BLW vocational training Report

SUMMER INTERNSHIP REPORT -2023
BANARAS LOCOMOTIVE WORKS
VARANASI – 221004
SUBMITTED TO
PRINCIPAL
Technical Training Centre
BLW/Varanasi
SUBMITTED BY:
Name: Sanjeet Kumar
Registration No: 2023071026
Training Duration: From 3 July To 28 July
Course: Bachelor of technology
Branch Name: Mechanical Engineering
Year: 3rd
College Name: Rajkiya Engineering College Azamgarh

1
PREFACE
The objective of the practical training is to learn something about industries practically and
to be familiar with the working style of a technical person to adjust simply according to the
industrial environment.
It is rightly said practical life is far away from theoretical one. We learn in class room can
give the practical exposure or real life experience no doubt they help in improving the
personality, but the practical exposure in the field will help the student in long run of life and
will be able to implement the theoretical knowledge.
As, a part of academic syllabus of four-year degree course in Mechanical Engineering every
student is required to undergo a practical training.
I am student of third year mechanical and this report is written on the basis of practical
knowledge acquired by me during the period of practical training taken at Banaras
locomotive Works, Varanasi.

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Table of Contents
INTRODUCTION TO BLW............................................................................................................. 4
BRIEF HISTORY OF BLW.............................................................................................................. 5
PRODUCT OF BLW ......................................................................................................................... 6
PRODUCTION SHOP ...................................................................................................................... 7
CHAPTER 01..................................................................................................................................... 9
LOCOMOTIVE TESTING SHOP............................................................................................... 9
1. Introduction................................................................................................................................ 9
1.1 Air Brake Test .................................................................................................................... 9
1.1.1 Components of Vacuum Brake Systems: ...................................................................... 10
1.1.2 Air Brake Test Parameters............................................................................................. 11
1.1.3 Working of Air Brake System........................................................................................ 11
1.2 Pantograph ....................................................................................................................... 12
1.2.1. Pantograph balancing test............................................................................................. 13
1.3 Shower Test............................................................................................................................. 14
CHAPTER 02................................................................................................................................... 15
LOCOMOTIVE ASSEMBLY SHOP......................................................................................... 15
2. Introduction.............................................................................................................................. 15
2.1 Diesel Locomotive assemble in LAS..................................................................................... 15
2.2 Electric locomotive assembly in LAS ................................................................................... 16
2.2.1 Middle roof assembly...................................................................................................... 16
2.2.2 Rear Roof assembly ........................................................................................................ 18
2.2.3 Pipe Duct Assembly......................................................................................................... 19
2.2.4 Auxiliary Components assembly.................................................................................... 20
2.2.5 Compressor Assembly..................................................................................................... 20
CHAPTER 03................................................................................................................................... 21
TRUCK MACHINE SHOP ........................................................................................................ 21
3. Introduction.............................................................................................................................. 21
3.1 Wheel and Axle Machining Section................................................................................ 21
3.1.1 Turning............................................................................................................................. 21
3.1.2 Drilling ............................................................................................................................. 22
3.1.3 Grinding........................................................................................................................... 22
3.1.4 Burnishing ....................................................................................................................... 23
3.2 Wheel and Axle Assembly Section........................................................................................ 24
3.3 Traction Motor Assembly...................................................................................................... 24

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3.4 Truck Frame Assembly.......................................................................................................... 25
3.5 Brake rigging assembly ......................................................................................................... 25
CHAPTER 04................................................................................................................................... 26
HEAVY WELD SHOP................................................................................................................. 26
4.1 Metal Inert Gas Arc Welding................................................................................................ 27
4.1.1 Arc Initiation in MIG Welding....................................................................................... 27
4.1.2 Advantages of MIG welding........................................................................................... 28
4.2 Tandem Auto Welding ........................................................................................................... 28
4.2.1 Materials used for tandem welding ............................................................................... 28
4.2.3 Advantages of Tandem Welding..................................................................................... 29
4.3 Submerged Arc Welding........................................................................................................ 29
4.4 Fluxed-Cored Arc Welding.................................................................................................... 30
CONCLUSION ................................................................................................................................ 32
REFERENCES................................................................................................................................. 33

