2. 2
ACKNOWLEDGEMENT
I take this opportunity my sincere thanks and deep gratitude to
R.P SINGH (HEAD OF MECHANICAL DEPARTMENT) all these
people who extended their whole hearted co-operation and helped me in
completing this project successfully.
First of all I would like to thanks all the S.S.E. and J.E. of the
all the sections for creating oppurtunities to undertake me in this esteemed
organization. Special thanks to all the department for all the help and
guidance extended to me by them in every stage during my training. His
inspiring suggestions and timely guidance enabled me to perceive the
various aspects of the project in the new light.
In all I found a congenial work environment in DIESEL
LOCOMOTIVE WORKSHOP, GONDA and this completion of the
project will mark a new beginning for me in the coming days.
SUBMITTED BY:
SHIVENDRA SINGH
ROLL NO: 1421640190
B.Tech (MECHANICAL)
IIMT COLLEGE OF ENGINEERING
3. 3
CONTENTS
INTRODUCTION OF INDIAN RAILWAY…………………………………4
DIESEL LOCOMOTIVE SHED . ……………………...…………………... 5
DIESEL ELECTRIC LOCOMOTIVE…………….......…………………... 9
FUEL SECTION………………………………...……...…………. ……….11
LUE OIL CONTROLSECTION……......................…………................. 12
TURBOSUPER CHARGER………………………...………….................13
FUEL OIL PUMP……...………………………………….……… ………...17
BOGIE……...……………………………………………………..…………19
EXPRESSOR/COMPRESSSOR……...……………………....................22
AIR BRAKE……...…………………………………………….…...……….24
TRACTIONMOTER……...………………………………………………... 25
GENERATOR……...………….………………..…………………………..26
POWER PACK……...………….…………………….….………………….27
CROSS HEAD……...………………………………..…………………… 30
FAILURE ANALYSIS……...…………………………………...………….. 32
YEARLY MECHANICAL TESTING……...……………….……………... 36
PROJECT STUDY__ TO STUDY ABOUT THE DIESEL BOGIE…
………………………………………….................……………...…………38
4. 4
INTRODUCTION
OF
INDIAN RAILWAY
Indian Railways is the state-owned railway company ofIndia. It comes
under the Ministry of Railways. Indian Railways has one of the largest and busiest
rail networks in the world, transporting over 18 million passengers and more than 2
million tonnes of freight daily. Its revenue is Rs.107.66 billion. It is the world's
largest commercial employer, with more than 1.4 million employees. It operates rail
transport on 6,909 stations over a total route length of more than
63,327 kilometers(39,350 miles).The fleet of Indian railway includes over 200,000
(freight) wagons, 50,000 coaches and 8,000 locomotives. It also owns locomotive
and coach production facilities. It was founded in 1853 under the East India
Company.
Indian Railways is administered by the Railway Board. Indian
Railways is divided into 16 zones. Each zone railway is made up ofa certain number
of divisions. There are a total of sixty-seven divisions.It also operates the Kolkata
metro. There are six manufacturing plants of the Indian Railways. The total length
of track used by Indian Railways is about 108,805 km (67,608 mi) while the total
route length of the network is 63,465 km (39,435 mi). About 40% of the total track
kilometer is electrified & almost all electrified sections use 25,000 V AC. Indian
railways uses four rail track gauges
Indian Railways operates about 9,000 passenger trains and transports
18 million passengers daily .Indian Railways makes 70% of its revenues and most
ofits profits from the freight sector, and uses these profits to cross-subsidies the loss-
making passenger sector. TheRajdhani Express and Shatabdi Express are the fastest
trains of India.
5. 5
DIESEL LOCOMOTIVE SHED
GONDA
GONDA DIESELSHED
Diesel locomotive shed is an industrial-technical setup, where repair and
maintenance works of diesel locomotives is carried out, so as to keep the loco
working properly. It contributes to increase the operational life of diesel locomotives
and tries to minimize the line failures. The technical manpower of a shed also
increases the efficiency of the loco and remedies the failures of loco.
The shed consists of the infrastructure to berth, dismantle, repair and test the loco
and subsystems. Theshed working is heavily based onthe manual methods of doing
6. 6
the maintenance job and very less automation processesareused in sheds, especially
in India.
The diesel shed usually has:-
Berths and platforms for loco maintenance.
Pits for under frame maintenance
Heavy lift cranes and lifting jacks
Fuel storage and lube oil storage, water treatment plant and testing
labs etc.
Sub-assembly overhauling and repairing sections
Machine shop and welding facilities.
DIESEL SHED, GONDA of NORTHERN RAILWAY is located in GONDAThe
shed was established on 22nd April 1984. It was initially planned to home 75
locomotives. The shed cater the needs of Northern railway. This shed mainly
provides locomotive to run the mail, goods and passenger services. No doubt the
reliability, safety through preventive and predictive maintenance is high priority of
the shed. To meet out the quality standard shed has taken various steps and obtaining
of the ISO-9001-200O& ISO 14001 OHSAS CERTIFICATIONis among of them.
The Diesel Shed is equipped with modern machines and plant required for
Maintenance of Diesel Locomotives and has an attached store depot. To provide
pollution free atmosphere, Diesel Shed has constructed Effluent Treatment Plant.
The morale of supervisors and staff of the shed is very high and whole shed works
like a well-knit team.
