HRTC WORKSHOP TRAINING BAIJNATH

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HIMACHAL ROAD TRANSPORT CORPORATION
INDUSTRIAL TRAINING REPORT
Submitted in partial fulfillment of the requirements for the degree of
Bachelor of Engineering
(Mechanical Engineering)
Submitted To Submitted By
Mechanical Engineering Department Akshay Kumar
CHANDIGARH UNIVERSITY 14BME8004
CHANDIGARH UNIVERSITY
NH-95, Vill. Gharuan, Distt. Mohali
Punjab, 140413

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ACKNOWLEDGMENT
No Endeavour can be successful without the active cooperation of the people concerned
with it, which was fourth coming in full during this study. It is extremely difficult to find
words which can do justice to this sort of cooperation.
I am deeply indebted to Mr. Baini Parshad Bharmoriya (Regional Manager)H.R.T.C.
WORKSHOP BAIJNATH who allowed me feel lucky to complete my training under the
table and competent guidance of Workshop Manager.
I am extremely grateful faculty members for their whole hearted co-operation.
I extend my deepest gratitude to all those persons who supported me all through my
training. My interaction with all these people has left a long lasting impression in my mind
that will influence my project and my behavior for all times to come.
Akshay
14BME1038
ME (5TH SEM)

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INDEX
S.No. CONTENT PAGE No.
1 Introduction 4
2 Basic information about H.R.T.C. 5
3 About H.R.T.C. workshop Palampur 6
5 Safety guidelines 7
6 Bus type 8
9 Engine 11
10 Main parts of engine 12
11 Gearbox 26
12 Differential 33
13 Braking & steering system 37
14 Conclusion 43
15 Bibliography 44

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INTRODUCTION
This training is done at H.R.T.C. Workshop which comes under BAIJNATH (HP)
Division. This Workshop is undertaking the work of repair of H.R.T.C. Ordinary, Semi
Deluxe and Deluxe buses. These divisional Workshops undertake the major repair work of
buses of Units falling under the respective division.
This industrial training is described under syllabus and required for experience and practical
knowledge. We had studied all kinds of the theoretical things about Clutches, Brakes,
Engine, Gear Box, Fuel Injection Pump and all the things related to our “Mechanical Branch”.
In this workshop the Fabrication of Buses is done on Chassis which are brought from there
respective Motor Company. Here different departments were also made fort here pair and
maintenance purposes. Here during this training I have seen all things and done practically
which has helped to en rich my knowledge greatly. This project report is all what I have seen
in the H.R.T.C. workshop and done practically with my hands. I am really thankful to all
staff members of the H.R.T.C. and the workers with whose helpful nature and guidance
I completed my Industrial training and Project Report.

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BASIC INFORMATION ABOUT H.R.T.C.
a) ORGANISATIONAL STRUCTURE
Himachal road Transport Corporation is held by the Board of Directors with Transport
Minister as the Chairman. Managing Director is the Chief Executive of the corporation.
Himachal Road Transport Corporation has three tier structures. The corporate office at
Shimla controls 4 Divisional offices located at Shimla, Mandi, Hamirpur and
Dharamshala. These four divisions control 23 Regional offices under them.
Dharamshala Dharamshala, Pathankot, Chamba, Palampur,
Baijnath, Jassur.
b) STATASTICS OF H.R.T.C.
PARTICULARS STATUS ON 2.10.1974 2016
Number of buses 733 2645
Number of routes 379 22645
Annual coverage 3.03 crore kms 21 crore kms
Number of divisions Nil 4

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ABOUT H.R.T.C. WORKSHOP BAIJNATH
Workshop is a place where repair a change of the parts of the vehicles is done or in other
words it is place where theory or changes practically to the original structure. The
corporate office at Shimla controls 4 divisional offices located at Shimla, Mandi, Hamirpur
and Dharamshala. These 4 divisions control 23 regional offices under them. Dharamshala
division has 5 regions in it. These regions are Pathankot, Chamba, Palampur, Baijnath,
Jassur.
Baijnath consist of 2 workshops, one is divisional workshop and other is regional
workshop. In H.R.T.C. workshop Baijnath there are about 65 staff members. The others are
related to the clerical staff or other officers such as R.M., D.M. and workshop manager.
There are about 11o buses run under Baijnath division. Assemblies like engine, gearbox,
steering box etc. are overhauled. There is big store in the workshop in which every part in
it place use catalogue to give a part to the workshop manager and head mechanic check the
working of every worker they told to the worker.