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INTRODUCTION TO BLW
The Banaras Locomotive Works (BLW) (formerly Diesel Locomotive Works (DLW) in
Varanasi, India, is a production unit of Indian Railways. DLW stopped manufacturing
diesel locomotives in March 2019 and was renamed BLW in Oct 2020.
Diesel Locomotive Works (DLW) is a production unit under the ministry of railways.
This was setup in collaboration with American Locomotive Company (ALCO), USA
in 1961 and the first locomotive was rolled out in 1964. This unit produces diesel
electronic locomotives and DG sets for Indian railways and other customers in India and
Abroad.
Subsequently a contract for transfer of technology of 4000 HP Microprocessor Controlled
AC/AC Freight (GT 46 MAC)/passenger (GT 46 PAC) locomotives and family of 710
engines has been signed with electro motive division of GENERAL MOTORS of USA
for manufacture in DLW. The production of these locomotives has now started and thus
DLW is the only manufacturers of Diesel Electric Locomotives with both ALCO and
General Motors technologies in the world.
The Banaras Locomotive Works (BLW) (formerly Locomotive Works (DLW)) in
Varanasi, India, is a production unit of Indian Railways. DLW stopped manufacturing
diesel locomotives in march 2019 and was renamed BLW in October 2020.
Fig. Banaras Locomotive Works

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BRIEF HISTORY OF BLW
 Set up in 1961 as a green-field project in technical collaboration with ALCO/USA
to manufacture Diesel Electric Locomotives.
 First locomotive rolled out and dedicated to nation in January, 1964.
 Transfer-of-Technology agreement signed with General Motors/ USA in October,
95 to manufacture state-of-the-art high traction AC-AC diesel locomotives.
 In January, 1964 First Board Gauge Locomotive (WDM-2) “KUNDAN” released
by (Late) Shri Lal Bahadur Shastri.
 In November, 1968 First Meter Gauge Locomotive (YDM-4) released by (Late)
Shri Morarji Desai. (22 Nov.)
 In February, 1975 First Broad Gauge Shunting locomotive (WDS-6) turned out.
 In January, 1976 Loco exported to Tanzania.
 In March, 1977 1000th Locomotive turned out.
 In December 1977, First Diesel Generating Set Commissioned.
 In May 1984, Locos exported to Vietnam.
 In August, 1994 First 3100 HP WDM-2C loco turned out.
 In April, 1995 First 2300 HP WDP-1 Passenger loco turned out.
 In July, 1995 First 3100 HP WDG-2 Freight loco turned out.
 In December 1995, Locos exported to Sri Lanka.
 In April 1996, Locos exported to Bangladesh.
 In February, 1997 Awarded ISO-9002 Certification.
 In August, 1998 First 3100 HP WDP-2 Passenger loco turned out.
 In August, 1999 First PKD WDG-4 Locomotive turned out.
 In April, 2002 First BLW built 4000 HP WDG-4 Loco turned out.
 In June, 2002 First BLW built 3300 HP WDG-3C Freight Loco turned out.
 In June 2005, 2.4 Mw Diesel Generating Set commissioned.
 In September 2005, Certified for OHSAS – 18001:1999.
 In November, 2008 Locos exported to Mozambique.
 In October, 2010 First Dual Cab WDP-4D loco turned out.
 In February, 2012 First 5500 HP WDG-5 locomotive manufactured.
 In November, 2012 First Dual Cab WDG-4D loco turned out
 In July, 2013 1000th High Horse Power Locomotive turned out.

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 In January, 2014 Golden Jubilee Locomotive WDP4B “PRATEEK” turned out.
 In February, 2017 First electric loco WAP-7 turned out.
 In January, 2018 Obtained NABL Accreditation for Laboratories.
 March 2018, successfully converted two old ALCO diesel loco (WDG3A) into
Electric loco WAGC3 loco, this is first time in world.
 In January, 2020 IRIS Certification obtained.
 In March, 2020 First ever dual traction locomotive turned out.
 In January, 2021 Obtained certification of ISO 50001:2018 for Energy
Management System.
 December 2021 Production of 45 Locomotives in December 2021 which is all time
highest ever in a month.
 January 2022 1000th Electric loco turned out.
 March 2022 Highest ever locomotive production of 367 in 2021-22.
 November 2022 Highest ever Electric locomotive Bogies Production of 52
loco set in a month.
 June 2023 1500th Electric loco turned out.
 Production of 51 Locomotives in June 2023 which is all time highest
ever in a month.
 A large base of delighted customers among many countries viz. Sri Lanka
(December 1995), Malaysia, Vietnam (May 1984), Bangladesh (April 1996),
Tanzania (January 1976), Mozambique (November 2008) to name testimony to
product leadership in its category.
PRODUCT OF BLW
WAG 11 This engine is in trial phase of manufacturing.
WAP 7 6000 HP on wheels and having gear ratio 20 :72
WAG 9HH It can be used for both passenger and freight.
WAG 9H It’s a passenger locomotive having 6000 HPwith IGBT based 3 phase
propulsion system.
WAG 9HC It’s designed for heavy freight operations.
WDG4 4000 HP AC/AC Freight Traffic Locomotive