7. 7
a) OVER VIEW
Inception 22nd April1857
Present Holding 147 Locomotives
19 WDM2
37 WDM3A
08 WDM3D
11 WDG3A
46 WDP1
26 WDP3A
Accreditation ISO-9001-2000 & ISO
14001
Covered area of shed 10858 SQ. MTR
Total Area of shed 1, 10,000 SQ. MTR
Staff strength sanction – 1357
On roll - 1201
Berthing capacity 17 locomotives
8. 8
(b) CLASSIFICATION
1. Standard “Gauge” designations and dimensions:-
W = Broad gauge (1.67 m)
Y = Medium gauge ( 1 m)
Z = Narrow gauge ( 0.762 m)
N = Narrow gauge ( 0.610 m)
2. “ Type of Traction” designations:-
D = Diesel-electric traction
C = DC traction
A = AC traction
CA=Dual power AC/DC traction
3. The “ type of load” or “Service” designations:-
M= Mixed service
P = Passenger
G= Goods
S = Shunting
4. “ Horse power ” designations from June 2002 (except WDP-1 & WDM-2
LOCOS)
‘ 3 ’ For 3000 horsepower
‘ 4 ’ For 4000 horsepower
‘ 5 ’ For 5000 horsepower
‘ A ’ For extra 100 horsepower
‘B’ For extra 200 horsepower and so on
.
Hence ‘WDM-3A’ indicates a broad gauge loco with diesel-electric
traction. It is for mixed services and has 3100 horsepower.
9. 9
DIESEL ELECTRIC LOCOMOTIVE
PARTS OF THE LOCOMOTIVE( FIG 2)
SAND BOX
RADIATOR
RADIATOR FAN
TURBO SUPERCHARGER
BOGIE(2 SETS)(3AXLE OR 2 AXLE)
10. 10
FUEL TANK
AIR RESERVOIERS
POWER PACK
DYNAMO WITH ALTRNATOR
BATTERIES
DRIVER CABIN
WHEEL ASSEMBLY
DISC
BLOWER
TRACTON MOTER
TRUCK
GEAR AND PENION ASSSEMBLY
CYLINDER HEAD
CROSS HEAD
FUEL INJECTION PUMP
BATTERIES (8 OF 8.68 VOLTS)
FUEL TANK
AFTER COOLING CORE
JUNCTION BOX
11. 11
FUEL SECTION
FUEL TANK FOR LOCO (FIG 3)
The section is concern with receiving, storage and
refilling of diesel and lube oil. It has 3 large storage tanks and one underground
tank for diesel storage which have a combined storage capacity of 10,60, 000
liters. This stockis enough to end for 15-16 days The fuel is supplied by truck
from IOC - PANIPAT REFINERY each truck diesel sample is treated in diesel
lab and after it in unloaded. Sample check is necessary to avoid water, kerosene
mixing diesel. Two fuel filling points are established near the control room
It also handles the Cardiam compound , lube oil. diesel is only for loco use if
the diesel samples are not according to the standard , the delivery of the fuel
is rejected. Viscosity of lube oil should be 100-1435 CST. Water mixing reduces the
viscosity.
Statement of diesel storage and received is made after every 10 days and the report
is send to the Division headquarter. The record of each truck, wagons etc are
included in it. The record of issued oil is also sending to headquarter. After each 4
months. A survey is conducted by high level team about the storage, records etc.
0.1% of total stored fuel oil is given for handling losses by the HQ. The test reports
of diesel includes the type of diesel ( high speed diesel- Euro-3 with 0.035 % S),
reason for test, inspection lot no, store tank no, batch no. etc.
12. 12
LUBE OIL CONTROL SYSTEM
It controls and regulates the complete movement, schedules, duty of
each loco of the shed. Division level communications and contacts with each loco
on the line are also handled by the control room. Full record of loco fleet, failures,
duty, overdue and availability of locos are kept by the control room. It applies the
outage target of loco for the shed, as decided by the HQ. It decides the locomotives
mail and goods link that which loco will be deployed on which train. It operates 116
Mail and 11Goods link from the shed locos. For0-0 outage total 127 loco should be
on line.
The schedule of duty, trains and link is decided by the controlroom according to the
type of trains. If the loco does not return on scheduled time in the shed then the loco
is termed as ‘ over due’ and control room can use the loco of another shed if that is
available.
The lube oil consumptionis also calculatedbythe controlroomfor
eachloco:- Lube Oil Consumption (LOC) = Lube oil consumed in liters/ total
kms travelled ×100
13. 13
TURBO SUPERCHARGER
TURBOSUPERCHARGER(FIG 4)
The diesel engine produces mechanical energy by converting heat energy derived
from burning of fuel inside the cylinder. Forefficient burning of fuel, availability of
sufficient air in proper ratio is a prerequisite.
In a naturally aspirated engine, during the suction stroke, air is being sucked into the
cylinder from the atmosphere. The volume of air thus drawn into the cylinder
through restricted inlet valve passage, within a limited time would also be limited
and at a pressure slightly less than the atmosphere. The availability of less quantity
of air of low density inside the cylinder would limit the scope of burning of fuel.
Hence mechanical power produced in the cylinder is also limited.
An improvement in the naturally aspirated engines is the super-charged or pressure
charged engines. During the suction stroke, pressurised stroke of high density is
being charged into the cylinder through the opensuction valve. Air of higher density
containing more oxygen will make it possible to inject more fuel into the same size
of cylinders and produce more power, by effectively burning it.