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SAFETY GUIDELINES
To avoid accidents & to keep them from happening following safety guidance should
be allowed.
• Provide your attention at most to the job & work quietly.
• Keep the tools with in your convenient reach. Arrange neatly without scattering
them around.
• Always keep jack handles pointing up to avoid tripping up to. When creepers are
not in use stand than against the wall to avoid stumbling over then.
• Be serious about your never including in horseplay or other foolish activities to
avoid injury to other.
• Never put sharp objects like screwdriver in your pocket otherwise you will cut
yourself or get stabled or ruin the up hot slay of a vehicle.
• Always wear suitable clothes for the job serious injuries are liable be caused by
cleaning sleeve or lies getting caught the machining sandals or open to be worn full
leather with non skid rubber heel & shoe or steel to safety shoe should be worn.
• To provide good grip on tool or part always wipe excess oil and grease up fly our
hand tool.
• To avoid one sleeping and falling to the ground due to split of oil grease or any
liquid clean up immediately.
• Compressed air should, never be used to below dust from your clothes. Compressed
a hose should never be pointed to any person because fling particles may harm him.
• Wheel welding and grinding always water out for flying speak which can set your
clothes on fire.
• To hold the bus safety & work under it safety always us bus stand and jack it up
properly.

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BUSTYPES
HRTC is operating four types of buses:-
1. Ultra luxury AC Buses – HIMSUTA
2. Luxury AC Buses - HIMGAURAV
3. Semi Deluxe Buses
4. Ordinary Buses
Ultra Luxury Air Conditioned Buses (HIMSUTA)
HRTC is operating Ultra Luxury AC Buses (Volvo &its equivalent)from
Delhi to Shimla, Manali and Dharamsalavice versa. Theses buses are equipped
with latest andcomfortable facilities to the passengers.

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Luxury AC Buses (HIMGAURAV)
HRTC is operating Luxury AC Buses (2X2) to and fro Delhi from Shimla, Manali,
Dharamsala and Palampur. These buses are equipped with Luxury Push Back Seats.
Semi Deluxe Buses
HRTC is operating nonAC Deluxe Buses (2X2) to andfro Delhi from Shimla,
Manali, Dharamsala and Palampur. Theses buses are equippedwith Luxury Push
Back Seats.

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Ordinary Buses
Ordinary Buses (2X3) are equipped with latest comfortable hi-tech seats. These buses are
pliedon long and intra-state routes on ordinary fare to provide the passengers economic
comfortable journey.

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ENGINE
An engine is mechanical device which converts one form of energy into other or It is a power
producing device or machine which converts chemical energy of fuel into heat energy and then
into mechanical work.
A typical engine of Tata 1510 TC
The power system of an automobile is the engine.it is the heart of the automobile. In the
power system, an assembly of the large number of parts is used to do work and make transfer
of energy. This energy is stored in the flywheel connected to the crankshaft. The flywheel
connected to the crankshaft. The flywheel transmits this energy to wheels through the
transmission system.in this way the power i.e. the engine sets the vehicle in motion.

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Main parts of engine:-
1. Cylinder block
2. Cylinder head
3. Pistons
4. Turbo charger
5. Crankshaft
6. Camshaft
7. Rocker arm
8. Flywheel
9. Fuel injection pump
10. Injector nozzle
11. Thermostat
12. Radiator
13. Oil sump
14. Fuel filter
15. Dampers
16. Manifolds (inlet and outlet)
17. Valves (inlet valve and outlet valve)
18. Connecting rod
19. Timing housing plate

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DETAILS OF PARTS AND THEIR FUNCTIONS:-
The function of engine parts are following:-
1. Cylinder block:-
Cylinder block of a diesel engine
The main body of the engine to which the piston cylinders are attached and which contains the
crankshaft and crankshaft bearing is called bearing is called crankcase and cylinder block. This
member also hold other parts in alignment and resist the explosion and inertia force.it also
protect the parts from the dirt etc. and serves as part of lubrication system.

