training repor of locomotive diesel shed

1. A
Report on Practical Training
taken at
“Locomotive Diesel Shed, Phulera”
From May 14 to July 12, 2018
Submitted
in partial fulfilment
for the award of the Degree of
Bachelor of technology
in Department of Mechanical Engineering
Coordinators: Submitted by:
Mr. Manoj kumar sain Govind Ram Kumawat
(Associate Professor) (15ESKME062)
Mr. Dinesh kumar sharma
(Assistant Professor)
Department of Mechanical Engineering
Swami Keshvanand Institute of Technology, Management & Gramothan, Jaipur
Rajasthan Technical University
July, 2018

3. ACKNOWLEDGEMENT
I am highly thankful and grateful to the staff and employees of LOCOMOTIVE
DIESEL SHED, PHULERA, for their kind guidance and help which helped me
to successfully complete my vocational training of 60 days. I am especially
thankful to
Shri Shashank DME/Phulera
Shri V.K. Mathur SSE/DSL/Phulera
Shri Mohan Jangid CMS/DSL/Phulera
except these all the other members were very cooperating and understanding
and were always eager to help.
I thank them all once again.
Govind Ram Kumawat
(15ESKME062)

4. ii
CONTENTS
1. Introduction 1-3
1.1 About Indian Railways
1.2 About Diesel Shed
1.3 About Diesel Shed, Phulera
1.4 Shed Infrastructure
2. General information about Diesel Shed, Phulera 4-5
2.1 Organisation
2.2 Activities
2.3 Infrastructure
2.4 Rules and Regulations
3. Classification of locomotives 6-7
3.1 Class of locomotives
3.2 Classifications of locos
4. Diesel Locomotives 8-11
4.1 Locomotive terminology
4.2 Parts of locos
4.3 Specification of YDM4
5. Diesel Engine 12-14
5.1 Diesel engine components and basic engine nomenclature
5.2 Working of Diesel engine
6. Expressor 15-16
6.1 Introduction
6.2 Construction
6.3 Working of exhauster and compressor
7. Turbo Supercharger 17
7.1 About Turbo Supercharger
7.2 Cause of Turbo Charger
8. Braking system in locos 18-21
8.1 Introduction
8.2 Types of brakes in locos
8.3 A-9 Braking system
8.4 SA-9 Braking system
8.5 Dynamic Braking system
8.6 Hand Brake system
8.7 Emergency Braking system
8.8 Advantage of Air Brake system over Vacuum Brake system
9. Bogie 22-24
9.1 Design principle
9.2 Wheelset arrangement classification
9.3 Spring

5. iii
10.Fuel oil system 25-27
10.1 Introduction
10.2 Fuel feed system
10.3 Fuel injection system
11.Water cooling system 28-29
11.1 Description
11.2 Cooling system pressurisation
Reference
30

6. 1
Chapter-1: Introduction
1.1 About Indian Railways
Indian Railways has one of the largest & busiest rail networks in the world. It comes
under the Ministry of Railways. It is the world’s largest commercial employer, with
more than 105 million employees. The fleet of includes over 200,000 wagons, 50,000
coaches, 8,000 locomotives. It also owns locomotives & coaches production facilities.
Indian Railways transporting over 20 million passengers. Indian Railways are divided
into 16 zones & each zone is made up of a certain no. of divisions. There are 67
divisions. The total length of the track used by Indian Railways is about 108,805 km
(67,608 miles.). About 50% of the total track km is Diesel. It also operates the Kolkata,
Delhi metro.
1.2 About Diesel Shed
Diesel locomotive shed is an industrial – technical setup, where repair & maintenance
works of diesel locomotives is carried out, so as keep loco working properly. It
contributes to increase the operational life of diesel locomotives and minimize the line
failure. The technical manpower of a shed also increases the efficiency of the loco.
Diesel shed usually has –
 Berths & plate for loco maintenance.
 Pits for under frame maintenance.
 Heavy cranes, lifting jacks.
 Fuel storage & lube oil storage, water treatment plant & testing labs etc.
 Sub-assembly overhauling 7 repairing sections.
 Machine shop & welding facilities.
1.3 About Diesel Shed, Phulera
Diesel shed, Phulera was established in the year 1965 as a satellite shed to attend trip
and fortnightly schedule of MG locomotives of SBI, BGKT and ABR diesel sheds. The
gauge conversion of the entire DLI-ADI route and cutting off of BGKT Diesel shed
form the BKN Division saw a requirement of a homing shed in the north part of the
Western Railway. The ideal location for the same was found in Phulera, which already
had a MG satellite shed. In 1996 Phulera shed was converted into a homing shed.
Operating under severe handicaps of infrastructure and maintenance facilities, the shed
started as a shed carrying out the Trip, Monthly schedules.
The shed during the course of the last nine years, undertook many self-imposed projects
to improve the infrastructure as well as maintenance handicaps through vigorous and
relentless efforts by the supervisors and staff. The shed is currently carrying out all the
schedules up to M9 (Half Yearly). For all the other schedules like yearly, 3 yearly and
Out of Course repair, locos are booked to Diesel POH Shop, Ajmer. Beside this shed is