14. 14
A turbocharger, or turbo, is a gas compresser used for forced-induction of an
internal combustionengine. Like a supercharger, the purposeof a turbocharger is to
increase the density of air entering the engine to create more power. However, a
turbocharger differs in that the compressor is powered by a turbine driven by the
engine's own exhaust gases.
(a)TURBO SUPERCHARGER AND ITS WORKING
PRINCIPLE
The exhaust gas discharge from all the cylinders accumulate in the common
exhaust manifold at the end of which, turbo- supercharger is fitted. The gas under
pressure there after enters the turbo- supercharger through the torpedo shaped bell
mouth connector and then passes through the fixed nozzle ring. Then it is directed
on the turbine blades at increased pressureand at the most suitable angle to achieve
rotary motion of the turbine at maximum efficiency. After rotating the turbine, the
exhaust gas goes out to the atmosphere through the exhaust chimney. The turbine
has a centrifugal blower mounted at the other end of the same shaft and the rotation
of the turbine drives the blower at the same speed. The blower connected to the
atmosphere through a set of oil bath filters, sucks air from atmosphere, and delivers
at higher velocity. The air then passes through the diffuser inside the turbo-
supercharger, where the velocity is diffused to increase the pressure of air before it
is delivered from the turbo- supercharger.
Pressurising air increases its density, but due to compressionheat develops. It causes
expansion and reduces the density. This effects supply of high-density air to the
engine. To take care of this, air is passed through a heat exchanger known as after
cooler. The after cooler is a radiator, where cooling water of lower temperature is
circulated through the tubes and around the tubes air passes. The heat in the air is
thus transferred to the cooling water and air regains its lost density. From the after
cooler air goes to a common inlet manifold connected to each cylinder head. In the
suction stroke as soon as the inlet valve opens the booster air of higher pressure
density rushes into the cylinder completing the process of super charging.
15. 15
The engine initially starts as naturally aspirated engine. With the increased quantity
of fuel injection increases the exhaust gas pressure on the turbine. Thus the self-
adjusting system maintains a proper air and fuel ratio under all speed and load
conditions of the engine on its own. The maximum rotational speed of the turbine is
18000/22000 rpm for the Turbo supercharger and creates max. Of 1.8 kg/cm2 air
pressure in air manifold of diesel engine, known as Booster Air Pressure (BAP).
Low booster pressure causes black smoke due to incomplete combustion of fuel.
High exhaust gas temperature due to after burning of fuel may result in considerable
damage to the turbo supercharger and other component in the engine.
(b)MAIN COMPONENTS OF TURBO-SUPERCHARGER
Turbo- supercharger consists of following main components.
Gas inlet casing.
Turbine casing.
Intermediate casing
Blower casing with diffuser
Rotorassembly with turbine and rotor on the same shaft.
16. 16
(c)ROTOR ASSEMBLY
The rotor assembly consists of rotor shaft, rotor blades, thrust collar,
impeller, inducer, centre studs, nosepiece, locknut etc. assembled together. The rotor
blades are fitted into fir tree slots, and locked by tab lock washers. This is a
dynamically balanced component, as this has a very high rotational speed.
TYPE POWER COOLING
1.ALCO 2600HP Water cooled
2.ABB TPL61 3100HP Air cooled
3.HISPANO SUIZA HS 5800 NG 3100HP Air cooled
4. GE 7S1716 3100HP Water cooled
5. NAPIER NA-295 2300,2600&3100HP Water cooled
6. ABB VTC 304 2300,2600&3100HP Water cooled
17. 17
FUEL OIL PUMP
All locomotive have individual fuel oil system. The fuel oil system is designed
to introduce fuel oil into the engine cylinders at the correcttime, at correctpressure,
at correct quantity and correctly atomized . The system injects into the cylinder
correctly metered amount of fuel in highly atomised form. High pressure of fuel is
required to lift the nozzle valve and for better penetration offuel into the combustion
chamber. High pressure also helps in proper atomisation so that the small droplets
come in better contactwith the compressed air in the combustion chamber, resulting
in better combustion. Metering of fuel quantity is important because the locomotive
engine is a variable speed and variable load engine with variable requirement of fuel.
Time of fuel injection is also important for better combustion.
(a)FUEL OIL SYSTEM
The fuel oil systemconsists of two integrated systems. Theseare-
FUEL INJECTIONPUMP (F.I.P).
FUEL INJECTIONSYSTEM.
18. 18
(b)FUEL INJECTION PUMP
It is a constantstroke plunger type pump with variable quantity of fuel delivery
to suit the demands of the engine. The fuel cam controls the pumping stroke of the
plunger. The length of the stroke of the plunger and the time of the stroke is
dependent on the cam angle and cam profile, and the plunger spring controls the
return stroke of the plunger. The plunger moves inside the barrel, which has very
close tolerances with the plunger. When the plunger reaches to the BDC, spill ports
in the barrel, which are connected to the fuel feed system, open up. Oil then fills up
the empty spaceinside the barrel. At the correcttime in the diesel cycle, the fuel cam
pushes the plunger forward, and the moving plunger covers the spill ports. Thus, the
oil trapped in the barrel is forced out through the delivery valve to be injected into
the combustion chamber through the injection nozzle. The plunger has two identical
helical grooves or helix cut at the top edge with the relief slot. At the bottom of the
plunger, there is a lug to fit into the slot of the control sleeve. When the rotation of
the engine moves the camshaft, the fuel cam moves the plunger to make the upward
stroke.