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2. Cylinder head:-
A typical cylinder head of diesel engine
Attached or made integral part of crank case. The cylinder is either integral part or linear inserted
in which the piston reciprocates to develop power.it withstand a very high pressure and
temperature due to direct combustion. For the water cooled engine water jackets i.e. Hollow
spaces are provided for the water circulation .it is made of cast iron.

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3. Pistons:-
Piston and connecting rod assembly
Main functions of pistons are:
• To transmit the force of explosion to the crankshaft.
• To serve as a guide and bearing for the small end of the connecting rod.
• To form a seal so that the high pressure gases in the combustion chamber do not escape
in the crank case.

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4. Turbo charger:-
Basically it is an air compressor which is used to supply air to the inlet manifold at higher
content. By this complete combustion of the fuel in the combustion chamber take place.
Turbo charger is now used in vehicle.it is attached to the exhaust gases are carried out by exhaust
manifold. We can use this exhaust gases and also minimize the exhaust gases and used it for
power supply. There are two turbines in turbo charger which are connecting each other with the
shaft. The exhaust gases went into the turbine, rotate it and produced power.

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5. Crankshaft:-
The crank shaft is said to be backbone of the engine.it receives oscillation motion from the
connection rod and gives to the main shaft a rotatory motion. It also drives the camshaft which in
turn operates the values of the engine.it is made up of forged steel.
6. Cam shaft:-

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A camshaft is a shaft with the cam for each intake and exhaust valve. Each cam has high spot
called cam bob which control the valve opening. It rotates half of the camshaft.
One four stroke cycle is complete in two revolution of the crank shaft each cam must
open and close the inlet and exhaust valve once every two revolution of the crankshaft.
7. Flywheel:-
A flywheel is an electromechanical device that couples a motor generator with a rotating mass to
store for short duration.
Fig:-Flywheel
Conventional flywheel are “charged” and “discharged” via an integral motor/generator. The
motor /generator draws provided by the grid to spin the rotor of the flywheel. During the power
outage, voltage sag, or other disturbance t e motor/generator provides power. The kinetic energy
stored is transformed to dc electric energy by generator, and the energy is delivered at constant

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frequency and voltage through an inverter and controls system. Traditional flywheel rotors are
usually constructed of steel and are limited to a spin rate of few thousand revolutions per minute.
8. Connecting rod :-
In a reciprocating piston engine, the connecting rod or con rods connects the piston to the crank
or crankshaft. Together with the crank, they form a simple mechanism that converts linear
motion into rotating motion.
Today the connecting rods are best known through their use in internal combustion piston
engines, such as bus engines. These are of distinctly different design from the earlier form of
connecting rods, used in steam engine and steam locomotives.

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9. Fuel injection pump :-
Fig:- FUEL INJECTION PUMP
F.I. Pump uses solenoid valves called injectors to meter fuel delivery. Most of the vehicles
today use 1 injector per cylinder. When the solenoid is energize, fuel sprays out into the valve
port. Fuel is delivered to injector by the high pressure electric pump at around 40 psi. Fuel
delivery is controlled by the injectors which are cycled by the computers. The computers
produced the signal to open the injectors for the certain length of the time depending on the
engine conditions relayed by the sensors. The longer injector open, the more is fuel is injected.