7. 2
now also maintaining 5 MG locomotives at Samdari and 4 MG locomotives at Mavli-
Junction.
The shed is currently headed by Sr.DME (Diesel), who is assisted by ADME (Diesel)
and AMM. The senior supervisory cadre of shed includes 5 SSE (Diesel), 2 SSE
(Diesel-Electric) and 2 Chemist and Metallurgical Superintendent. Shed is gearing itself
to carry out yearly schedules of MG locomotives.
Fig.1.3.1 Diesel loco shed Phulera

8. 3
1.4 Shed Infrastructure
Shed area --------------------------------------------------- 2261 sq.m .
M.G setelite shed------------------------------------------1965 - 1997.
M.G home shed-------------------------------------------- from 1997.
Holdings ------------------------------------------------------------- 64.
Shedules---------------------------------------four (TI1,TI2,M3,M9).
Staff cader----------------------------------------------------------- 100.
Bearthing space------------------------------------ 9 Loco shed ule pit.
2 Loco load pit
Manufacturing------------------------------------------ ALCO/ DLW.

9. 4
Chapter-2: General information about Diesel Shed,
Phulera
2.1 Organisation
Diesel Loco Shed, Phulera is headed by Sr. DME/D/FL. He is assisted by ADME/D/FL
and other subordinate Sr. Supervisors such as SSEs at FL.
2.2 Activities
At diesel shed / Phulera M-18 and M-36 schedules of NWR MG Locomotives is carried
out. This shed is feeding depot for consumables, unit exchanges spares etc. for all NWR
satellite sheds. An EMD Loco service centre has been set up at FL, which had started
functioning since August 2010.
Fig. 2.2.1 YDM4 meter gauge rail

10. 5
2.3 Infrastructure
Important Assets
 Under floor pit wheel lathe
 A set of five, 25 T loco lifting jacks
 One EOT Crane of 10 Tone capacity
 One Stationary Compressors 300 CFM.
 One Portable Compressor.
 One Centre lathe; One Radial drill machine
 Three welding sets
 DM Plant
 Two fork lifters
Effluent Treatment Plant:
 Capacity 20,000 litre per day, helpful in recycling of water.
Material Storage:
 Two storage wards each of size 16.9 X 11.95 m2 Receipt Ward 15.0 X 5.55 m2.
2.4 Rules & Regulations
i) Railway Service conduct Rule.
ii) Disciplinary and Appeal Rule.
iii) Hours of Employment Regulation.
iv) Pass Rule.
v) Leave Rule.
vi) Pension Rule.
Instructions and Manuals:
i) Indian Railway Establishment Code.
ii) Indian Railway Financial Code.
iii) General Conditions of Contract and standard specification.
iv) Diesel Maintenance Manual.
v) General Rule and Service Rules.
vi) Accident Manual.
vii) Indian Railway Store code.
viii) Indian Railway Conference Rule-Pt.-III & IV
ix) Various technical pamphlets and instructions issued by RDSO from time to time.
x) Various instructions issued by Railway Board from time to time.
xi) General and subsidiary rule.

11. 6
Chapter-3: Classification of locomotives
Three general class of locomotives:
i. Freight locomotive – For designed with slower speed, acceleration and have
capacity to pull heavier load as compared to another.
Ex. (WDG2, WDM4)
ii. Passenger locomotive-- For designed with high speed, fast acceleration & light
loads.
Ex. (WDP2, YDP4)
iii. Shunting locomotive-- For designed with slower speed, low HP and suitable for
shunting purpose only.
Ex. (WDS4, WDS6)
a. Classification of locos
 The first digit [gauge]
 W= Broad Gauge WDM-3
 Y= Meter Gauge
 Z= Narrow Gauge ( 2 feet 6 inch)
 N= Narrower Gauge (2 feet) Fig.3.1.a WDM-3 meter gauge
 The second digit [power]
 D= Diesel
 C= DC traction
 A= AC traction YDM-3
 CA= Dual-power AC/DC traction
 B= Battery electric (rare) Fig.3.1.a YDM-3 Power
 The third digit [load]
 M= Mixed Traffic
 P= Passenger
 G= Goods ZDM-3
 U= Multiple Unit ( EMU/ DEMU)
 R= Railcar Fig.3.1.a ZDM-3 Load
 The Fourth Number [Version/Power]
The fourth slot in the class name will always be occupied by a number called
“Series“, denoting different things for different types of locomotives. This number
was initially intended to denote horsepower of the locomotive engine in multiples of

12. 7
1000 hp. However, this remained applicable only for WDM3X(A-F), WDG4 and
WDP4 diesels. For all remaining diesels including the non-BG ones and for all
electrics, the number denotes the version.
 The Fifth Letter [Subtype]
The fifth and in most cases the last letter is called a “Subtype” and is the most
confusing of all. It can be a letter or a number and may arbitrarily denote anything
from power rating to unique factors of the loco. For the WDM3 (A-F) diesels only,
the subclass annotation will be letters denoting incremental HP power in multiples of
100.
For all other locomotives, diesel or electric, the Subtype annotation can mean
anything, including major or minor modifications to original loco types, addition of
components, rebuilds or any other unique identification factors.