FUEL INJECTION PUMP(FIG 5)
19. 19
BOGIE
BOGIE(FIG 6)
A bogie is a wheeled wagon or trolley. In mechanics terms, a bogie
is a chassis or framework carrying wheels, attached to a vehicle. It can be fixed
in place, as on a cargo truck, mounted on a swivel, as on a railway carriage or
locomotive, or sprung as in the suspension of a caterpillar tracked vehicle.
Bogies serve a number of purposes:-
To support the rail vehicle body
To run stably on both straight and curved track
To ensureridecomfortbyabsorbingvibration,and minimizing centrifugalforces
when the train runs on curves at high speed.
To minimize generation of track irregularities and rail abrasion.
Usually two bogies are fitted to each carriage, wagon or locomotive, one at each
end.
20. 20
(a) KEY COMPONENTS OF A BOGIE
The bogie frame itself.
Suspensionto absorbshocks between thebogieframeand therail vehicle body.
Common types are coil springs, or rubber airbags.
At least two wheelset, composed of axle with a bearings and wheel at each end.
Axle box suspension to absorb shocks between the axle bearings and the bogie
frame. The axle box suspension usually consists of a spring between the bogie
frame and axle bearings to permit up and down movement, and sliders to
prevent lateral movement. A more modern design uses solid rubber springs.
Brake equipment:-Brake shoes are used that are pressed against the tread of
the wheels.
Traction motors for transmission on each axle.
(b)CLASSIFICATION OF BOGIE
21. 21
Bogie is classified into the various types described below according to their
configuration in terms of the number of axle, and the design and structure of the
suspension. Accordingto UIC classificationtwo types of bogie in Indian Railway are:-
Bo-Bo
Co-Co
CO-CO & BO-BO BOGIE(FIG 7)
A Bo-Bo is a locomotive with two independent four-wheeled bogies with all axles
powered by individual traction motors. Bo-Bos are mostly suited to express
passenger or medium-sized locomotives.
Co-Co is a codefor a locomotive wheel arrangement with two six-wheeled bogies
with all axles powered, with a separate motor per axle. Co-Cos is most suited to
freight work as the extra wheels give them good adhesion. They are also popular
because the greater number of axles results in a lower axle load to the tracK
22. 22
EXPRESSOR / COMPRESSOR
EXPRESSOR(FIG 8)
In Indian Railways, the trains normally work on vacuum brakes and the diesel
locos on air brakes. As suchprovision 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 compressorare combined into one unit and
it is known as EXPRESSOR. It creates 23" of vacuum in the train pipe and 140 PSI
air pressure in the reservoir for operating the brake system and use in the control
system etc.
The expressoris located at the free end ofthe engine blockand driven through the
extension shaft attached to the engine crank shaft. The two are coupled together by
fast coupling (Kopper's coupling). Naturally the expressor crank shaft has eight
speeds like the engine crank shaft. There are two types of expressor are, 6CD,4UC
& 6CD,3UC. In 6CD,4UC expressor there are six cylinder and four exhauster
whereas 6CD,3UC contain six cylinder and three exhauster.
23. 23
(a)COMPRESSOR
The compressoris a two stage compressorwith 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 compressionin 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. Forinter-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 coolatmospheric air is blown on the out side fins by a fan
fitted on the expressorcrank 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 compressionand 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 after cooler.
24. 24
AIR BRAKE SYSTEM
AIR BRAKE(FIG 9)
An air brake is a conveyance braking system actuated by
compressed air. Modern trains rely upon a fail preventive air brake system that is
based upon a design patented by George Westinghouse on March 5,1872. In the air
brake's simplest form, called the straight air system, compressed air pushes on a
piston in a cylinder. The piston is connected through mechanical linkage to brake
shoes that can rub on the train wheels, using the resulting friction to slow the train.
(a)AIR BRAKE SYSTEM OPERATION
The compressor in the locomotive produces the air supplied to the system. It is
stored in the main reservoir. Regulated pressure of 6 kg/cm2 flows to the feed pipe
through feed valve and 5-kg/cm2 pressure by driver’s brake valve to the brake pipe.
The feed pipe through check valve charges air reservoir via isolating cockand also
by brake pipe through distributor valve. The brake pipe pressure controls the
distributor valves of all the coaches/wagons which in turn control the flow of
compressed air from Air reservoir to break cylinder in application and from brake
cylinder to atmosphere in release.
25. 25
TRACTION MOTER
TRACTION MOTER(FIG 10)
Since the diesel-electric locomotive uses electric transmission, traction motors are
provided on the axles to give the final drive. These motors where the traditionally
DC but the development of modern power and control electronics has led to the
introduction of 3-phase AC motors. There are between four & six motors on most
diesel electric locomotives. A modern AC motors with air blowing can provide up
to 1000hp
26. 26
GENERATOR
This giant engine is hooked up to an equally impressive generator. It
is about 6 feet (1.8m) in diameter and weights about 17,700 pounds (8029kg). at
peak power this generator makes enough electricity to power a neighborhood of
about 1,000 houses.
So, where does all the power go? It goes into six, massive electric motors located
in the bogies.The engine rotates the crank shaft at up to 1000rpm and this drivesthe
various items need to power the locomotive. As the transmission is electric the
engine is used as the power sourcefor the electricity generator or alternator.