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10. Thermostat :-
The basic purpose of a thermostat is to trap the coolant & water around the engine block in order
to help the engine reach operating temperature more quickly. As soon as the temperature gets hot
enough, the thermostat must open, allowing the coolant to flow throughout the entire cooling
system (hoses, radiator, etc.). When taking your vehicle to an auto repair shop, beware of any
mechanic who immediately suggests a new radiator; the problem may be as simple as a stuck
thermostat. Automotive engine operating temperature must be reached as quickly as possible and
it must be kept at a specific level. The proper operating temperature of a vehicle affects fuel
economy, performance, emissions, and longevity. If an engines operating temperature is too low,
fuel delivery is affected, carbon builds up in the engine, wear is increased and performance can
suffer. In addition, heater outlet temperatures can be too low. Because of this, a thermostat is
used to maintain the engine at a proper temperature. Thermostats used in most vehicles are of the
pellet type, poppet valve design. A pellet, containing a material that expands with temperature,
moves a rod that opens a poppet valve, to allow coolant flow at a required temperature.

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Thermostats also contain a small hole that allows air and steam to escape from the engine into
the radiator when the thermostat is closed. Most cooling system designs provide a means for
coolant to flow to the water pump when the thermostat is closed. This is called bypass flow.
Coolant is circulated by the water pump through the engine until it reaches the closed thermostat.
A small amount of coolant flows back to the water pump via a passage or a hose, to be
recirculate through the engine. This helps to provide faster warm up for the engine and to prevent
water pump damage. Once the thermostat opens, normal coolant flow through the radiator is
resumed.
11. Injector pipe :-
An injector, ejector, steam ejector, steam injector, educator-jet pump or thermo compressor is
a like device that uses the Ventura of a converging-diverging nozzle to convert
the pressure energy of a motive fluid to velocity energy which creates a low pressure zone that
draws in and entrains a suction fluid. After passing through the throat of the injector, the mixed
fluid expands and the velocity is reduced which results in recompressing the mixed fluids by
converting velocity energy back into pressure energy. The motive fluid may be a liquid, steam or
any other gas. The entrained suction fluid may be a gas, a liquid, slurry, or a dust-laden gas
stream. The adjacent diagram depicts a typical modern ejector. It consists of a motive fluid inlet

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nozzle and a converging-diverging outlet nozzle. Water, air, steam, or any other fluid at high
pressure provides the motive force at the inlet. An injector is a more complex device containing
at least three cones. That used for delivering water to a steam locomotive boiler takes advantage
of the release of the energy contained within the latentheat of evaporation to increase the
pressure to above that within the boiler. The Ventura effect, a particular case
of Bernoulli'sprinciple, applies to the operation of this device.
12. Radiator :-
The Cat Cooler™ aluminum radiator is the first and only direct fit, aluminum radiator
specifically designed by Jaguar specialists for Jaguar V12 cars. All fittings (inlets, outlet, and
transmission cooler, mounting pegs) are in the original Jaguar factory locations. Unlike other
aluminum radiators sold for the Jaguar V12 no modifications, expensive adaptors or other work
around are necessary. This is a true drop in replacement for the factory radiator. The difference is
that the Cat Cooler™ radiator, with a 2 1/4 inch thick core and two rows of one inch diameter
tubes with 18 fins per inch, has a cooling capacity approximately 40% greater than the stock
Jaguar radiator. The Cat Cooler™ is made in the USA from quality materials and is 100% tig
welded with absolutely no epoxy used in any way. We've even added a draincock and alternative
water temperature sensor location as improvements to the original Jaguar design. Installation is

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exactly the same as for the OEM radiator and the Cat Cooler™ will fit and work with either the
original cooling fans or the Cat Cooler™ twin electric cooling fan system.
Tools and equipment :-
a) Spanners
b) Ring spanners
c) Hammer
d) Valve spring remover
e) Socket set
f) Pliers
Defects:-
• Breakage of the crankshaft & gear teeth
• Wear out in piston.
• Breakage of the piston rings.
• Corrosion of the cylinders.

