattern with cope and drag.

Pattern Shop
 Match plate pattern (Stoke pattern).
 Sweep pattern.
8.10 Purpose of Pattern
These patterns are made in many ways to provide any of the following purpose.
 To provide a gating system in the pattern
 Easy removal of sand and material after casting
8.11 Indication of Colours
After completing the separate parts for the pattern, parts are coloured in a definite way
which is understandable for next shops e.g.
 Red indicates for cast iron foundry
 Black for core print
 Green for steel foundry
 Yellow for manganese
8.12 Assembly of Parts
After colouring, these parts are assembled using nails and glues. Some of final steps
include the weighing and noting its task accomplishing time, marking it serial number for
future use. It is sent to quality control assurance member in the workshop.
8.13 Quality Assurance
Quality assurance is made under supervision of head of QC deptt. in the workshop.
8.14 Machines Installed in Workshop
There are 18 to 20(including working and non-working) machines in the wooden section
whereas there are 6 to 8 machines in the metallic section of the workshop. Whereas a
large variety tools for hand working are also the part of the workshop.
Here we have a total number of 8 flat plates and 10 layout boards in the workshop.10 W-
benches with vices are also present in workshop. Machines with their working ranges are
as below.

Pattern Shop
Wooden Section
There 18 to 20 machines where some of them are under maintenance in the workshop.
 Bend Saw
This machine is uses a saw blade running in vertical position to cut the wood block
for use in the shop
 Wood Cutter
This used to cut apart the big log into small blocks
 Cross Cut Saw
This machine is also used to cut the wooden logs
 Saw Bend Rolling Machines
This machine is used to cut the parts at any angle
 Surface Planar
This is used to make the surface finish on the wood
 Thickness Planar
This machine is used to decrease the thickness of the wooden block when to use for
the job.
 Wood Working Joint Planar
This machine planes the joint on the wood
 Disc and Spindle Sander with variable angle for cutting and tapering
This type of machine a big disc mounted on the motor. This disc has an abrasive
material on its surface which is used to smoothen the wooden blocks when finalized.
The working bed of the machine is capable of turning at any angle to cut or taper the
surface.
 Cross Cutting Machine
This machine is capable of cutting at any angle
 Universal Milling Machine
This milling machine is capable of doing the jobs for vertical and horizontal as well as
vertical position
 Wooden lathe machine
Lathe is most important machine of all. This perform every job so called mother of all
Machines.

Pattern Shop
 The exhaust system for the shop was not working. This must be in working
condition.
 There must be big printing machine for taking printouts of drawing on original scale.
This would save work`s time and nations money
 The store room for patterns has no more room for the patterns to store, so their
must a short listing of patterns to increase space for patterns.
 CNC`s can be good new addition to the shop

Foundry Works
9.1 Introduction
A foundry is a workshop that produces metal castings. Metals are cast into shapes by
melting them into a liquid, pouring the metal in a mould, and removing the mould
material or casting after the metal has solidified as it cools. The most common metals
processed are aluminum and cast iron.
9.2 Casting Process
Casting process contain the following steps:
Pattern Making
Pattern making is the first stage for developing a new casting. The pattern, or replica of
the finished piece, is typically constructed from wood but may also be made of metal,
plastic, plaster or other suitable materials. These patterns are permanent so can be used
to form a number of moulds. Pattern making is a highly skilled and precise process that
is critical to the quality of the final product. Many modern pattern shops make use of
computer-aided design (CAD) to design patterns.
Mould Making
The mould is formed in a mould box (flask), which is typically constructed in two halves
to assist in removing the pattern. Sand moulds are temporary so a new mould must be
formed for each individual casting. A cross-section of a typical two-part sand mould. The
bottom half of the mould (the drag) is formed on a moulding board. Cores require greater
strength to hold their form during pouring. Dimensional precision also needs to be
greater because interior surfaces are more difficult to machine, making errors costly to
fix.
Melting and Pouring
Many foundries, particularly ferrous foundries, use a high proportion of scrap metal to
make up a charge. As such, foundries play an important role in the metal recycling
industry. Internally generated scrap from runners and risers, as well as reject product, is
9
Chapter