13. 8
Chapter-4: Diesel locomotive
4.1 Locomotive terminology
Locomotive – A vehicle that outputs energy and powers a train along the rails, the only
“live” part of the train. The coaches of a train are only pulled or pushed along the rails
by the locomotive. There are numerous types of locomotives, but most are powered by
either diesel fuel or electricity collected from overhead lines or a third rail. The
Locomotive and the engine are two different things.
Fig.4.1.1 Components of locomotive
Engine – Locomotives are popularly called “Engines”, though the engine is only a part
of the (diesel) locomotive, while electric locomotives do not have engines at all. The
engine is the most important part in diesel locomotives and supplies the power to turn
the wheels. The engine is also called a “Prime Mover”. These engines are huge, usually
having 16 Cylinders, 32 Valves and about 100,000 to 150,000 cc displacement.
Bogie – The Bogie is not, as many people wrongly say it to be, a railway passenger
vehicle unit. That is a coach, compartment, carriage or car. A bogie is a unit under a
coach or a locomotive body which houses the wheels, suspension etc. Usually there will
be two bogies for a coach and two or three for a locomotive with each bogie housing
four or six wheels.
Wheel Arrangement (WA) – The most common WA today is three wheels on either
side on two bogies (3 axles), 12 wheels in total and all axles powered, denoted Co-Co.
This is used in locomotives which haul heavy loads, which is 80% of all in India.
Driving Cab – The “Cockpit” of the locomotive, where the loco pilot (driver) and
assistant and any other sit and drive the loco. All controls are located here. The cluster
containing the controls to drive the locomotive is called a “Control Stand”.
Transmission – The medium used to send the power generated by the diesel engine to
the wheels. In modern locomotives, the diesel engine produces electric (AC) current
used to power traction motors which turn the wheels. Hence transmission is AC.

14. 9
Traction Motors – Electric motors that “actually” drive the wheels of the locomotive
and hence the train. These motors are directly connected to axles of the locomotive,
usually one per axle. They use the electric power generated by the generator/alternator
run by the diesel engine or from the transformers (electric locos) to output mechanical
power to turn the wheels and move the locomotive forward.
Long Hood Forward (LHF) – This is a driving mode for locomotives when the
locomotive is driven with the driving cab behind the longer Hood length of the
locomotive body. Visibility might be a problem here and many locomotives have speed
controls when driven in LHF.
Short Hood Forward (SHF) – This driving style is the opposite of LHF where the
locomotive is driven with the cabin towards the front of the locomotive, behind the
shorter “nose” of the loco. This is actually the “forward” operating position of the
locomotive, since the long hood is technically the rear of the loco with the radiator,
exhaust and all. Dual Cab locomotives do not have LHF/SHF.
4.2 Parts of locos
NOSE – It consist head light, sand box, resistance grid.
DRIVER’s CAB – It consists long hood, short hood, control stand, air brake control
stand, booster air pressure , indicating lube oil, pressure gauges, mechanical control &
electrical speedometer and load meter.
MAIN GENERATOR COMPARTMENT – It consists traction motor, excitation
generator, auxiliary generator, front traction motor blower and housed in this
compartment.
ENGINE ROOM - It consists after cooler, turbocharger governor, fuel injection pump,
fuel oil filters, lube oil filters, water pump, extension shaft, expressor spline coupling.
EXPRESSOR COMPARTMENT – It produces a vacuum compressed air which is
used for braking purpose, pump for hydraulic governor fuel booster pump & fuel booster
pump motor are also kept.
RADIATOR - Radiator fan, radiator panel, lube oil, right angle gear box, driving
radiator fan, eddy current clutch which converts right angle gear box to diesel engine’s
extension shaft.
GOVERNOR - Once a diesel engine is running, the engine speed is monitored and
controlled through a governor. The governor ensures that the engine speed stays high
enough to idle at the right speed and that the engine speed will not rise too high when
full power is demanded.