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WDP4 4000 HPAC/AC Broad-Gauge High-Speed Locomotive
WDG3D 3400 HP AC/AC Broad Gauge Mixed Traffic Micro-Processor
Controlled Locomotives
WDM3C 3300 HP AC/DC Broad Gauge Mixed Traffic Locomotive.
WDM3A 3100 HP AC/DC Broad Gauge Mixed Traffic Locomotive.
WDP3A 3100 HP AC/DC Broad-Gauge High-Speed Passenger Locomotive
WDG3A 3100 HP AC/DC Broad Gauge Freight Locomotive.
WDM2 2600 HP AC/DC Broad Gauge Mixed Traffic Locomotive.
WDP1 2300 HP AC/DC Broad Gauge Intercity Express Locomotive.
WDM7 2150 HP DC/DC Broad Gauge Mixed Traffic Locomotive.
WDM6 1350 HP DC/DC Broad Gauge Mixed Traffic Locomotive.
YDM4 1350 HPAC/DC & DC/DC Broad Gauge Mixed Traffic Locomotive.
EXPORT LOCO 2300 HP AC/DC Meter Gauge/Cape gauge Mixed Traffic
Locomotive.
PRODUCTION SHOP
Production shops are divided in four divisions:
01.Block Division
a. Heavy Weld Shop
b. Heavy Machine Shop
02.Engine Division
a. Engine Erection Shop
b. Engine Testing Shop
c. Light Machine Shop
d. Sub-assembly Shop
e. Rotor Shop
f. Heat Treatment Shop

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03.Loco Division
a. Loco Frame Shop
b. Pipe Shop
c. Truck Machine Shop
d. Traction Assembly Shop
e. Sheet Metal Shop
f. Loco Assembly Shop
g. Loco Paint Shop
h. Loco Test Shop
04.Service Shop
a. Maintenance Area
b. Tool Room
c. Central Transport Shop

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CHAPTER 01
LOCOMOTIVE TESTING SHOP
1. Introduction
Locomotive based vehicle systems are among the most commonly and widely used
methods of transportation, both for passengers and goods. Therefore, safety and
precaution are an important objective regarding operation for locomotive based vehicle.
Thus, various test such as Air Brake test, Pantograph balancing test, leakage test etc.
performed to locate defects and reduces chances of failure.
Fig. New Locomotive testing shop
In locomotive testing shop, there are three tests perform respective to find mechanical
defects:
1.1 Air Brake Test
In the earliest days of railways, braking technology was primitive. Viz, locomotives were
slowed or stopped by the application of manually applied brakes such as vacuum brake
and steam power brakes.
Nowadays locomotive braking system is pneumatic in nature i.e., The compressed air is
used for obtaining brake application. In Air Brake system compressed air is used for
opening the brake system. The locomotive compressor charges the feed pipe and the brake
pipes throughout the length of the train. The feed pipe is connected to the auxiliary

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reservoir and the brake pipe is connected to the brake cylinder through the distributor
valve. Brake application takes place by dropping the pressure in the brake pipe.
1.1.1 Components of Vacuum Brake Systems:
Pressure Pneuma c System Brake Cylinder
Air Compressor Air Compressor
Step down transformer DC Battery

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Air reservoir Air Blower
1.1.2 Air Brake Test Parameters
 Main Reservoir Pressure
 Brake Pressure
 Feed Pressure
 Brake Cylinder Pressure (auto A9)
 Brake Cylinder Pressure (auto SA9)
1.1.3 Working of Air Brake System
In locomotives air brake system function in 3 stages:
(a) Charging Stage
Charging stage is primary stage of air brake test in which charged air delivered to pipe
duct from compressor in form of compress air. During this stage, brake pipe is charged to
5kg/cm2
pressure which in turn charges control reservoir and auxiliary reservoir to 5
kg/cm2 pressure via distributor valve. At this stage, brake cylinder gets vented to
atmosphere through passage in Distributor valve.
(b) Application Stage
For application of brakes, the pressure in brake pipe has to be dropped. This is done by
venting air from driver`s brake valve. Reduction in brake pipe pressure positions the
distributor valve in such a way that the control reservoir gets disconnected from brake
pipe and auxiliary reservoir gets connected to brake cylinder. This results in increase in
air pressure in brake cylinder resulting in application of brakes. The magnitude of braking
force is proportional to reduction in brake pipe pressure.