Foundry Shop
also recycled. The charge is weighed and introduced to the furnace. Alloys and other
materials are added to the charge to produce the desired melt. In some operations the
charge may be preheated, often using waste heat.
In traditional processes metal is superheated in the furnace. Molten metal is transferred
from the furnace to a ladle and held until it reaches the desired pouring temperature.
Fettling, Cleaning and Finishing
After the casting has cooled, the gating system is removed, often using band saws,
abrasive cut-off wheels or electrical cut-off devices. A ‘parting line flash’ is typically
formed on the casting and must be removed by grinding or with chipping hammers.
Castings may also need to be repaired by welding, brazing or soldering to eliminate
defects.
9.3 Advantages of Casting
 Use is widespread; technology well developed.
 Materials are inexpensive, capable of holding detail and resist deformation when
heated.
 Process is suitable for both ferrous and non-ferrous metal castings.
 Handles a more diverse range of products than any other casting method.
 Produces both small precision castings and large castings of up to 1 ton.
 Can achieve very close tolerances if uniform compaction is achieved.
 Mould preparation time is relatively short in comparison to many other processes.
 The relative simplicity of the process makes it ideally suited to mechanization.
 High levels of sand reuse are achievable
9.4 Limitations
 Typically limited to one or a small number of moulds per box.
 Sand: metal ratio is relatively high.
 High level of waste is typically generated, particularly sand, bag house dust and
spent shot.
Steel Melting Furnace
Molten metal is prepared in a variety of furnaces, the choice of which is determined by
the quality, quantity and throughput required.

Foundry Shop
Electric Induction Furnaces
Electric induction furnaces are the most common type used for batch melting of ferrous,
copper and super alloys. This method involves the use of an electrical current
surrounding a crucible that holds the metal charge. Furnace sizes range from < 100 kg up
to 15 tons. For production of super alloys and titanium, melting may be undertaken in a
vacuum chamber to prevent oxidation.
9.5 Casting Defects
S.no. Name of
defect
casting
Probable causes Suggested remedies
1 Blow holes  Excess moisture content in
Moulding sand.
 Rust and moisture on chills,
chaplets and inserts
 Cores not sufficiently baked.
 Excessive use of organic
binders
 Moulds not adequately vented
 Control of moisture
content.
 Use of rust free chills,
chaplet and clean inserts.
 Bake cores properly.
 Provide adequate venting
2 Shrinkage  Faulty gating and rising
system.
 Improper chilling.
 Ensure proper
directional Solidification
by modifying gating,
Rising and chilling
3 Porosity  High pouring temperature.
 Gas dissolved in metal charge.
 Molten metal not properly
degassed.
 Slow solidification of casting.
 High moisture and low
permeability in mould.
 Regulate pouring
temperature
 Control metal
composition.
 Ensure effective
degassing.
 Reduce moisture and
increase permeability of
mould.
4 Misruns  Lack of fluidity ill molten
metal.
 Faulty design.
 Faulty gating.
 Adjust proper pouring
temperature.
 Modify design.
 Modify gating system.
5 Hot tears  Lack of collapsibility of core.
 Lack of collapsibility of mould
 Faulty design.
 Hard ramming of mould.
 Improve core
collapsibility.
 Improve mould
collapsibility.
 Modify casting design.
 Provide softer ramming.