15. 10
Fig.4.2.1 Parts of locomotives
FUEL INJECTION - Ignition is a diesel engine is achieved by compressing air inside a
cylinder until it gets very hot (say 400°C, almost 800°F) and then injecting a fine spray
of fuel oil to cause a miniature explosion. The explosion forces down the piston in the
cylinder and this turns the crankshaft. To get the fine spray needed for successful
ignition the fuel has to be pumped into the cylinder at high pressure. The fuel pump is
operated by a cam driven off the engine. The fuel is pumped into an injector, which
gives the fine spray of fuel required in the cylinder for combustion.
RADIATOR AND RADIATOR FAN - The radiator works the same way as in an
automobile. Water is distributed around the engine block to keep the temperature within
the most efficient range for the engine. The water is cooled by passing it through a
radiator blown by a fan driven by the diesel engine.
4.3 Specification of YDM4
I. Diesel Engines
 6 Cylinder DLW 251D, 4-strock Turbo charged
 Injection system – through fuel injection pump, fuel injection tube &
Nozzle
 Governor – Woodward
 Compression ratio – 12.5 : 1
 Lube oil sump capacity – 530 Litres

16. 11
II. Transmission
 Electrical AC – DC
 6 Traction motor (3 in per bogie)
 Suspension – Axle hung/Nose suspension
 Gear ratio – 92 : 19 / 93 : 18
III. Brakes
Panel mounted IRAB-1 brake system Air, Hand, Dynamic brake
IV. Trunk
 Tri-mount Co-Co Steel Cast fabricated bogie
 Adhesion – 0.263
V. General characteristics
Table 4.3.1 General Characteristics
Installed power 1350 HP
Axle load 12 T
Gauge 1000 mm / cape gauge
Wheel arrangement Co-Co
Wheel diameter 965 mm
Height 3407 mm/ 3635 mm
Width 2730 mm/ 2742 mm
Overall length
(Over buffer beam)
13515 mm/ 14476 mm
Weight 72 T
Max tractive power 18.96 T
Max speed 96 k mph
Fuel tank capacity 3000 Litres
Locomotive control E – type Excitation control system / Microprocessor
control system also available

17. 12
Chapter-5: Diesel Engine
5.1 Diesel engine components and basic engine nomenclature
Fig.5.1.1 Locomotive Diesel engine
The locomotives are used I-shaped inline 6 cylinder 4 stroke Diesel engines. The diesel
engines are also known as “Compression ignition (CI) engines”.
Table 5.1.1 List of engine parts and material used
S. No. Name of the part Material used Method of
manufacture
1. Cylinder Cast iron, alloy steel Casting
2. Cylinder head Cast iron, aluminium alloy Casting, forming
3. Piston Cast iron, aluminium alloy Casting, forging
4. Piston rings Silicon cast iron Casting
5. Wrist or piston (gudgeon)
pin
Steel Forging
6. Valves Specially alloy steels Forging
7. Connecting rods Steel Forging
8. Crankshaft Alloy steel, SG iron Forging
9. Crankcase Aluminium alloy, steel, cast
iron
Casting
10. Cylinder liner Cast iron, nickel alloy steel Casting
11. Bearing White metal, leaded bronze Casting

18. 13
Fig. 5.1.2 Cut sectional view of Diesel engine
The standard terminology used in CI engines:
i) Cylinder bore (D): The nominal inner diameter of the working cylinder.
ii) Piston area (A): The area of a circle of diameter equal to the cylinder bore.
iii) Stroke (L): The nominal diameter through which a working piston moves
between two successive reversals of its direction of motion.
iv) Dead centre: The position of the working piston and the moving parts which are
mechanically connected to it at the moment when the direction of the piston
motion is reversed.
(a) Bottom Dead Centre (BDC)
(b) Top Dead Centre (TDC)

19. 14
v) Displacement volume or piston swept volume (Vs): The nominal volume
generated by the working piston when travelling from one dead centre to next
one, calculated as the product of area and stroke.
Vs = A*L
vi) Clearance volume (Vc): The nominal volume of the space on the combustion
side of the piston at TDC.
vii) Cylinder volume (V): The sum of piston swept volume and clearance volume.
V = Vs + Vc
viii) Compression ratio (CR or r): The numerical value of the cylinder volume
divided by the numerical value of the clearance volume.
Compression ratio (r) = V/Vc
5.2 Working of Diesel Engine
In the CI engine a high pressure fuel pump and an injector is provided to inject fuel into
combustion chamber. The ideal sequence of operation for the 4 stroke CI engine is as
follows:
1. Suction stroke: Only air is inducted during the suction stroke. During this stroke
intake valve is open and exhaust valve is closed.
2. Compression stroke: Both valves remain closed during compression stroke.
3. Expansion or power stroke: Fuel is injected in the beginning of the expansion
stroke. The rate of injection is such that the combustion maintains the pressure
constant. After the injection of fuel is over (i.e. after fuel cut off) the products of
combustion expand. Both valves remain closed during expansion stroke.
4. Exhaust stroke: The exhaust valve is open and the intake valve remains closed in the
exhaust stroke.
The typical valve timing diagram for a 4 stroke CI engine is as follows:
IVO up to 30o before TDC
IVC up to 50o after BDC
EVO about 45o before BDC
EVC about 30o after TDC
Injection about 15o before TDC

