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L.R.INSTITUTE OF ENGINEERING AND
TECHNOLOGY
DEPARTMENT OF MECHANICAL ENGINEERING
INDUSTRIAL TRAINING REPORT
H.R.T.C. DHARAMSHALA
July-August 2015
Submitted by: Submitted to:
Koushik Bibra Gurpreet Singh Virk(Roll No.) BTL-302183 (Training-In Charge) Semester-7th
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ACKNOWLEDGEMENT
It gives me immense pleasure to express my deepest sense of gratitude and
sincere thanks to my highly respected and esteemed guide Mr. Vinod Sharma
LRIET, SOLAN for their valuable guidance, encouragement and help for
completing this work. Their useful suggestions for this whole work and co-
operative behavior are sincerely acknowledged.
I also wish to express my gratitude to Mr. Yadwinder Singh HOD (Mechanical
Engineering)for his kind hearted support. I am also grateful to my teachers Mr.
Gurpreet Singh Virk for their constant support and guidance.
I also wish to express my indebtedness to my parents as well as my family
member whose blessings and support always helped me to face the challenges
ahead.
At the end I would like to express my sincere thanks to all my friends and others
who helped me directly or indirectly during this project work.
Place: Solan Koushik bibraDate: Roll No. BTL-302183
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ABSTRACT
In my industrial training, I was introduced to industrial environment. I learned
discipline and cooperation during my industrial training and I felt good when I
came in contact with engineers and workers of workshop. Most importantly I had
learned the process of doing work in big workshops with complete knowledge of
Engine Shop and Gear Shop which will be useful for me whenever I will go to any
industry or workshop as an employee.
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1. INTRODUCTION OF H.R.T.C DHARAMSHALA
1. All having new technology multi cylinder engine.
2. There is timely checking of the engine performance.
3. All engine all of different technology and series i.e. of EURO 4
series.
4. The buses are checked after every routs.
2. MAIN PARTS OF AUTOMIBLEPage | 4
1. Chassis
2. Engine
3. Gear box
4. Clutch
5. Differential
6. Propeller shaft
7. Suspension system
8. Brake
9. Wheel
3. CHASSIS:- The rectangular, usually steel frame, supported on springs and attached to
the axles, that holds the body and motor of anautomotive vehicle.
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The landing gear of an aircraft, including the wheels, skids, floats, and other structures that support the aircraft on land or water.
The frame on which a carriage moves forward and backward.
The framework to which the components of engine, gear box suspension system are attached.
Figure 3.1 chassis
4. INTRODUCTION OF ENGINE: -
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4.1 ENGINE: -
An engine is a machine designed to convert one form of energy into mechanical energy. Heat engines, including internal combustion engines and external combustion engines (such as steam engines) burn a fuel to create heat, which then creates a force. Electric motors convert electrical energy into mechanical motion, pneumatic motors use compressed air and others—such as clockwork motors in wind-up toys—use elastic energy. In biological systems, molecular motors, use chemical energy to create forces and eventually motion.
Figure 4.1 Engine
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4.2 TYPES OF ENGINES:-
The engines of basically are two types
1. Internal combustion engine
2. External combustion engine
The engines used in the buses are commonly internal combustion types. In
which the air is sucked from the atmosphere, compressed by the turbo and then
send to combustion chamber.
The air is so compressed and temperature of air raised to some critical point,
when the spray of the selected quantity of diesel introduce to this hot
compressed air then it caught the fire and burn with a blast.
This gives a push to the piston and process proceed an action, mean the
connecting rod transmitted the power to the crank shaft and then
This power is to the crank shaft and then this power is to the wheels of the
vehicles through propeller shaft.
Gives a turn to the fly wheel which further initiates the intakes process.But the
concept a little change here so that the driver turn the key to start the engine the
self which is so connected to the battery, it gives to the self-starter. Then it in this
way engine start the working.
4.3 MAIN PARTS OF ENGINE
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The whole assembly of an engine is as its own importance at the time, but from
the working mechanism point of view there are the main parts are given below:
1. ENGINE CYLINDER
2. BORE
3. PISTON
4. CONNECTING ROAD
5. CRANK SHAFT
6. CRANK PIN
7. CAM SHAFT
8. INLET&OUTLET VALVES
9. NOZZELE
10.TURBO
11.F.I.PUMP
5. TRANSMISSION SYSTEM
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Transmission system is the most important object and point in the Automobile
industry. This deals with the power transmission and performance of the vehicle
over the road. The main objects of the transmission are as given below:-
1. Clutch
2. Clutch plate
3. Gear box
4. Propeller shaft
5. Differential
5.1 CLUTCH:-
A clutch is a mechanical device that engages and disengages the power transmission, especially from driving shaft to driven shaft.