(a)MAIN ALTERNATOR
The diesel engine drives the main alternator which provides the
power to move the train. The alternator generator AC electricity which is used to
provide for traction motors mounts of the axles of the bogies. In older locomotives,
the alternator was a DC machine, called a generator. It producedirect current which
was used to provide power for DC traction motor. Many of these machines are still
in regular use. the next development was the replacement of the generator by the
alternator but still using DC traction motor. The AC output is rectified to give the
DC required for the motors.
(b)AUXILIARY ALTERNATORS
Locomotives used are equipped with an auxiliary alternators. This
provide AC power for lighting, air conditioning, etc. on the train. The output is
transmitted on the train through an auxiliary power line. The output from the main
alternator is AC but it can be used in locomotive with either DC or AC traction
motors. DC motors where the traditional type use for many years but, AC motors
have become standard new locomotives. They are cheaper to build and cost less to
maintain and to convert the AC output from the main alternator to DC, rectifiers are
required. If the motors are DC, the output from the rectifiers is used directly.
27. 27
Power Pack Section
FIG OF POWER PACK(FIG 11)
The work of the power pack is to do the fitting work of the head on the loco. They
take out head from the engine and assembled it again on the loco. In the power pack
section the assembly of piston and connecting rod is done. The thorough checking
of piston is done in this section. The piston is send for zyglo test then it is checked
for all the clearances. It is checked whether the piston is seizing or not.
There are two types ofpiston used modified and unmodified. In modified pistonand
pistonhead is made up ofsteel, the pistonskirt is made up ofaluminium. Unmodified
piston is totally made up of steel only. The weight of the assembly is of 90kg. There
are generally 5 rings used in the cylinder, first 3 are compressionring next 2 are oil
rings. The first one is made up of steel and has square face. The second one is also
of steel and has tapered face. The third one is of C.I. and is fuel efficient taper face.
The fourth and fifth are also of C.I. and are called oil scrapper rings.
(a) PARTS OF THE POWER PACK
28. 28
EXHAUST MANIFOLD
WATER CHANNEL
PGEV GOVERNOR
CRANK CASE MOTER
CYLINDER (MAX. 16 CYLINDER)
PISTON
FUEL OIL INJECTOR
ROCKER ARM
YOKE
LUBE OIL HEADER PIPE
L PIPE
F PIPE
S PIPE
CAM SHAFT
CRANK SHAFT
CROSS HEAD
FUEL INJECTION PUMP
CROSS PIPE
FIP COVER
FUEL OIL BENZO
LUBE OIL SUMP
GEAR CASE
CYLINDER HEAD
29. 29
INLET & EXHAUST VAULVE
TURBO SUPER CHARGER
AFTER COOLING CORE
OVER SPEED TRIP
HOUSING
OIL SLEEVE RING
WATER PUMP
LUBE OIL PUMP
OIL SLEEVE
DRAINE PIPE
FUEL CONTROOLING SHAFT
CROSS HEAD
FIG OF CROSS HEAD(FIG 12)
30. 30
The cylinder head is held on to the cylinder liner by seven hold down
studs or bolts provided on the cylinder block. It is subjected to high shockstress and
combustion temperature at the lower face, which forms a part of combustion
chamber. It is a complicated casting where cooling passages are cored for holding
water for cooling the cylinder head. In addition to this provision is made for
providing passage of inlet air and exhaust gas. Further, space has been provided for
holding fuel injection nozzles, valve guides and valve seat inserts also.
(a)COMPONENTS OF CYLINDER HEAD
In cylinder heads valve seat inserts with lock rings are used as
replaceable wearing part. The inserts are made of stellite or weltite. To provide
interference fit, inserts are frozen in ice and cylinder head is heated to bring about a
temperature differential of 250F and the insert is pushed into recess in cylinder
head. The valve seat inserts are ground to an angle of 44.5 whereas the valve is
ground to 45 to ensure line contact. (In the latest engines the inlet valves are ground
at 30° and seats are ground at 29.5°). Each cylinder has 2 exhaust and 2 inlet valves
of 2.85" in dia. The valves have stem of alloy steel and valve head of austenitic
stainless steel, butt-welded together into a composite unit. The valve head material
being austenitic steel has high level of stretch resistance and is capable of hardening
above Rockwell- 34 to resist deformation due to continuous pounding action.
The valve guides are interference fit to the cylinder head with an interference of
0.0008" to 0.0018". After attention to the cylinder heads the same is hydraulically
tested at 70 psi and 190F. The fitment of cylinder heads is done in ALCO engines
with a torque value of 550 Ft.lbs. The cylinder head is a metal-to-metal joint on to
cylinder.
ALCO 251+ cylinder heads are the latest generation cylinder heads, used in updated
engines, with the following feature:
Fire deck thickness reduced for better heat transmission.
Middle deck modified by increasing number of ribs (supports) to increase its
mechanical strength. The flying buttress fashion of middle deck improves the
flow pattern of water eliminating water stagnation at the corners inside cylinder
head.
Water holding capacity increased by increasing number of cores (14 instead of
11)
31. 31
Use of frost core plugs instead of threaded plugs, arrest tendency of leakage.
Made lighter by 8 kgs (Al spacer is used to make good the gap between rubber
grommet and cylinder head.)
Retaining rings of valve seat inserts eliminated.