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GEARBOX
A gearbox is used to alternate the rotational speed and torque that the engine delivers to the drive
wheels of a vehicle. It uses different gear ratios to achieve it. The synchronizer’s job is to bring
the next gear ratio (up shift or down shift) up to speed so that out put shaft and the gears are at
the same speed to allow for a smooth gear change. Earlier, when "synchronizers" were not used
one had to double-clutch for allowing gear shift on the go. At every gear shift one had to press
and release the clutch twice, hence the name "double-clutching." It was an art to avoid gear
clashing. Modern automobile Blocker Ring Synchronizers in order to avoid the need for double-
clutching.
Function of Gear Box:
An automobile is able to provide varying speed and torque through its gear box. Various
functions of a gear box are listed below:
(a) To provide high torque at the time of starting, vehicle acceleration, climbing up a hill.

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(b) To provide more than forward speeds by providing more than one gear ratios. In modern cars,
five forward gears and reverse gear is provided. For given engine speed, higher speed can be
obtained by running in higher (4th and 5th) gears.
(c) Gear box provides a reverse gear for driving the vehicle in reverse direction.
Component of Synchromesh gear box:
1. Gear Box: This is the body in which all the component of gear box are assembled. It
consist of two plug, one is for OIL LEVEL PLUG and second is for OIL DRAIN PLUG.
2. Main Shaft: Shaft on which all gear are mounted. Gear shifting sleeve are also mounted
on it. Small groove are present on main shaft.
3. Lay Shaft: Lay shaft consist of gear which are always in mesh with the gears which is on
main shaft.
4. Gears: Different gear are present on shaft which having different number of teeth.
Constant gear take power from clutch and transmit to lay shaft.
5. Gear Shifting sleeve: These are mounted on main shaft. It one for two gears.
It has teeth on inner side.
6. Gear Shifting Fork: These are attached on gear box and fork are assemble on sleeve.
7. Covering finger: It is used to change gear.
8. Synchronizer: It has teeth on outer side which come in contact with inner teeth of sleeve.
And also it has friction material which initially come in contact with gear so that it can
gain speed before assemble with it.
It also eliminate the problem of double declutching.

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For dismantling & assembling of gearbox tools are used :-
• Hammer
• Chisel
• Tommy bar
• Open end spanner
• Extension rod
• Iron stick
• Socket set
• Ring spanner
• Nose pilers
• Speed handle
No. of gears :-
 5 Forward
 1Reverse
Gear ratio :-
 1st – 7.51
 2nd – 3.99
 3rd – 2.30
 4th -1.39
 5th -1.00
 Rev.-6.43

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Disassembly of gear box:-
 Gear box hosing.
 Coupling plunger.
 Shifting fork.
 Shaft.
 Shifting sleeve
 Primary shaft
 Main shaft
 Counter shaft
 Idle or rev. shaft
Counter shaft has one fixed gear, if the counter shaft has smaller gear than main shaft in its
opposite meshes its bigger gear.

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Assembly of gear box :-
After dismantling the gear box first the gear box is washed with the help of diesel & other
components are also wash with it. Then with the help of pressured water all the components &
gear box is washed for complete cleaning. Gasket is fixed in the gear box cover & grease is also
used to prevent the leakage of oil.

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Defects:-
• Gear teeth broken.
• Play b/w gear component.
• Bearing is not smooth running.
• The teeth of fork are broken.
• Components of the gear shift mechanism may be worn or damaged.
• Counter shaft gear may be worn out.
• Splines on the shaft may be worn out.
• Miss alignment of countershaft & main shaft gears.

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PROPELLER SHAFT :
Propeller shaft is the combination of three component
1. Shaft
2. Universal joint
3. Slip joint
A drive shaft and universal joints (U-joints) connect the transmission to the
rear drive axle on most rear-wheel-drive vehicles. Many four-wheel-drive vehicles also use drive
shafts and universal joints, with one drive shaft between the transfer case and rear drive axle and
a second drive shaft between the transfer case and the front drive axle. The drive shaft is
sometimes called a propeller shaft.
Purpose: The drive shaft and U-joints provide a means of transferring engine torque to drive
axles. The universal joints allow the drive shaft to move up and down, to allow for suspension
travel.