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(c) Release Stage
For releasing brakes, the brake pipe is again charged to 5 kg/cm2 pressure by compressor
through driver’s brake valve. This action positions distributor valve in such a way that
auxiliary reservoir gets isolated from brake cylinder and brake cylinder is vented to
atmosphere through distributor valve and thus brakes are released.
1.2 Pantograph
A pantograph is a device used in locomotives and electric trains to collect power from an
overhead electric line. When the locomotive moves beneath the electric field section of
the track, the pantograph is raised, and collector shows come into contact with the
overhead wire. The contact between the shoes and wire allows electrical power to flow
from the wire to locomotive`s electrical system.
Fig. Pantograph
The pantograph is designed to maintain a consistent contact force with the overhead wire.
It achieves this through a combination of mechanical and pneumatic system. The
mechanical linkage allows the pantograph to follow the contours of the overhead wire,
while the pneumatic system applies the necessary force to maintain good electrical
contact.
The electrical power collected by the pantograph is then transmitted to the traction motors
of the locomotive. Which drive the wheels and propel the train forward. In this way, the
pantograph enables electric locomotives and trains to operate without the need for an
onboard power source like an internal combustion engine.

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1.2.1. Pantograph balancing test
Pantograph balancing test is mechanically performed test used to ensure the proper
alignment and balance of the pantograph device on locomotives or electrical trains.
These tests are crucial for maintaining reliable contact between the pantograph and
overhead wire, optimizing power collection, and reducing wear and tear during the
balancing test, the pantograph is subjected to various positions and load to assess its
performance and make necessary adjustments. Generally, balancing test can be performed
in three stages:
Stage 1: Positioning
The locomotive or train is positioned under the overhead wire, and the pantograph is
raised to make contact with the wire. The position of the pantograph is critical, as it should
align properly with the wire to achieve optimal contact and minimize wear.
Stage 2: Static Balancing
The pantograph is first tested for static balancing. In this test the pantograph is positioned
at different heights and angles to determine if it remains stable and balanced. Adjustments
are made to pantograph`s mechanisms, such as the counterweights or spring tension, to
achieve proper balance.
Stage 3: Dynamic Balancing
Once the pantograph is statically balanced, dynamic balancing tests are conducted. This
involves energizing the overhead wire with electrical power, simulating real real-world
operating conditions. The pantograph is then subjected to various speeds, acceleration and
track conditioned to assess its stability and performance.
During the dynamic balancing tests, engineers monitor the pantograph`s behaviours
closely. They look for any signs of bouncing, excessive vibrations, or irregularities in
contact with the overhead wire.
If any issues are observed, adjustments are made to the pantograph`s mechanical
components to correct them.

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1.3 Shower Test
Tightness of locomotive in terms of water proofing is an important factor that have a
specific impact on the performance of locomotive in several conditions such as during
rainy season. Water proofing by shower testing method is a traditional method of tightness
testing used to detect leakage in locomotive engine.
Shower test typically refers to a test conducted on a locomotive to check its water tightness
and assess any potential leaks. This test is undertaken to detect leakages around windows,
doors, cabins, covers, etc.
In this method, a shower facility is designed. This shower facility is set up to create an
artificial shower on the Locomotive engine to be tested.
Fig. Shower Test

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CHAPTER 02
LOCOMOTIVE ASSEMBLY SHOP
2. Introduction
Locomotive assembly shop deals with assembly of all mechanical and electrical
component in locomotive cell. Locomotive assembly shop is responsible for bringing
together the various component and subsystem such as air compressor, middle roof,
pantograph etc, for effective performance of locomotive engine.
Fig. Locomotive Assembly Shop
Locomotive assembly shop gets their different component form various shops like Truck
machine shop, Heavy weld shop, Heat treatment shop, Heavy machine shop locomotive
frame shop, etc. Generally, In Banaras locomotive works assembly operation can be
performed in hybrid mode. Viz, assembly process accomplished through manual and
computer pneumatic control system.
2.1 Diesel Locomotive assemble in LAS
For assembly of diesel locomotive engine Locomotive assembly shop obtain equipment’s
like under frames and assembled trucks from engine division and block division shops
like heavy machine shop, Truck machine shop, engine erection shop etc. Diesel
locomotive engine prepared in Banaras locomotive works in case of special demand made
from various PSU’s such as NTPC and GAIL. Diesel locomotives consists of several
components and assemblies such as crank case, frame, air compressor, axle wheel,
compressor, alternator etc.

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Generally, assembly process is semi-automatic because human effort as well as computer-
controlled device is used for this process.
Fig. Diesel locomotive assembly
Critical parameters that affect the engine performance like crankshaft alignment,
compressor alignment etc. are maintained within in specified limit during assembly
stage. Deck Milling of under-frame is done on a special purpose machine to ensure
proper alignment of Compressor, Engine & Alternator. Assembled loco is
dispatched further for testing.
Alternator, compressor, Traction System, DB Fan, DB resistance, Crow Bar
resistance, Radiator Fan etc. are being procured from reputed venders and received
in shop in ready to use condition and manually assemble in locomotive engine.
2.2 Electric locomotive assembly in LAS
In electric locomotive assembly loco shell, propulsion system, air compressor, pipe
network for circulation of air throughout the engine and devices such as transformer,
battery, air reservoir tank, brake cylinder, sand hopper, alternator, air blower etc and all
electric connections applied.
2.2.1 Middle roof assembly
Middle roof assembly follow application of various equipment’s for proper functionality
of pantograph and smooth distribution of current to engine section. Within the middle
roof, various electrical and pneumatic equipment, such as control systems, circuit breakers
and communication systems, are housed. The middle roof provides a dedicated space for
these vital systems, protecting them from external elements and facilitating easier
maintenance access.