20. 15
Chapter-6: Expressor
6.1 Introduction
In Indian Railways, the trains normally work on vacuum brakes and the diesel locos on
air brakes. As such provision has been made on every diesel loco for both vacuum and
compressed air for operation of the system as a combination brake system for
simultaneous application on locomotive and train.
In ALCO locos the exhauster and the compressor are combined into one unit and it is
known as EXPRESSOR. The expressor is located at the free end of the engine block and
driven through the extension shaft attached to the engine crank shaft. The two are
coupled together by splined flexible coupling (Kopper's coupling). Naturally the
expressor crank shaft has eight speeds like the engine crank shaft and runs between 400
RPM to 1000 RPM range.
Fig. 6.1.1 Expressor
6.2 Construction
The expressor consists of the following components mainly;
(1) Crank case
(2) Crank shaft
(3) Four Nos. of exhauster cylinders with cylinder heads
(4) One low pressure compressor cylinder with cylinder head
(5) One high pressure cylinder with cylinder head

21. 16
(6) Six no. of pistons with connecting rods (including 1 LP, 1 HP and 4 Exhauster)
(7) Lube oil pump.
Each of two crank journals supports three connecting rods. The crankshaft is supported
at the both ends by double row ball bearings. Outside the ball bearings are located oil
seals to prevent the leakage of oil from inside the crank case and air from outside into it.
6.3 Working of Exhauster and Compressor
Exhauster:
Air from vacuum train pipe is drawn into the exhauster cylinders through the open inlet
valves in the cylinder heads during its suction stroke. Each of the exhauster cylinders
has one or two inlet valves and two discharge valves in the cylinder head.
The pressure differential between the available pressure in the vacuum train pipe and
inside the exhauster cylinder opens the inlet valve and air is drawn into the cylinder from
train pipe during suction stroke. In the next stroke of the piston the air is compressed and
forced out through the discharge valve while the inlet valve remains closed. The
differential air pressure also automatically opens or closes the discharge valves, the same
way as the inlet valves operate. This process of suction of air from the train pipe
continues to create required amount of vacuum and discharge the same air to
atmosphere.
Compressor:
The compressor is a two stage compressor with one low pressure cylinder and one high
pressure cylinder. During the first stage of compression it is done in the low pressure
cylinder where suction is through a wire mesh filter. After compression in the LP
cylinder air is delivered into the discharge manifold at a pressure of 30 / 35 PSI.
Workings of the inlet and exhaust valves are similar to that of exhauster which
automatically open or close under differential air pressure. For inter-cooling air is then
passed through a radiator known as inter-cooler. This is an air to air cooler where
compressed air passes through the element tubes and cool atmospheric air is blown on
the outside fins by a fan fitted on the expressor crank shaft. Cooling of air at this stage
increases the volumetric efficiency of air before it enters the high- pressure cylinder. A
safety valve known as inter cooler safety valve set at 60 PSI is provided after the inter
cooler as a protection against high pressure developing in the after cooler due to defect
of valves.
After the first stage of compression and after-cooling the air is again compressed in a
cylinder of smaller diameter to increase the pressure to 135-140 PSI in the same way.
This is the second stage of compression in the HP cylinder. Air again needs cooling
before it is finally sent to the air reservoir and this is done while the air passes through a
set of coiled tubes below the loco superstructure.

22. 17
Chapter-7: Turbo Supercharger
7.1 About Turbo Supercharge
1. It is used increase the amount of air pushed into cylinder.
2. Pressure of air is 3-6 kg/cm2.
3. It gives a 50% increase in engine power.
4. Advantage is that it gives more power with no increase in fuel cost because it uses
exhaust gas as driving power.
6. It also increase the air pressure,better ignition & efficiency.
7.2 CAUSES OF TURBO CHARGER
1. Intermediate casing, turbine.
2. casing, nozzle failure.
Fig 7.2.1 Turbo Super charger

23. 18
Chapter-8: Braking system in locos
8.1 Introduction
A brake is an appliance used to apply frictional resistance to a moving body to stop or
retard it by absorbing its kinetic energy. In general, in all types of motion, there is
always some amount of resistance which retards the motion and it sufficient to bring the
body to rest. However, the time taken and distance covered in this process is usually too
large. By providing brakes, the external resistance is considerably increased and the
period of retardation shortened.
Fig. 8.1.1 Schematic of air brake system
8.2 Types of brakes in locos
1) A-9 brake: - Brake application for Loco as well as formations.
2) SA-9 brake: - Brake Application for Loco alone.
3) Dynamic brake: - To decrease the speed of loco and train on sloping path.
4) Hand brake : -
5) Emergency brake
8.3 A-9 Braking system