BENEFITS
Better heat dissipation
Failure reduced by reducing crack and eliminating sagging effect of fire deck
area.
FAILURE ANALYSIS
32. 32
TESTING ACHINE(FIG 13)
A part or assembly is said to have failed under one of the three
conditions:- When it becomes completely inoperable-occurs when the component
breaks into two or more pieces.When it is still inoperable but is no longer able to
perform intended function satisfactorily- due to wearing and minor damages.
When serious deterioration has made it unreliable or unsafe for
continuous use, thus necessitating its complete removal from service for repair or
replacement-due to presence of cracks such as thermal cracks, fatigue crack,
hydrogen flaking.
In this section we will study about:-
Metallurgical lab.
Ultrasonic test
Zyglo test
RDP test.
(a)METALLURGICAL LAB
33. 33
Metallurgical lab. concern with the study of material composition
and its properties. Specimens are checked for its desired composition. In this section
various tests are conducted like hardness test, composition test e.g determination of
percentage of carbon, swelling test etc.
Function of some of the metal is tabulated in table below :-
S.No. Compound Function
1. Phosphorous Increase the fluidity property
2. Graphite Increase machinability
3. Cementide Increase hardness
4. Chromium Used for corrosion prevention
5. Nickel Used for heat resistance
6. Nitride rubber Oil resistance in touch of ‘O’ ring
7. Neoprene Air resistance & oil resistance in fast coupling
in rubber block.
8. Silicon Heat resistance and wear resistance (upto 600
ºC ) use at top and bottom pore of liner.
(b)ULTRASONIC TESTING
In ultrasonic testing, very short ultrasonic pulse-waves with center
frequencies ranging from 0.1-15 MHz and occasionally up to 50 MHz are launched
into materials to detect internal flaws or to characterize materials.
Ultrasonic testing is often performed on steel and other metals and alloys, though it
can also be used on concrete, wood and composites, albeit with less resolution. It is
a form of non-destructive testing.
(c)ZYGLO TEST
34. 34
The zyglo test is a nondestructive testing (NTD) method that helps to
locate and idetify surface defects in order to screen out potential failure-producing
defects. Itis quick and accqurate process for locating surface flaws such as shrinkage
cracks, porosity, cold shuts, fatigue cracks, grinding cracks etc. The ZYGLO test
works effectively in a variety of porous and non-porous materials: aluminum,
magnesium, brass, copper, titanium, bronze, stainless steel, sintered carbide, non-
magnetic alloys, ceramics, plastic and glass. Various steps of this test are given
below:-
Step 1 – pre-clean parts.
Step 2 – apply penetrant
Step 3 – remove penetrant
Step 4 – dry parts
Step 5 – apply developer
Step 6 – inspection
(d) RED DYE PENETRATION TEST (RDP)
Dye penetrant inspection (dpi), also called liquid penetrant
inspection (lpi), is a widely applied and low-cost inspection method used to locate
surface-breaking defects in all non-porous materials (metals, plastics, or ceramics).
penetrant may be applied to all non-ferrous materials, but for inspection of ferrous
components magnetic particle inspection is preferred for its subsurface detection
capability. lpi is used to detect casting and forging defects, cracks, and leaks in new
products, and fatigue cracks on in-service components.
YEARY MECHANICAL TESTING
35. 35
TESTING OF MECHANICAL SYSTEM(FIG 14)
In this section, major schedules suchas M-24, M48 and M-72 are carried out. Here,
complete overhauling of the locomotives is done and all the parts are sent to the
respective section and new parts are installed after which load test is done to check
proper working of the parts. The work done in these sections are as follows:
1). Repeating of all items of trip, quarterly and monthly schedule.
2). Testing of all valves of vacuum/compressed air system. Repair if necessary.
3). Replacement of coalesce element of air dryer.
36. 36
(4). Reconditioning, calibration and checking of timing of FIP is done. Injector is
overhauled.
(5). Cleaning of Bull gear and overhauling of gear-case is done.
(6). RDP testing of radiator fan, greasing of bearing, checking of shaft and keyway.
Examination of coupling and backlash checking of gear unit is done.
(7). Checking of push rod and rocker arm assembly. Replacement is done if bent or
broken. Checking of clearance of inlet and exhaust valve.
(8). Examination of pistonfor cracks, renew bearing shell of connecting rod fitment.
Checking of connecting rod elongation.
(9). Checking of crankshaft thrust and deflection. Shims are added if deflection is
more then the tolerance limit.
(10). Main bearing is discarded if it has embedded dust, gives evidence of fatigue
failure or is weared.
(11). Checking of cracks in water header and elbow. Install new gaskets in the air
intake manifold. Overhauling of exhaust manifold is done.
(12). Checking of cracks in crankcase, lube oil header, jumper and tube leakage in
lube oil cooler. Replace or dummy of tubes is done.
(13). Lube oil system- Overhauling ofpressureregulating valves, bypass valve, lube
oil filters and strainers is done.
(14). Fuel oil system- Overhauling ofpressureregulating valve, pressurerelief valve,
primary and secondary filters.
(15). Checking of rack setting, governor to rack linkage, fuel oil high-pressure line
is done.
(16). Cooling water system- draining ofthe cooling water from system and cleaning
with new water carrying 4 kg tri-phosphate is done. All water system gaskets are
replaced. Water drain cockis sealed. Coppervent pipes are changed and water hoses
are renewed.