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Fig. Middle Roof assembly section
Various components and their function used in middle roof assembly are as follows:
01.Vacuum circuit Breaker (VCB)
VCB used in large transmission lines to cut off power to electrical outlets in case of
short circuit or electrical malfunction to allow manual disconnection of circuits so that
they can be repaired.
02.High Voltage Bushing
A bushing is a device for carrying one or more high voltage conductors through an
earthed barrier such as a wall or a metal tank. It must provide electrical insulation for
the rated voltage and for service over voltages and also serve as mechanical support
for the conductor and external connections.
03.Primary Voltage transformer
It can raise or lower the voltage with a corresponding decrease or increase in current.
In all the electric locomotives, limiting the value of current during starting, speed
control is achieved by supply of variable voltage to the traction motors.
04.Harmonic Filter
Harmonic filters reduce distortion by diverting harmonic currents in low-impedance
paths. Harmonic filters are capacitive at the fundamental frequency, so they are also
used to produce the reactive power required by converters and for power factor
correction.

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05.Earth Switch
The earthing switch is used to interconnect and earth the phase and neutral conductors
of an electrical installation to ensure the safety of personnel during servicing.
2.2.2 Rear Roof assembly
In locomotives, the rear roof refers to the uppermost part of the locomotive's body at the
rear end. It is the covering or structure that forms the top of the locomotive's rear
section. The rear roof serves several important functions:
Fig. Rear Roof
01.Sheltering the interior
The rear roof protects the locomotive's interior and its various components from
external elements such as rain, snow, debris, and direct sunlight. This protection is
essential to ensure the reliable operation of the locomotive's equipment and systems.
02.Wiring and Equipment Enclosure
Similar to the middle roof, the rear roof may contain electrical wiring, cables, and
other equipment associated with lighting, communication systems, and various
components. Proper enclosures within the roof help keep these elements organized,
protected, and insulated.
03.Structural Support
The rear roof provides structural support to the locomotive's body, contributing to the
overall stability and integrity of the train. It helps distribute the loads and forces
experienced during operation.

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Rear roof assembly consists following equipment’s:
 Roof Line Insulator
 Pantograph Insulator
 Pantograph Insulator
 Servo Motor Application and piping
 Link Rod and Carbon Web application
 Intake Filter Bushing Fitting and Welding
 Duct and Sealant application
2.2.3 Pipe Duct Assembly
For uniform distribution of compressed air, leak proof pipe duct network established in
locomotive engine. In locomotives, pipe duct assemblies play a crucial role in transporting
fluids, gases, and other important components throughout the engine. These assemblies
consist of interconnected pipes and ducts that facilitate the flow of various substances
required for the locomotive's operation and functionality. Here are some key points about
pipe duct assemblies in locomotives:
01.Fluid and Gas Transport
Pipe duct assemblies are responsible for transporting various fluids and gases
necessary for the locomotive's operation. These can include diesel fuel, lubricating
oil, coolant for the engine, compressed air for braking systems, and sometimes
even steam for certain types of locomotives.
02.Cooling Systems
Locomotives generate a significant amount of heat during their operation. Pipe
duct assemblies are used to circulate coolant through the engine and other critical
components to dissipate heat and prevent overheating.
03.Air Intake and Exhaust Systems
The locomotive's engine requires a continuous supply of air for combustion. Pipe
ducts help channel the intake air to the engine while also directing exhaust gases
away from the engine and releasing them outside the locomotive.
This system contributes in cooling system by providing fresh air to air blower thus
increases efficiency of the system.

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04.Braking Systems
In locomotives, compressed air is used for braking. The air is stored in tanks and
delivered to the braking system through the pipe duct assemblies to actuate the
brakes.
05.Fuel Delivery
Diesel locomotives utilize pipe duct assemblies to transport fuel from the fuel tank
to the engine, where it is used for combustion to produce power.
06.Pneumatic Systems
Apart from braking, other pneumatic systems may be present on locomotives, such
as pneumatic controls for various functions. Pipe duct assemblies are used to
distribute compressed air to these systems.
07.Hydraulic Systems
Some locomotives may have hydraulic systems for certain functions, such as
controlling couplers, doors, or other mechanical devices. Pipe duct assemblies can
be employed to carry hydraulic fluid to these components.
08.Electrical Wiring Protection
In addition to fluid and gas transportation, pipe duct assemblies may also serve to
protect electrical wiring and cables from damage, especially in harsh operating
conditions.
2.2.4 Auxiliary Components assembly
Auxiliary Components refers to all the components that are used in Locomotive cabin to
provide comfort environment to Loco Pilot. For example:
 Chair
 Air Conditioner
 Wiper System, etc.
2.2.5 Compressor Assembly
Compressor is a mechanical device used to compress atmospheric air at constant pressure.
This compressed air is used in air brake system to apply brake.
Compressor accomplished availability of air to the different components of locomotive
engine such as air reservoir, air blower, brake cylinder etc.