24. 19
It is a vacuum brake system. It is pressure reducing, pressure maintaining and self-
lapping valve. It is provided on both control stands; it reduced main reservoir pressure 8-
10 kg/cm² to 5 kg/cm² and has 4 ports 30, 5, 1 and exhaust.
Its handle has 5 positions -
1. Release: - pressure to 5.0kg/cm2, Vacuum is about 55-60 cm.
2. Minimum reduction: - pressure in brake pipe= 4.5 kg/cm2, Vacuum =50-55 cm
3. Full service: - Brake pipe pressure = 3.5 kg/cm2, Vacuum =25-30 cm
4. Over reduction: - Brake pipe pressure = 2.5 kg/cm2, Vacuum =20 cm
5. Emergency: - Brake pipe pressure = 0.0kg/cm2, engine is in idle condition
8.4 SA-9 Braking system
It is an air brake system. It is a variable pressure-reducing valve, sends pilot air to C2
relay valve to charge brake cylinder for application and release of loco brake
independently. The outlet pressure can be varied from 0 to max (3.0 Kg / Cm2) by
moving its handle. Its handle has two distinct positions.
1. Application
2. Release
The output pressure is zero at release position and the pressure is max (3.0 kg / cm2) at
application position. The handle can be placed at any position between release and
application to have desired out let pressure (i.e. Brake cylinder pressure)
8.5 Dynamic Braking system
It is an electrical brake, used only when loco is in motion. During dynamic braking,
traction motor works as generator, hence retardation torque is developed on axle which
opposes the movement of wheel and speed of loco is reduced.
Advantages of dynamic braking-
1. No wear and tear in brake block and wheels.
2. Speed of train can be maintained constant on down gradient.
3. Train can be controlled easily without jerk.
4. Fuel saving.
5. To Maintain train punctuality.
Procedure of Applying Dynamic Brake –
1. Bring MH to idle position gradually.
2. Apply train brake by A9.
3. Bring MH on IDLE’ position and then SH kept on “Braking” position. After this MH
kept on “o” and then braking position and wait for some time, then move the master
handle slowly towards the ‘MAX’ positions of braking.
4. Keep watch on load meter.

25. 20
5. To release the dynamic brake, bring the MH slowly to “Braking” position and then
“o” position.
6. After waiting for some time, MH handle kept on “Idle” Position and then SH kept on
“Motoring” position.
Precautions to be taken During Dynamic Braking –
1. Operate the master handle smoothly.
2. Do not apply independent loco brakes during Dynamic Brake.
3. Do not apply emergency train brakes.
4. Do not apply dynamic brakes when BKBL is not working.
5. During dynamic braking if GR operates, don’t apply dynamic brakes.
6. If GFC is wedge do not use dynamic brake.
7. If the locomotive speed exceeds more than 90 km/h, braking current should not
exceed 600 amps.
8. If the speed of the locomotive is less than 90 km/h then maximum braking current is
limit up to 800 amps.
8.6 Hand Brake system
Hand brake is another kind of brake provided in the Driver’s cab. It consists of a gear
and handle arrangement directly connected to the brake cylinder to push the horse shoe
onto the wheel when encountering slipping surfaces. Hand brake is applied only one
wheel using a handle (fitted in the Driver’s cab acting as lever).
8.7 Emergency Braking system
There is an emergency brake valve which is provided on assistant driver’s side in cab,
which is being applied during emergency conditions. During its application BP pressure
is directly exhausted through its exhaust port and air brake is preformed through A-9
brake system.

26. 21
8.8 Advantage of Air Brake system over Vacuum Brake system
Table 8.8.1 Comparison of air brake system and vacuum brake system
S. No. Air brake system Vacuum brake system
1. Principle of working :-
The compressed air is used for
obtaining brake application. The brake
pipe and feed pipe run throughout the
length of the coach. Brake pipe and
feed pipe on consecutive coaches in
the train are coupled to one another by
means of respective hose couplings to
form a continuous air passage from the
locomotive to the rear end of the train.
The compressed air is supplied to the
brake pipe and feed pipe from the
locomotive. The magnitude of braking
force increases in steps with the
corresponding reduction in brake pipe
pressure and vice-versa.
Principle of working :-
The vacuum brake system
derives its brake force from the
atmospheric pressure acting on
the lower side of the piston in the
vacuum brake cylinder while a
vacuum is maintained above the
piston. The train pipe runs
throughout the length of the
coach and connected with
consecutive coaches by hose
coupling. The vacuum is created
in the train pipe and the vacuum
cylinder by the ejector or
exhauster mounted on the
locomotive.
2. Pressure :-
Effective cylinder pressure =
3.8kg/cm2
Feed pipe - 6kg/cm2
Brake pipe - 5kg/cm2
Pressure :-
Effective pressure on piston -
0.kg/cm2
Nominal vacuum on train pipe -
510mm.
3. Pipe diameter :-
Feed pipe - & 25 Bore
Brake pipe - & 25 Bore
Pipe diameter :-
Train pipe - & 50 Bore
4. Very Safe Needs additional precautions
5. Very good overall reliability Satisfactory overall reliability
6. Preparation time in departure yards
less than 40 minutes.
Preparation time in departure
yards up to 4 hours.
7. Low maintenance High maintenance