Forging Shop
10.1 Introduction
“Forging is a deformation process in which the work is compressed between two dies
using either impact or gradual pressure to form the part.”
It is the oldest of metal forming operations dating back to about 5000 B.C. In the modern
era, forging is an important industrial process used to make a variety of high strength
components for automotive, aerospace, defence and other applications. These
components include engine crankshafts and connecting rods, gears, aircraft structural
components, jet engine turbine parts etc. In addition, steel and other basic metal
industries use the forging process to establish the basic form of large components that
are subsequently machined to final shape and dimensions.
10.2 Forging in HMC
The total area of Forge Shop is 10369 Sq. M. which houses a wide range of hammers both
for production of free forgings & die forgings. The shop has acquired wide experience in
the field of producing die-forged parts and has manufactured variety of components for
the Automotive, Tractor and Defence Sectors successfully. Forging is HMC is done on a
large scale. HMC has this honour to work for the various big sugar, cement industries and
defence organizations as well.
Forging unit in HMC has been classified it three parts which includes Forging Shop I,
Forging Shop II and Hydraulic Press Shop with production of following products,
 Railway Axles
 Draw Hooks
 Screw Couplings
 Cement Industry Components
 Sugar Industry Components
 Boilers up to 110 ton/h
 Road Rollers
 Motor Guns
 Cranes
 Tank Equipment’s
10
Chapter

Forging Shop
Forge Shop I
Forging is carried out here in many different ways. One way to classify is through its
working temperature. Most forging operations are performed hot or warm, owing to the
significant deformation as per described by the process and the need to reduce strength
and increase ductility of the work metal. However, cold forging is also an important work.
Its advantage is result of increased strength that results from strain hardening of the
component. Technical Functioning is being done in Forge Shop I.
Forgibility: The process through which the shape is formed without flowing and without
cracking is called as Forgibility.
Forging Equipment’s:
 Hammers
 Hydraulic Presses (800 ton)
 Die-Forging Presses
A forging machine that applies an impact load is called a forging hammer whereas the
forging machine that applies gradual pressure is called a forging press. On the other hand,
the machine in which the flow of the work metal is constrained by the dies is called die
forging press.
Hydraulic Press:
The Hydraulic Press which is now being used is of 800 ton having 300 Pa pressure. The
compressor used is of 300 kg. There’s a storage tank besides this is a cooling tower for
cooling. In the vessel, there’s a capacity of 2/3 of air and 1/3 of water. Two pumps are
required for working and other pump as a storage tank. Two pumps are of 800 tons while
the third one is of 1000 ton. Red pipes indicate high pressure while Blue pipes show low
pressure.
Rolling
Rolling is process to roll the work piece in view of the desired shape or structure as per
the requirements is given.
The rolling process is being classified as follows:
 Hot Rolling
 Cold Rolling

Forging Shop
Shot Blasting Machine
It is a machine which is used to overcome the rusting on a surface by shooting blasts on
the material through a cleansing action to clear its surface. Shot blasts are done by steel,
sand etc. & the grinding medium size depends upon component like Aluminium Oxide or
Iron Oxide.
Ingot
‘’The term ingot is usually associated with a primary metal industry; it describes a large
casting that is simple in shape and intended for subsequent reshaping by processes such
as rolling or forging’’
The hollow rod containing the ingot is called the craggy device. Ingot temperature is
usually held 1250 Degree Celsius. Mandrel is used for creating hollowness. The refractory
material is a combination of Aluminium and Silica.
Upsetting is a process in which diameter is increased and length is shortened whereas
Drawing is a process in which diameter is shorten and length is increased.
Forge Shop II
Mechanical Functioning is being done in Forge Shop II. Forging is also known as the KING
OF TRADE because it makes its own tools. It is far better than casing because in casting,
we perform operations on already made part of soft metal with less core made whereas
Forging increases the lifetime of a material by 10-100 times. The material is subjected to
1300 Degree Celsius at which material melts and necessary elements which should be
vanished, they disappear. Press Forging is more safe and reliable as compare to the
Hammer Forging.
Types of Furnaces:
 Electric Furnace (thin material)
 Furnace Oil (old times)
 Gas Furnace (modern era)
In Hydraulic Press, push is being practiced to make large holes of 2-3 times larger
machines after getting them out of furnace. The following machines were present there
 Die Forging Hammer
 Upsetting Machine
 Blow Die Hammer (to and fro motion) & Blast Furnace