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CHAPTER 03
TRUCK MACHINE SHOP
3. Introduction
Banaras locomotive workshop acquire different components of locomotive from different
industry and utilized own workshop for proper installation and functionality of
locomotive engine. In our first week of vocational training, we understand the
contribution of Truck machine shop in manufacturing of locomotive engine.
In Truck machine shop assembly and post machining operation performed for internal
components of locomotive components such as axle, wheel, bull gear, traction motor etc.
For higher performance and reduces chances of failure precise assembly of components
required due to this post machining and finishing required. To get desired machining fit
several manufacturing processes like drilling, reaming, boring, burnishing, grinding,
turning, etc. perform.
3.1 Wheel and Axle Machining Section
After Receiving casted axle and wheel from industry there is need of post machining for
precise fit in locomotive bogie, for these various operations performed mention are as
follows:
3.1.1 Turning
In turning process material is removed from a workpiece to create a cylindrical shape.
This process is usually performed on a CNC operated Lathe Machine, a machine tool
designed for turning operations. The workpiece rotates while a cutting tool, held in a tool
post, moves parallel to the axis of rotation to remove material and create the desired shape.
In turning operations diameter of workpiece reduces radially. Turning operations
effectively remove material from the workpiece, creating the desiredshape. This material
removal can be done quickly and efficiently, allowing for the mass production of
components.

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Fig. Turning of axle Fig. Turning of wheel
3.1.2 Drilling
In drilling process, we create holes in a workpiece. It involves the use of a rotating cutting
tool called a drill bit to remove material and form a in various industries to produce holes
for assembly, fastening, and other purposes.
Fig. Manual Drilling Machine
Drilling is a process of producing a cylindrical hole using drill bit, in a solid material.
It is a process in which a drill bit is uses to cut a hole of a circular cross-section in a
solid material. The drilling is a single purpose machine for the production of holes.
Drilling process is the best method of producing holes. The drill bit is rotary cutting
tool, a cylindrical bar with helical flutes and radial cutting edges at one end.
3.1.3 Grinding
Grinding is a precision machining process used to produce smooth and fine surfaces.
Grinding is a fundamental process in manufacturing and is used is particularly effective
for achieving tight tolerances and superior surface finishes on hard materials.
Grinding process uses oriented abrasives such as aluminium oxide, silicon carbide or
ceramic grains as cutting tool. And these abrasives have negative rake angle, which
increases the material removal force also known as cutting force. Conventional grinding
process uses higher specific energy compared to other machining process.

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Fig. Grinding of wheel
3.1.4 Burnishing
Burnishing is a surface finishing process used to improve the appearance and texture of a
material's surface. It involves rubbing or polishing the surface using a hard, smooth tool
to create a glossy and smooth finish. Burnishing is commonly applied to metals, plastics,
and even some natural materials like leather and wood. This process does not remove
material from the surface; instead, it compacts and smoothest the existing material to
achieve the desired effect.
Fig. Burnishing of axle
In truck machine shop machine assisted Burnishing operation performed. burnishing
machines or burnishing attachments can be used to achieve consistent and uniform results.
Types of Machines used in shop:
 Vertical Drilling Machine
 CNC-VTL- 03 Wheel Machining
 CNC-VTL- 03 Axle Machining
 Lathe machine for Burnishing
 Grinding Machine

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 Wheel Press Machine
3.2 Wheel and Axle Assembly Section
A railway wheelset is an assembly consisting of an axle and two wheels fitted with
interference and, where necessary, applicable associated components, e.g., gear-shaft,
bearing bushing, etc.
Wheelsets need to be safe because failures could lead to derailment and potentially to
major safety issues, including loss of life and heavy damage to railway vehicles.
Therefore, it is important to assemble the wheelset correctly to reduce accidents and
derailments. Wheelsets are assembled to remain attached to all components while in
operation. Wheels may be press-fitted or shrink-fitted to the axles. Press-fit, or
interference fit, tightens two parts together by relying on friction and joining the parts that
can take a different form.
Fig. Bear Fitting Area Fig. Wheel Assembly
3.3 Traction Motor Assembly
After fitting of these components, journal bearings are fitted on the both end of the axle.
Fig. Traction Motor Assembly (Ref. TMS) Fig. Traction Motor Assembly (Ref. Google)