27. 22
Chapter-9: Bogie
9.1 Design priciples
A bogie is a structure underneath a railway vehicle body to which axles and wheels are
attached through bearings. The term “bogie” is used in British English, while a “wheel
truck” or simply “truck” is used in American English. The overall term is “running
gear”, which covers bogies as well as vehicles with two, or more axles without any
bogies. In this case, these axles are directly fitted to the vehicle body via guiding devices
and springs, and for very low speeds even without springs. Running gears serve a
number of purposes:
 Support of the rail vehicle body.
 Stability on both straight and curved tracks.
 Providing ride comfort by absorbing vibration, and minimizing centrifugal forces
when the train runs on curves at high-speed.
 Minimizing generation of track irregularities and rail abrasion
9.2 Wheel set arrangement classification
The wheel set arrangement classification is a systematic tool to sort railway vehicles by
position of the wheel sets (axles), bogies and connections of vehicle bodies. There are
several notations used to describe wheel set and wheel arrangements, which vary by
country. Within a given country, different notations may be employed for different kinds
of locomotives, such as electric and diesel. The UIC classification scheme is widely
used. It is provided by the International Union of Railways and laid down in the UIC’s
“Leaflet 650 – Standard designation of axle arrangement on locomotives and multiple
unit sets”.
 Upper-case letters designate a number of consecutive driving axles, starting at
“A” for a single axle. “C” thus indicates three consecutive pairs of driving
wheels.
 Numbers designate consecutive non-driving axles, starting with “1” for a single
axle.
 Lower-case “o” designates axles, which are individually driven by electric
traction motors in locomotives and multiple units.
 Prime sign “´” indicates that the axles are mounted on a bogie.

28. 23
Fig. 9.2.1 Coccus Bogie
Selection of practical examples:
 B´B´ two bogies or wheel assemblies under the unit. Each bogie has two powered
axles, connected by driving rods or gears.
 Bo´Bo´ each bogie has two individually driven powered axles (i.e. via traction
motors). 75% of all modern locomotives (as well as the power cars of self-
propelled trains) are configured as Bo´Bo´.
 Co´Co´ two bogies or wheel assemblies under the unit. Each bogie has three
individually-driven, powered axles (i.e., via traction motors).
 Bo´Bo´ + 2´2´ + 2´2´ multiple unit, first unit: two bogies, each bogie has two
individually-driven powered axles; second and third unit: two bogies, each bogie
with two non-powered axles.
 Bo´ 2´ Bo´ articulated vehicle: first and last bogie have two individually-driven
powered axles / middle bogie (Jacobs design) with two non-powered axles.
Fig. 9.2.2 Wheelset arrangement classification

29. 24
9.3 Spring
Primary springs:-
The primary springs connect the axlebox to the bogie frame. For higher speeds, a
secondary spring system connects the bogie frame to the vehicle body. The springs can
be designed as steel leaf or coil springs, as rubber springs or as air springs. The aim of
bogie springs is to reduce the forces and vibrations, to avoid derailment and to uncouple
vibration and noise between the wheel sets and the vehicle body. The primary spring acts
between the wheel set via the axle box bearing and the bogie frame. The secondary
spring is situated between the bogie frame and the vehicle body. Primary springs acting
on the axle react to vertical jounce and loads that arise longitudinally and laterally from
the influence of the rail track on the vehicle body. In addition, springs decouple
structure-borne noise. Enhanced bogie designs are based on different spring systems
acting in several directions and using materials such as steel and rubber.
Secondary springs:-
Secondary spring systems of enhanced bogie designs are a combination of air spring
bellows and the rubber-metal bearer spring, which supports the system, especially when
there is torsional strain and large horizontal excursions. The system also absorbs a
portion of the vertical deflection and acts as an emergency spring. An additional feature
of air springs is the constant leveling function that maintains the vehicle body at a
consistent height, regardless of whether it is full of passengers or empty.

30. 25
Chapter-10: Fuel oil system
10.1 Introduction
The fuel oil system is designed to supply fuel to the engine in correct quantity and at the
right time according to the engine requirements. The fuel oil system draws fuel from fuel
tank, filter the fuel, pressurization the fuel, and inject the fuel into the engine in correct
quantity in anatomist condition.
Fuel oil system consist of
1. Fuel feed system
2. Fuel injection system
10.2 Fuel feed system
Fig.10.2.1 Fuel injection system
Fuel is drawn from the fuel oil tank through a suction strainer by the fuel pump. The
strainer separates foreign particles from the fuel oil, and protects the fuel pump. The
pump is designed to supply adequate quantity of fuel to the engine at various speeds and
load conditions.
Fuel then goes to primary fuel filter. This primary filter is provided with a 30-PSI bypass
valve with sight glass, which should be normally empty. Whenever the primary filter is
Choked/clogged and the pressure difference reaches 30 PSI this bye-pass value open