Forging Shop
Hydraulic Press Shop
It is one of the biggest shop in HMC. It plays an important role for pressing large ingots
and billets to convert them into their desired shape. It has the capacity to forge ingots up
to a maximum weight of 50 tons, produce finished forging weighing over 30 tons. There
are different types of furnaces which are required to form large huge parts. Many Defence
industries work is in the running position here as to strengthen the country’s defence and
ultimately resulting in an increased income of HMC. Missiles & tank barrels for defence
industry and rollers & shells for sugar industry are initially pressed and shaped etc. There are
several furnaces to reach the desired temperature for the respective billet and ingot. The shop
has special heat treatment furnaces, both vertical and horizontal, and also large oil and water
quenching tanks.
Main features of activities:
 Free forgings (4000 tons/years)
 Max. Weight of ingot (50 tons)
 Max. Weight of forging (30 tons)
 Max. diameter of ring forging (1800 mm)
Hydraulic Press
The biggest Hydraulic Press of HMC as well as of Pakistan is present in the Hydraulic
Press Shop. It is of 3150 tons and is spread over an area of 12372Sq. M. It is used for
different purposes like to make tank barrels etc.
IR Camera
IR Camera is used to measure the temperature of work piece at different stages. It is
around 1200 Degree Celsius when it comes out of the furnace and around 800 Degree
Celsius when treated after 10 minutes in Hydraulic Press.

Material Testing Laboratory
11.1 Introduction
For all the materials from which the jobs are to be made are subjected to some sort of
testing methods before the actual processing and working on it from raw material to the
final and finished jobs. The basic purpose of testing the material is to ensure adequate
and the proper composition of elements in required percentages in the material under
testing so that there will be a minimum chance of failure of job during overloading or
excessive use of the job.
There are two basic types of material testing methods:
 Destructive Testing
 Non-Destructive Testing
In destructive testing methods the forces are applied to the material until it brakes. And
by the force, extension and respective values of stress and strain the qualities and
properties are determined e.g. impact testing and surface hardness testing.
While on the contrary the non-destructive testing includes methods which do not involve
the breakage of materials. i.e. Radiography and x-ray analysis.
In HMC the following two testing laboratories are present and working efficiently for
testing of almost all type of the materials and jobs being made in HMC; they are:
 Material Testing Laboratory
 Non Destructive Testing Laboratory
11.2 Test Performed in MTL
Material testing laboratory in HMC is working very efficiently and it is divided in four
sections according to the type and requirement of the testing methods and for the sake
of easiness and proper working separately without any inconvenience.
Four sections of MTL (material testing laboratory) are following:
 Quick analysis
 Metallography
 Chemical analysis
 Mechanical testing
11
Chapter

Material Testing Lab
11.2.1 Quick analysis
Quick analysis section is located in steel foundry and is further divided into two sections.
One of them is testing by emission spectrometer and other is determination of
composition by chemical testing methods.
In spectrometer section; firstly, a sample of the molten steel is brought out in form of a
cube and solidified after which it is brought into quick analysis section in which its
surfaces are polished on grinders to make the surfaces shiny which is very necessary to
make it balanced on the spectrometer surface otherwise the high pressure argon gas will
cause any serious issues. At that time the intensity of blow holes and pores or other
surface defects are also inspected visually. After this the sample is forwarded to
spectrometer room and placed below a tungsten electrode (it is used because of its highly
refractory properties) and burned while the percentages of all the components or the
elements of the material is obtained on a computer screen processed by a prescribed
computer program. According to this result the desired percentages can be achieved by
adding desired components into molten steel in case the results are not satisfactory.
The same results can also be achieved by chemical testing which is to dissolve the specific
mass of the material in form of the chips and then it is dissolved in respective acids for
respective elements whose composition is to be determined either by titration or by
formulae. But the draw backs are that this method is long, time consuming and somehow
costly in terms of acids and chemical usage.
11.2.2 Metallography
Metallography is the process which involves the testing of materials using the
microscopes and other optical devices and then their internal structure is compared with
the desired material’s intermolecular structure.
The important uses of the metallographic study are following:
 Process control
 Presence and identity of defects
 Inclusion identification and determination of their density
 Examination of cracks, fractures and other failure mechanisms
 Evaluation of effects of corrosion and chemical attacks
 Identification of microstructure
 Grain or particle size