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Universal Joint: It is the combination of two yoke and one spider. Which provide up and
down, and left and right moment of shaft.
DIFFERENTIAL:
Function of differential:
•Transfers power from driveshaft to the wheels.
•Provides final gear reduction.
•Splits amount of torque going to each wheel.
•Allow the wheels to rotate at different speeds in turns

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Parts of Differential:
Pinion Drive Gear: transfers power from the driveshaft to the ring gear.
Ring Gear/Crown wheel: transfers power to the Differential case assembly.

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Differential case assembly: holds the planet gear and other components that drive the rear
axle.
Reardrive axles:steel shafts that transfer torque from the differential assembly to the drive
wheels.
Rearaxle bearings: Roller bearings that fit between the axles and the inside of the axle
housing.
Axle housing:Metal body that encloses and supports parts of the rear axle assembly.
Sun gear:Help both wheels to turn independently when turning.
Planetgear: Transmit power from crown wheel to sun gear.

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Power flow:
•Drive shaft spins the Pinion gear.
•Pinion gear turns the larger ring gear to produce gear reduction.
•Ring gear attached to differential case, hence it rotates with the ring gear.
•Differential case spins the sun gears which are attached to the axles.
•Axles transfer the power to the wheels.
Half Axle:
Half axle transmit power from sun gear of differential to wheel. Name is half axle because it
transmit half of power to wheel.
Working of DIFFERENTIAL:-
When the vehicle is travelling in the straight head position, the power flow from the drive pinion
. The drive pinion gives the power to the crown wheel whereas crown wheel, cage the pin & the
planet pinion rotate as one unit. The planet pinion does not revolve on the pin as their axes but
transmit the power to sun gears. The sun gears & the half shaft are splined together and revolve
due to the rotary motion of the planet gears as whole when the vehicle is taking turn; the planet
gear rotates on its shaft to permit the outer rear wheel to turn more quickly than the inner rear
wheel.

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BRAKING & STEERING SYSTEM:-
Automotive braking system has two types of brakes:
• The service brakes, operated by a foot pedal, which slow or stop the vehicle.
• The parking brakes, operated by foot pedal or hand lever, which hold the vehicle
stationary when applied.
Air brake system:-
Compressed air brake systems are typically used on heavy trucks and buses. The system consists
of service brakes, parking brakes, a control pedal, an engine-driven air compressor and a
compressed air storage tank. Compressed air brake system uses both disc and drum brake
arrangement. Most types of truck air brakes are drum units, though there is an increasing trend
towards the use of disc brakes in this application. The air compressor draws filtered air from the
atmosphere and forces it into high-pressure reservoirs at around 120 PSI. Most heavy vehicles
have a gauge within the driver's view, indicating the availability of air pressure for safe vehicle
operation, often including warning tones or lights. Setting of the parking/emergency brake
releases the pressurized air pressure in the lines between the compressed air storage tank and the
brakes, thus actuating the (spring brake) parking braking hardware. An air pressure failure at any
point would apply full spring brake pressure immediately.
Brakes are applied by pushing down the brake pedal. (It is also called the foot valve.) Pushing
the pedal down harder applies more air pressure. Letting up on the brake pedal reduces the air
pressure and releases the brakes. Releasing the brakes lets some compressed air go out of the
system, so the air pressure in the tanks is reduced. It must be made up by the air compressor.
Pressing and releasing the pedal unnecessarily can let air out faster than the compressor can
replace it. If the pressure gets too low, the brakes won't work. These large vehicles also have an
emergency brake system, in which the compressed air holds back a mechanical force (usually a
spring) which will otherwise engage the brakes. Hence, if air pressure is lost for any reason, the
brakes will engage and bring the vehicle to a stop.