31. 26
allowing the fuel oil directly to the system, which can be noticed by the flow of bypass
fuel in the sight glass. Under such cases the primary filter element is changed. The fuel
then passes to 02 engine mounted secondary filters, which are of spin-on type.
Secondary fuel filters are also provided with a bypass value, which is set at 60 PSI.
Whenever the filters are choked/clogged and the pressure difference across the
secondary filters reaches 60 PSI, this bye-pass valve opens and diverts the fuel oil back
to fuel tank, avoiding damage to fuel injectors due to unfiltered fuel oil. A bypass sight
glass is also provided to indicate the condition of the fuel secondary filters and the sight
glass should be normally empty. From the secondary filters the fuel oil is supplied to all
unit injectors through fuel supply manifolds located inside the top deck on the both
banks. The governor controls the quantity of fuel to be injected through the injectors to
the engine. At the end of the fuel supply manifolds, a regulating valve with a sight glass
is provided which is set to 10 PSI. The regulating valve ensures constant fuel supply to
all unit injector in all working conditions. If the system is working properly the sight
glass should indicate clear and clean fuel oil flow all the time. Air bubbles, interrupted
fuel flow or no fuel flow in the return sight glass indicates problem in the fuel feed
system.
10.3 Fuel injection system
Fig. 10.3.1 Fuel injector

32. 27
Fuel supplied by the fuel feed system is always available at all the unit fuel injectors.
The fuel oil available at each injector are to be pressurized to very high pressure, timed
and to be injected in the cylinder in atomized form. The timing of each unit injector is
decided by the camshaft and the fuel is pressurized by the in-built fuel injection pump
which is operated by individual cam lobe of the cam shaft. The quantity of fuel to be
injected will be regulated and controlled by engine mounted wood word governor
according to the notch and load conditions. The governor operates fuel control shaft,
linkage mechanism and fuel racks. The individual fuel injector nozzle does the
itemization of the fuel to be injected in the cylinder.

33. 28
Chapter-11: Water cooling system
11.1 Description
Engine cooling water system is a closed loop pressurized water cooling system. The
water cooling system cools – All the engine cylinder liners, cylinder heads, after cooler,
lube oil cooler and compressor.
Fig. 11.1.1 Water cooling system
In the water cooling system, there are 02 nos. engine mounted water pumps (centrifugal
type). The water pump receives water from the radiator through lube oil cooler. Water
from the water pump is sent to the two (left and right Bank) water main header (also
called water inlet manifold). From the water main header water enter to all the cylinder
liner jackets through water jumper. After cooling the cylinder liners water enter in the
cylinder head through 12 holes which are matched to cylinder liner with “O” rings and
cool the combustion chamber of the cylinder head. Outlet water from each cylinder head
goes to the return header (also called water outlet manifold) which carries water to the
radiator. Each water main header is connected at the rear end from where a water pipe
line carries water to cool the after cooler. Water from the after cooler goes to water
return header and through water return header to radiator. A water pipe line from the
water pump carry water to compressor to cool the compressor liners, cylinder head,
valves and the compressed air inside the inter cooler. Air compressor cooling is done

34. 29
whenever engine is running. The radiators are located in a hatch at the top of the long
hood end of the locomotive. The hatch contains the radiator assemblies, which are
grouped in two banks. Each radiator bank consists of two quad length radiator core
assemblies, bolted end-to-end. Headers are mounted on the radiator core to form the inlet
and outlet ends of the radiator assembly, a bypass line is provided between the inlet and
outlet lines in order to reduce velocity in the radiator tubes. Two 8-blade 52” cooling
fans, which operate independently, are located under the radiators in the long hood car
body structure. They are numbered 1, and 2, with the No. 1 fan being closest to the
driver cab. The water pump inlet side is connected to an expansion tank for makeup
water in the water system. The expansion tank is located in the equipment rack.
11.2 Cooling system predestination
The cooling system is pressurized to raise the boiling point of cooling water. This in turn
permits higher engine operating temperatures, with a minimum loss of coolant due to
pressurization and also ensures a uniform water flow and minimizes the possibility of
water pump capitation during transient high temperature conditions. A pressure cap,
which is located on the water tank filling pipe, opens at approximately 20 PSI. It
prevents the damages of cooling system components by relieving excessive pressure
from the system. The pressure cap is equipped with a handle which helps installing and
removing of the cap. The most important function of the pressure cap handle is to release
pressure developed in the water system before removing the pressure cap.

35. 30
References
1. Mathur, M.L. and Sharma R.P., Internal Combustion Engine, 8/e, Dhanpat Rai Publications,
1976.
2. Rattan, S.S., Theory of Machines, 4/e, McGraw Hill, 1993.
3. http://www.dlw.indianrailways.gov.in/works/uploads/File/YDM4.pdf
4. http://www.nwr.indianrailways.gov.in
5. http://www.diesellocoshed.com
6. http://www.railway-technical.com/trains/rolling-stock-index-I/diesel-locomotive/
7. http://www.irimee.indianrailways.gov.in/instt/uploads/files/1434534006809-
AIR%20BRAKE%20IRAB-1.pdf
8. http://indianrail.wikia.com
9. http://24coaches.com/locomotive-working-india/