In metallographic section we studied and observed the microstructure of grey cast iron
sample which includes the graphite flakes with the simple microscope at 40
magnifications whereas its magnification is up to 450. Also we observed the structure of
M.S sample by digital microscope in which a digital camera is placed and the photograph
of the structure is obtained and its magnification is up to 5000.
Process Diagram of Metallographic Testing
11.2.3 Chemical Analysis
It is also a material testing facility provided by HMC in which almost all types of the
materials are tested not only from the HMC but the materials of other industries are also
tested here and its reports are considered satisfactory and authentic. A good trend by this
laboratory is that the reports are forwarded to the respective section or shops and the
tested sample is kept safely for 1 year in case of any complaint of query.
The equipment possessed by this lab is:
 Furnace used to burn the samples for respective testing. Can also be called as
incinerator.
 Hot plate, which is electric fired
 Stove, and it is also electric fired
 Chemicals and acids
The basic process is the same as in quick analysis chemical section and in the lab the
percentages of the elements in the materials is determined either by residual mass
(percentage) of the element or by the process which includes the dissolution of chips of
sample into chemicals followed by heating on hot plate or stove and then the
determination of composition by titrating this solution against a standard solution.

Materials which can be tested???
As a matter of fact, the chemical analysis lab is capable of testing every kind of sample
given to it but the usually it deals with the following materials mostly:
 Refractory materials like sand bricks, fire bricks, coal, fire brick linings etc.
 Babbling materials which includes copper, tin, lead and antimony i.e. nonferrous
materials
 Copper wires
 Aluminum ingots
 The ferrous materials include Ferro silicon and fire bricks and ferrous rocks
11.2.4 Mechanical Testing
The section of mechanical testing involves the destructive testing of the materials by
subjecting them to various stationary and varying loads.
It includes following testing machines:
 Universal testing machines of different capacities
 Impact testing machine
 Hardness tester machine
Universal Testing Machines
There are three testing machines in mechanical testing section and they are of different
capacities for respective samples. In the procedure the sample is placed in the jaws and
load is applied in the manner in which the respective quantity such as tensile strength is
to be determined. And by the calibrated gauge the respective extension is measured until
the sample breaks. After that the load-extension curve is drawn which is the
characteristic of the mechanical properties of the sample.
The reason of it being called the UNIVERSAL is that the following tests can be performed
on the same machine:
 Tensile strength test
 Bent test
 Crushing test

Impact Testing Machine
It is also a destructive test in which a sample is clamed at the bottom of the machine and
a hammer of a sufficient force let say 30 tons is impacted suddenly on the sample to break
it and respective readings are noted from the gauge on the machine.
It is usually used for the small samples and the one used in the HMC mechanical testing
laboratory is of 30/15 kg capacity.
Hardness Tester
Hardness can be defined as the ability of a material to resist the penetration. And in the
lab there are three testers used for this testing and they are:
 Rockwell Hardness Tester: used for hard materials
 Brinnel Hardness Tester: used for soft materials
 Vickers Hardness Test
The operation of both machines is same in which the sample in form a sphere is placed
on the bed of the machine and clamped. After which the load is applied in form of a
pointed rod like needle which penetrates into the sample and it is resisted by the
hardness of the sample and its value is noted by the gauge indicator.
 There is also another section of the material testing laboratory called as the
pyrometer section in which calibration of the gauges takes place by professional
personal.