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Traction Motor is fitted on the suspension tube to provide final rotational drive to wheels.
The traction motor is an electric motor specifically designed for providing the required
tractive effort or pulling power to propel the locomotive or vehicle. It converts electrical
energy into mechanical energy to drive the locomotive's wheels.
3.4 Truck Frame Assembly
In truck frame assembly shop, the truck frame assembly refers to the structure that
supports and connects the wheels and axles to the main body of the locomotive. The
primary purpose of the truck frame is to provide stability, distribute the weight evenly,
and allow the locomotive to navigate curves and uneven tracks smoothly.
Fig. Truck Frame assembly
3.5 Brake rigging assembly
This is the system by which the movement of the brake cylinder piston transmits pressure to
the brake block on wheel. Rigging can often be complex, especially under a passenger car
with two blocks to each wheel, making a total of sixteen. Rigging requires careful adjustment
to ensure all the blocks operated from one cylinder provide an even rate of application to each
wheel. If you change one block, you have to check and adjust all the blocks on that axle.
Problems related to brake rigging are:
 Brake block touches with flange.
 Brake hanger lever alignment not proper.
 Brake cylinder foundation bolt loose.

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CHAPTER 04
HEAVY WELD SHOP
4. Introduction
In heavy weld shop different types of welding operation performed to joint material in
desired orientation. Welding is a process in which localized permanent joint can be
produced with or without application of heat, with or without application of pressure or
alone and with or without application of filler material for joining of similar or dissimilar
material.
Presently welding is used extensively for fabrication of vastly different components
including critical structures like boilers and pressure vessels, ships, off-shore structures,
bridges, storage tanks and spheres, pipelines, railway coaches, anchor chains, missile and
rocket parts, nuclear reactors, fertiliser and chemical plants, structural, earth moving
equipment, plate and box girders, automobile bodies, press frames and water turbines.
Welding is also used in heavy plate fabrication industries, pipe and tube fabrication,
jointing drill bits to their shanks, automobile axles to brake drums, lead wire connections
to transistors and diodes, etc.
In heavy weld shop generally four types of welding operation performed are as follows:
01. Metal Inert Gas Arc Welding
02. Tandem Auto Welding
03. Submerged Arc Welding
04. Flux-Cored Arc Welding
Fig. Heavy Weld Shop

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4.1 Metal Inert Gas Arc Welding
Metal inert gas welding also known as MIG or GMAW is a kind of fusion welding in
which joints are formed with application of heat. In gas metal arc welding
(GMAW)process a consumable wire, of 0.8 to 2.4 mm diameter and wound in spool form,
is fed at a preset speed through a welding torch wherein it is provided the electrical
connection and the shielding gas. The power source used is invariably of the rectified dc
type. Both, constant voltage and constant current type power sources are in use.
Fig. MIG Welding (Ref. NPTEL) Fig. MIG Welding (Ref. HWS)
Depending upon the work material, the shielding gas may be argon, helium, nitrogen,
carbon dioxide, hydrogen, and their mixtures. When inert shielding gas is used the process
is more popularly known as MIG (metal inert gas) welding and when CO2 is used as the
shielding gas it is referred to as CO2 welding or MAG (metal active gas) welding.
GMAW is a very versatile process and can be used for welding all metals for which
compatible filler wires have been developed. However, its typical applications include
medium-gauge fabrication such as structural, earth moving equipment, plate and box
girders, and automobile bodies. This process has great potentials for use with robotic
welding systems.
4.1.1 Arc Initiation in MIG Welding
Arc is generated between a consumable electrode and workpiece, and electrode is in the
form of wire. Electrode continuously feed to the work piece through servo feed
mechanism at desired speed. MIG welding show steady arc characteristics this is due to
electrical discharge between two electrodes. Steady arc reduces chances of arc blow
during welding, arc blow is unwanted deflection of arc causes excessive spatter,
incomplete fusion, porosity and lower quality weld joint.