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(17). Complete overhauling of water pump is done. Checking of impeller shaft for
wear and lubrication of ball bearing. Water and oil seal renewal.
(18). Complete overhauling of expressor/compressor, pistons rings and oil seal
renewed. Expressor orifice test is carried out.
(19). Complete overhauling of Turbo supercharger is done. Dynamic balancing and
Zyglo test of the turbine/impeller is done. Also, hydraulic test of complete Turbo
supercharger is done.
(20). Overhauling of after-cooler is done. Telltale hole is checked for water leak.
(21). Inspection of the crankcase cover gasket and diaphragm is done. It is renewed
if necessary.
(22). Rear T/Motor blower bearing are checked and changed. Greasing of bearing is
done.
(23). Cyclonic filter rubber bellows and rubber hoses are changed. Air intake filter
and vacuum oil bath filter are cleaned and oiled.
(24). Radiators are reconditioned, fins are straightened hydraulic test to detect
leakage and cleaning by approved chemical.
(25). Bogie- Checking of frame links, spring, equalizing beam locating roller pins
for free movement, buffer height, equalizer beam for cracks, rail guard distance is
done. Refilling of center plate and loading pads is done. Journal bearings are
reconditioned.
(26). Axle box- cleaning of axle box housing is done.
(27). Wheels- inspection for fracture or flat spot. Wheel are turned and gauged.
(28). Checking of wear on horn cheek liners and T/M snubber wear plates.
(29). Checking of brake parts for wear, lubrication of slack adjusters is done.
Inspection for fatigue, crack and distortion of center buffers couplers, side buffers
are done.
38. 38
PROJECT STUDY
TO STUDY ABOUT THE
DIESEL BOGIE
BOGIE SECTION
BOGIE (FIG 15)
This is the part (called the bogie) carrying the wheels and traction
motors of the locomotive. A pair of train wheels is rigidly fixed to an axle to form a
wheel set. Normally, if two wheel sets are mounted in a bogie it is known as BO-BO
type, but if three wheel sets are mounted on truck, it is called as CO-CO type. Most
bogies have rigid frames as shown below.
39. 39
The bogie frame is turned into the curve by the leading wheel set as it
is guided by the rails. However, there is a degree of slip and a lot of force required
to allow the change of direction. The bogie carries about half the weight of the
vehicle it supports. It also guides the vehicle, sometimes at high speed, into a curve
against its natural tendency to travel in a straight line. They provide the propulsion,
the suspensions and the braking. As you can imagine, they are tremendous
structures.
The trucks also provide the suspension for the locomotive. The weight
of the locomotive rests on a big, round bearing which allows the trucks to pivot so
the train can make a turn. Below the pivot is a huge leaf spring that rests on a
platform. The platform is suspended by four, giant metal links, which connect to the
boogie assembly. These links allow the locomotive to wing for side to side.
The weight of the locomotive rests on the Helical springs and Leaf
spring, which compress when it passes over a bump. The links allow the trucks to
move from side to side with fluctuations in the truck. The truck is not perfectly
straight, and at high speeds, the small variations in the track would make for a rough
ride if the trucks could not swing laterally. The system also keeps the amount of
weight on each rail relatively equal, reducing wear on the tracks and wheels.
There are three pivots on which the load is distributed as 60%, 20%,
20% respectively on centre pivot, on two side bearers which are elliptical in shape.
For distributing the load equally on the axles the equalizer beams are used.
(a)While running the defects which generally occur are:-
1. Crack in equalizer due to stress concentration.
2. Breaking of centre pivot due to inertia force.
3. There might be failure of spring.
4. Cylinder head section
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The working of cylinder head is to do maintenance work on the cylinder head.
The maintenance and testing ofcylinder ofcylinder head is donebythis section.
The complete overhauling procedures includes the following steps:-
1. Disassembling of valves and their springs and checking the tapered
face of the valve kept for the indentations.
2. Washing of head, it is done for about 4 hours.
3. The separated parts are sending for zyglo-test.
4. All the clearances are checked and the two main tests (Hydraulic
testing to checkthe cracks in the water jackets and Blow By to check
the proper seat matching of the cylinder head and liner) are done.
5. Assembling of all parts is done.
TYPES OF BOGIE
(a)CO-CO LOCOMOTIVES
Co-Co is a codefor a locomotive wheel arrangement with two six-
wheeled bogieswith all axles powered, with a separate motor per axle. Co-Co is the
codefor a similar wheel arrangement but with an articulated connection between
the bogies. The equivalent UIC classification for this arrangement is Co′Co′.
Co-Cos are most suited to freight work as the extra wheels give them
good traction. They are also popular because the greater number of axles results in
a lower axle load to the track
Notable examples include the British Rail Class 47, the Soviet M62
locomotive and the EMD Series 66, mainstay of many current European heavy rail
haulage fleets, over 500 having been built to date. The very
strong IORE locomotive has this also, but to allow higher locomotive weight, 30
tonnes per axle.
41. 41
CO CO ARRANGEMENT
(b)Bo-Bo LOCOMOTIVES
Bo-Bo is the UIC indication of a wheel arrangement for railway
vehicles with four axles in two individual bogies, all driven by their own traction
motors. It is a common wheel arrangement for modern electric and diesel-electric
locomotives, as well as power cars in electric multiple units.