Assembly Shop
12.1 Introduction
In Assembly shop of HMC like other modern industries various fastening methods are
used to mechanically attach two (or more) parts together. Many products in HMC are
assembled largely by mechanical fastening methods;
 Sugar industry machinery
 Boiler components
 Metal gates
 Cranes
 Road Rollers
 Industrial Fans (both suction and blowing)
 Small Tractors
 Electric power control panels
In HMC both temporary and permanent fastening methods are used.
1. Temporary Fastening
Those that allow for disassembly e.g., Threaded fasteners like Screw, bolts and nuts
2. Permanent Fastening
Those that create a permanent joint e.g., rivets
Assembly shop in HMC is responsible for all type of assemblies generally including
assembly of road rollers, overheard cranes, and mobile cranes, sugar and cement plant
components etc.
12.2 Assembly
Assembly is a manufacturing process in which parts (usually interchangeable) are added
to a product in a sequential manner to create a finished product
Why we prefer mechanical assembly?
 Ease of assembly
 Ease of disassembly
12
Chapter

Assembly Shop
 Mechanical assembly can be done by unskilled workers as compare to welding.
 Ease of transportation
 Easily inspected
 Saves Time
HMC provides the facility of assembly at the site saving both time and cost of the
costumer.
We divide mechanical assembly methods used in HMC into following categories:
 Threaded fasteners
 Rivets
Threaded fasteners
Threaded fasteners are discrete hardware components that have external or internal
threads for assembly of parts e.g., Screw, Bolts and Nuts
In HMC threaded fasteners are used to assemble almost every major product. From
rollers in sugar industry to boilers, cranes to road rollers, fans to metallic gates.
Screw, Bolts and Nuts
Screw and bolts are threaded fasteners that have external threads. A Screw is an
externally threaded fastener that is generally assembled into a blind threaded hole. A bolt
is an externally threaded fastener that is inserted through holes in the parts and screwed
into a nut on the opposite side.
Machine screws are used for assembly into tapped holes. Cap screws are used for higher
strength metals and to closer tolerances. Set screws are used for fastening collars, gears
and pulleys to shafts. A self-tapping screw is used to cut or form threads in a pre-existing
hole into which it is being turned.
Thread fasteners in HMC are mainly made of steel because of its good strength and low
cost. They are usually coated in Ni, Cr, Zn, and black oxide etc. for resistance to corrosion.
Washer
It is a hardware component often used with threaded fasteners to ensure tightness of the
mechanical joint. They
 Distribute stresses that might otherwise be concentrated at the bolt or screw head
and nut
 Provide support for large clearance holes in the assembled parts
 Increase spring tension

Assembly Shop
 Protect part surfaces
 Seal the joint
 Resist inadvertent unfastening
Tools and Methods for threaded fasteners
Tools used in HMC varies from simple hand held Screwdrivers or wrenches to hydraulic,
pneumatic or electric powered tools. Usually the pneumatic power tightening is done at
the site and simple manual tightening is done at the shop
Rivets
A rivet is an unthreaded, headed pin used to join two (or more) parts by passing the pin
through holes in the parts and then forming (upsetting) a second head in the pin on the
opposite side. The deforming operation is usually performed by hammering or steady
pressing.
In addition, special rivets are used for special applications. Rivets are primarily used for
lap joints.
Riveting method is used as it
 Offers higher production rates
 Simplicity
 Dependability
 Low cost
In HMC the tooling and methods used in riveting are
 Impact, in which pneumatic hammer delivers a succession of blows to upset the rivet.
 Steady compression, in which the riveting tool applies a continuous squeezing
pressure to upset the rivet
 A combination of impact and compression
 Equipment used was portable and manually operated.
12.3 Types of Fittings
Fitting is the process of joining two mechanical parts to each other
Fits
The relation between two mating parts is called fit. Depending upon the actual limits of
the hole or shaft sizes, fits may be classified as clearance fit, transition fit and interference
fit.