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4.1.2 Advantages of MIG welding
 Highly versatile because can be used on several material such as steel, stainless
steel, cast iron, magnesium and aluminium and can be done semi or fully
autonomously.
 It will be used for welding of more than 5 mm thickness workpiece material.
 Weld deposition and welding speed is more as compare to TIG Welding.
4.2 Tandem Auto Welding
The tandem welding process consists of two electronically isolated wires, two separate
power sources and two feed units. This means that the wires can operate independently,
allowing for respectively different current levels, i.e., pulsed or continuous operating
modes or different wire diameters. Usually, the weld occurs with the two wires along the
joint line, but the torch can be rotated around the joint.
Fig. Tandem Welding
4.2.1 Materials used for tandem welding
 Steel
 Aluminium (including alloys)
 Coated plates
 Chrome – Nickel materials
 High-strength steel
4.2.2 Applications of Tandem Welding
Locomotives consist of various heavy-duty components, such as frames, bogies, and
engine casings. Tandem welding is beneficial for welding these thick sections due to its

29
ability to deposit a large amount of weld metal quickly, resulting in faster production
times.
Some applications tandem welding that I observe in Banaras Locomotive workshop are
as follows:
 Longitudinal Welding of Train Carriages
 High Speed welding of Rails.
 Welding of large panels
 Welding of Fuel Tanks and Air Reservoirs in Diesel Locomotive.
 Chassis and Frame Welding.
4.2.3 Advantages of Tandem Welding
 Higher welding speed.
 Better penetration and fusion between the two base metals.
 Reduced specific heat input.
 Increase Joint accessibility.
4.3 Submerged Arc Welding
Submerged arc welding (SAW) is a process in which continuous copper coated spooled
wire is used in conjunction with lose granulated flux poured ahead of the arc so as to
provide a protective media to ward off the atmospheric gases from reacting with the
molten metal pool. The electrode wire diameter may range between 2 and 10 mm. Both
AC and DC power sources are used though DC with electrode positive (DCEP) is the
preferred choice.
The weld joint produced by submerged arc welding is of very high quality and
consequently this process finds extensive use in joining thick plates in long, linear seams
as are encountered in ships, pressure vessels, bridges, structural work, welded pipes, and
nuclear reactors.

30
Fig. Submerged Arc Welding
4.3.1 Application of Submerged Arc Welding
Submerged Arc Welding (SAW) finds various applications in the locomotive
manufacturing and maintenance processes. Some of the key areas where SAW is used in
locomotive include:
 Locomotive Frame Fabrication
 Assembly of bogie and suspension element
 Coupler and draft gear assembly
 Used in the fabrication and repair of locomotive exhaust systems.
4.3.2 Advantages of Submerged Arc Welding
 High Weld deposition rates.
 Deep Penetration.
 CNC operation makes easy for automation.
 Reduced health hazard for Welder.
 Minimal Welding Fumes.
 High welding efficiency.
4.4 Fluxed-Cored Arc Welding
The flux-cored arc welding (FCAW) process, is similar to gas metal-arc welding, except
that the electrode is tubular in shape and is filled with flux. Cored electrodes produce a
more stable arc, improve weld contour, and produce better mechanical properties of the

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weld metal. The flux in these electrodes is much more flexible than the brittle coating
used on SMAW electrodes, so the tubular electrode can be provided in long coiled lengths.
The electrodes are usually 0.5 to 4 mm (0.020 to 0.15 in.) in diameter, and the power
required is about 20 kW. Self-shielded cored electrodes also are available. They do not
require any external shielding gas, because they contain emissive fluxes that shield the
weld area against the surrounding atmosphere.
The FCAW process combines the versatility of SMAW with the continuous and automatic
electrode-feeding feature of GMAW. The process is economical and versatile, so it is used
for welding a variety of joints, mainly on steels, stainless steels, and nickel alloys. The
higher weld-metal deposition rate of the FCAW process (compared with that of GMAW)
has led to its use in the joining of sections of all thicknesses. The use of tubular electrodes
with very small diameters has extended the use of this process to workpieces of smaller
section size.
4.4.1 Advantages of Flux-Cored welding
A major advantage of FCAW is the ease with which specific weld-metal chemistries can
be developed. By adding alloying elements to the flux core, virtually any alloy
composition can be produced. The process is easy to automate and is readily adaptable to
flexible manufacturing systems and robotics.

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CONCLUSION
 Understand function of the basic component of locomotive engine.
 Understand the working of Air Brake Test and Pantograph Balancing Test.
 Understand importance of shower test.
 The locomotive assembly shop plays a critical role in bringing together the various
components and systems to create fully functional locomotives. Throughout the
assembly process, skilled workers, engineers, and technicians collaborate
diligently to ensure the highest standards of quality, safety, and performance are
met
 Understand function, working and purpose of different CNC operated machining
processes in Truck Machine Shop.
 the heavy weld shop in the locomotive workshop is a critical component of the
locomotive manufacturing process, where skilled welders and technicians play a
pivotal role in fabricating robust and reliable locomotives.

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REFERENCES
[1]. https://blw.indianrailways.gov.in/
[2]. NPTEL Video Lecture.
[3]. Manufacturing Engineering and Technology by Serope Kalpakjian and Steven R.
Schmid.
[4]. Welding Engineering and Technology by Dr. R.S. Parmar.
[5]. www. Indianrailways.gov.in

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