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Component of air brake system:-
Air Compressor :-
The air compressor pumps air into the air storage tanks (reservoirs). The air compressor is
connected to the engine through gears or a v-belt. The compressor may be air cooled or may be
cooled by the engine cooling system. It may have its own oil supply or be lubricated by engine
oil. If the compressor has its own oil supply, check the oil level before driving.
1. Air Compressor Governor
The governor controls when the air compressor will pump air into the air storage tanks. When air
tank pressure rises to the "cut-out" level (around 125 pounds per-square-inch or "psi"), the
governor stops the compressor from pumping air. When the tank pressure falls to the "cut-in"
pressure (around 100 psi), the governor allows the compressor to start pumping again.
2. Air Storage Tanks
Air storage tanks are used to hold compressed air. The number and size of air tanks varies among
vehicles. The tanks will hold enough air to allow the brakes to be used several times, even if the
compressor stops working.
Air Tank Drains

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Compressed air usually has some water and some compressor oil in it, which is bad for the air
brake system. For example, the water can freeze in cold weather and cause brake failure. The
water and oil tend to collect in the bottom of the air tank. Be sure that you drain the air tanks
completely. Each air tank is equipped with a drain valve in the bottom.
3. The Brake Pedal
You put on the brakes by pushing down the brake pedal. (It is also called the foot valve or treadle
valve.) Pushing the pedal down harder applies more air pressure. Letting up on the brake pedal
reduces the air pressure and releases the brakes. Releasing the brakes lets some compressed air
go out of the system, so the air pressure in the tanks is reduced. It must be made up by the air
compressor. Pressing and releasing the pedal unnecessarily can let air out faster than the
compressor can replace it. If the pressure gets too low, the brakes won't work.
4. Brake Drums, Shoes, and Linings:
Brake drums are located on each end of the vehicle's axles. The wheels are bolted to the drums.
The braking mechanism is inside the drum. To stop, the brake shoes and linings are pushed
against the inside of the drum. This causes friction, which slows the vehicle (and creates heat).
The heat a drum can take without damage depends on how hard and how long the brakes are
used. Too much heat can make the brakes stop working

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.
SHOE BRAKE LINING
5. S-cam Brake
When you push the brake pedal, air is let into each brake chamber. Air pressure pushes the rod
out, moving the slack adjuster, thus twisting the brake camshaft. This turns the s-cam (so called
because it is shaped like the letter "S"). The s-cam forces the brake shoes away from one another
and presses them against the inside of the brake drum. When you release the brake pedal, the s-
cam rotates back and a spring pulls the brake shoes away from the drum, letting the wheels roll
freely again

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The above shown s-cam brakes are most commonly used in H.R.T.C. buses.
5. Wedge brakes
In this type of brake, the brake chamber push rod pushes a wedge directly between the
ends of two brake shoes. This shoves them apart and against the inside of the brake drum. Wedge
brakes may have a single brake chamber, or two brake chambers, pushing wedges in at both ends
of the brake shoes. Wedge type brakes may be self-adjusting or may require manual adjustment.
6. Supply Pressure Gauges
All vehicles with air brakes have a pressure gauge connected to the air tank. If the vehicle has a
dual air brake system, there will be a gauge for each half of the system. (Or a single gauge with
two needles. These gauges tell you how much pressure is in the air tanks.

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STEERING MECHANISM
The steering mechanism allows the driver to control the direction of vehicle travel. This is made
possible by linkage that connects the steering wheel to the steerable wheels and tires. The
steering system may be either manual or power. The only energy source for the steering system
is the force the driver applies to the steering wheel, the vehicle has manual steering. Power
steering uses a hydraulic pump or electric motor to assist the driver`s effort.

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CONCLUSION
Industrial training is the way for us to get the practical knowledge of the entire theoretical
concept studied in college session. In college workshop we are not able to give proper time for
practical work as in industrial training. So as a Mechanical Engineering student I think this
training is very useful for us and we learn enough things in the training period and our
knowledge level will be increased.
We enjoy the training and maintain discipline in workshop and the entire mechanics are
impressed with our attitude and sense of learning and they give us best wishes for our future and
say that you must be hard work as an engineering student to make your future bright.
So, at last I would like to thanks once again to all workshop members, work manager and HOD
of Mech. Engg..

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BIBLIOGRAPHY
• Standard publisher’s distributors Dr. Kirpal Singh
• S. Chand publications R .S. Khurmi
• www.google.co.in
• Under the guidance of :
1) Mr. Rajender Singh Guleria (Regional Manager)
2) Workshop Manager