Assembly Shop
Clearance fit
Clearance fit is defined as a clearance between mating parts. In clearance fit, there is
always a positive clearance between the hole and shaft.
Interference fit
Interference fit is obtained if the difference between the hole and shaft sizes is negative
before assembly. Interference fit generally ranges from minimum to maximum
interference.
Transition fit
Transition fit may result in either an interference or clearance, depending upon the actual
values of the tolerance of individual parts.
12.4 Assembly Systems
Hole Basis System
The size of the shaft is obtained by subtracting the allowance from the basic size of the
hole. Tolerances are then applied to each part separately. In this system, the lower
deviation of the hole is zero. The letter symbol indication for this is 'H'.
Shaft Basis System
The upper deviation of the shaft is zero, and the size of the hole is obtained by adding the
allowance to the basic size of the shaft. The letter symbol indication is 'h'.
 Pneumatic, electric or hydraulic powered tools for fastening are not provided to
workers at the shop. This reduces efficiency, Wastes time and decreases quality.
Hence these tools must be provided.
 The bending machine is under maintenance.

Quality Control & Inspection
13.1 Quality Control Procedures
Inspection is a process in which the material is just visually Checked by using many
apparatuses like Vernier Calliper, Micro meter screw gauges, Tapes, Compasses etc.
When this is done, then a report is prepared containing all the references with respect to
that the material was passed out from the inspection stage and this is a necessary step to
assure the quality of the product. And is done where the status of the manufacturing
industry is to be maintained and the Quality of the manufactured product is too kept up
to the standards.
The working process starts with agreement between purchaser and manufacture, the
manufacture provides Preformat Invoice (PI) to the purchaser which explains the
equipment specification and related price. Then the purchaser issues the Purchase Order
(PO) which confirming the preformat invoice. Before start of manufacturing, the
purchaser must provide equipment inspection and test plan (ITP) to the manufacture.
The ITP identifies all inspection points for purchaser inspector.
Then the manufacture needs to prepare the project quality control plan based of this
inspection and test plan. The manufacture notifies purchaser inspector in advance to
attend to her factory for witnessing the inspections and tests. The communication and
coordination channel between manufacture, purchaser inspector and purchaser are
agreed in the Pre-inspection meeting (PIM). Based the international practice
manufacture sends her notification to the purchaser, and purchaser reviews the
notification and after her approval sends to the inspector.
Then the inspector will be attended in the in manufacture shop to witness the test or
inspection. The purchaser inspector will send his/her inspection visit report to the
purchaser. Purchaser can assign his/her own inspector which is her own direct employee
or hire a third party inspection agency to carry out inspection.
Inspection and test plan has tabular format and its content extracted from construction
code. In each row of the table there is quality control and inspection requirement and
13
Chapter

Assembly Shop
determine which party is responsible for control and inspection. There are three parties
in ITP:
 Manufacturer
 Third Party Inspector (TPI)
 Client or purchaser.
Final Inspection before manufacturing section consists of Pre-Inspection Meeting (PIM)
and review of quality control documents which need to be approved before start of
manufacturing. There are 3 or 4 important terminologies in the ITP which determines the
responsibility of each party. These are:
Hold point (H)
Hold on the production till TPI Inspector perform inspection and supervise the required
test, as general; attendance to the PIM meeting, raw material inspection and
identification, Post Weld Heat Treatment Review, Hydrostatic Test, Performance Test,
Run-Out Test and Final Inspection are Hold points. Normally manufactures shall notify
TPI Inspector 7 working days in advance.
Witness Point (W)
Manufacture shall notify client and TPI Inspector but there is no hold on the production,
client can waive this inspection based on his discretion and inform TPI Inspector.
Spot Witness (SW)
For items with spot witness manufacture shall notify TPI inspector as fulfilling the
monitoring for example one random visit for whole UT Tests or one or two visit for whole
surface preparation work for painting.
Review (R)
Review means Review document, which includes the review of quality control records,
test reports and etc. When TPI Inspector make visit for hold or witness point, the
inspector can review the related documents.

Heavy Mechanical Complex Texila Report

More Related Content

What's hot

Similar to Heavy Mechanical Complex Texila Report

Heavy Mechanical Complex Texila Report