Most early electric locomotives shared commonalities with the steam
engines of their time. These features included side rods and frame mounted driving
axles with leading and trailing axles. The long rigid wheelbase and the leading and
trailing axles reduced cornering stability and increased weight.
The Bo-Bo configuration allowed for higher cornering speeds due to
the smaller rigid wheelbase. Furthermore it allowed better adhesion because all the
wheels were now powered. Due to the absence of frame mounted wheels no
leading or trailing axles were necessary to aid cornering, reducing weight and
maintenance requirements.
Due to the advent of modern motors and electronics more power can
be brought to the rail with only a few axles. Modern electric locomotives can
deliver up to 6400 kW on only four axles. For very heavy loads, especially in
transportation of bulk goods, a single unit with this wheel arrangement tends to
42. 42
have too little adhesive weight to accelerate the train sufficiently fast
without wheelslip.
Bo Bo ARRANGEMENT(FIG 16)
BOGIE PARTS & DESCRIPTION
43. 43
The bogie, or truck as it is called in the US, comes in many shapes and
sizes but it is in its most developed form as the motor bogie of an electric or diesel
locomotive or an EMU. Here it has to carry the motors, brakes and suspension
systems all within a tight envelope. It is subjected to severe stresses and shocks and
may have to run at over 300 km/h in a high speed application. The following
paragraphs describe the parts shown on the photographbelow, which is of a modern
UK design. Click on the name in the picture to read the description.
BOGIEFRAME(FIG 17)
(a)BOGIE FRAME
Can be of steel plate or cast steel. In this case, it is a modern design of
welded steel box format where the structure is formed into hollow sections of the
required shape.
44. 44
(b)BOGIE TRANSOM
Transverse structural member of bogie frame (usually two off) which
also supports the carbody guidance parts and the traction motors.
(c)BRAKE CYLINDER
An air brake cylinder is provided for each wheel. A cylinder can
operate tread or disc brakes. Some designs incorporate parking brakes as
well. Some bogies have two brake cylinders per wheel for heavy duty braking
requirements. Each wheel is provided with a brake disc on each side and a brake
pad actuated by the brake cylinder. A pair of pads is hung from the bogie frame and
activated by links attached to the piston in the brake cylinder. When air is admitted
into the brake cylinder, the internal piston moves these links and causes the brake
pads to press against the discs. Abrake hanger supportbracket carries the brake
hangers, from which the pads are hung.
(d)PRIMARY SUSPENSION COIL
A steel coil spring, two of which are fitted to each axlebox in this
design. They carry the weight of the bogie frame and anything attached to it.
(e) MOTOR SUSPENSION TUBE
Many motors are suspended between the transverse member of the
bogie frame called the transom and the axle. This motor is called "nose suspended"
because it is hung between the suspension tube and a single mounting on the bogie
transom called the nose.
(f)GEARBOX
This contains the pinion and gearwheel which connects the drive from
the armature to the axle.
(g)LIFTING LUG
Allows the bogie to be lifted by a crane without the need to tie chains
or ropes around the frame.
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(h)MOTOR
Normally, each axle has its own motor. It drives the axle through the
gearbox. Some designs, particularly on tramcars, use a motor to drive two axles
(i)NEUTRAL SECTION SWITCH DETECTOR
In the UK, the overhead line is divided into sections with short neutral
sections separating them. It is necessary to switch off the current on the train while
the neutral section is crossed. A magnetic device mounted on the track marks the
start and finish of the neutral section. The device is detected by a box mounted on
the leading bogie of the train to inform the equipment when to switch off and on.
(j)SECONDARY SUSPENSION AIR BAG
Rubber air suspension bags are provided as the secondary suspension
system for most modern trains. The air is supplied from the train's compressed air
system.
Wheel Slide Protection System Lead to Axlebox Where a Wheel Slide
Protection (WSP) system is fitted, axleboxes are fitted with speed sensors. These
are connected by means of a cable attached to the WSP box cover on the axle end.
(k)SHOCK ABSORBER
To reduce the effects ofvibration occurring as a result ofthe wheel/rail
interface.
(l)AXLEBOX COVER
Simple protection for the return current brush, if fitted, and the axle
bearing lubrication.
CONCLUSION
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I have completed my training from the DIESEL
LOCOMOTIVE WORKSHOP , GONDA . I have observed many shop
in the workshop I mainly performed my training in the BOGIE
SECTION.
In the locomotive workshop ,all the SSE and JE and
SUPERVISIORS of all te shops helped very much. Without his or her
supervision I was not able to perform the training in all the workshops. I
am very grateful to him .
We have learned too much in the workshop, DIFFERENT
TYPE OF WORKSHOP TECHNOLOGY, TESTING OF THE PARTS
OF THE LOCOMOTIVE AND THE PROPER FUNCTIONING of the
different locomotive parts as a TURBOSUPERCHARGER,
EXPRESSOR, POWER PACK OF THE LOCOMOTVE , RADIATOR
SECTION ,OIL SUMP, DYNAMO AND BOGIE AND
FABRICATION OF THE BODY OF LOCOMOTIVE .
REFRENCES
47. 47
Workshop technology by Hazara & Chaudhary
Production technology by P.C. SHARMA
Study material provided by TECHNICAL TRAINING CENTRE
Workshop technology by S. K. GARG
WWW.RAILWAY TECHNICAL.CO.IN
WWW.HOWSTUFFWORKS.IN
WWW.IRFCA.CO.IN