Clutches are used whenever the transmission of power or motion must be controlled either in amount or over time (e.g. electric screwdrivers limit how much torque is transmitted through use of a clutch; clutches control whether automobiles transmit engine power to the wheels).
In the simplest application, clutches connect and disconnect two rotating shafts (drive shafts or line shafts). In these devices, one shaft is typically attached to an engine or other power unit (the driving member) while the other shaft (the driven member) provides output power for work. While typically the motions involved are rotary, linear clutches are also possible.
In a torque-controlled drill, for instance, one shaft is driven by a motor and the other drives a drill chuck. The clutch connects the two shafts so they may be locked together and spin at the same speed (engaged), locked together but spinning at different speeds (slipping), or unlocked and spinning at different speeds.
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Figure 5.1 Clutch housing
5.2 GEAR BOX:-
A transmission is a machine that consists of a power source and a power transmission system, which provides controlled application of the power. Often the term transmission refers simply to the gearbox that uses gears and gear
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trains to provide speed and torque conversions from a rotating power source to another device.
5.2.1 TYPES OF GEAR BOX:-1. Sliding mesh gear box.2. Constant mesh gear box.3. Synchromesh gear box.
5.2.2 SLIDING MESH GEAR BOX:-A sliding-mesh gear box is similar to a constant-mesh gearbox, but differs in the way the individual gears are engaged. In the sliding-mesh gearbox, the individual gear ratio is chosen by sliding the selected gearwheel axially along the splined main output shaft until it meshes fully with the corresponding lay shaft gear cluster. The sliding main shaft gearwheels and their corresponding lay-shaft gearwheel clusters have to be of the spur straight-tooth form, so that when engaged there is no side thrust unlike helical-cut teeth. The major problem with this type of gear engagement is that, while attempting a gear change, the speeds of the input and output shafts are matched first, otherwise the sliding teeth of the mashing gearwheels does not align and hence crashes into each other.Transmission shafts and gears are generally manufactured using low-alloy nickel-chromium-molybdenum steels. This type of gearbox is presently used only in certain commercial vehicles where a large number of close gear ratios are required in a compact form.
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Figure 5.2.Sliding mesh gear box
5.2.3 CONSTANT MESH GEAR BOX:-In this type of gearbox, all the gears of the main shaft are in constant mesh with the corresponding gears of the counter shaft or lay shaft.
Two dog clutches are provided on the main shaft i.e. one in between the clutch gear and the second gear, and the other between the first gear and the reverse gear.
The dog clutch can slide on the shaft and rotate with it. While, all the gears on the counter shaft are rigidly fixed with it.
As and when the left hand dog clutch is made to slide to the left by means of the gear shift lever, it meshes with the clutch gear and the top speed gear is obtained. When the left hand dog clutch meshes with second gear, the second gear is obtained.
Similarly, by sliding right hand dog clutch to the left and right, the first speed gear and reverse gear are obtained respectively.
In this type of gearbox, all the gears are in constant mesh and hence for this reason, they are safe from being damaged and irritating grinding sound does not occur while engaging and disengaging.
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Figure 5.3 Constant mesh gear box
5.2.4 SYNCHROMESH GEAR BOX:-Synchromesh gearbox is an extension of constant mesh type gearbox.
Synchromesh type of gearbox is used over constant type of gearbox because constant mesh type suffers from the problem of clashing of dog clutch due to large difference in speeds of engaging gears.Synchromesh gears ensure initial frictional contact amongst mating parts of gears to equalize speed of gears pair and then push for smooth engagement of dog clutch with gear on main shaft.
Figure 5.4 Synchromesh gear box.
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6. PROPELLER SHAFT:-
Propeller shaft connects gearbox to the final drive gears of the vehicle through
universal joint and serves as drive shaft. A universal joint allows the drive to be
transmitted through a variable angle. The drive system is an arrangement for
transmitting the driving thrust from the road wheels to the vehicle body. The final
drive is the transmission system between propeller shaft and differential. The
differential mechanism is built into the center portion of the final drive. This
permits the wheels to rotate at different speeds without interfering with the
propulsion of the vehicle while taking a turn. In case of rear wheel drive, the rear
axle is “live”, which in addition to support the weight of the vehicle contains a
gear and shaft mechanism to drive the road wheels. The chapter deals all these
subsystems for a rear wheel drive system. Also it presents briefly front-wheel
drive and four-wheel drive systems.
Figure 6.1 propeller shaft
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7. DIFFERENTIAL:-
Differential gear, in automotive mechanics, gear arrangement that permits power
from the engine to be transmitted to a pair of driving wheels, dividing the force
equally between them but permitting them to follow paths of different lengths, as
when turning a corner or traversing an uneven road.On a straight road the
wheels rotate at the same speed; when turning a corner the outside wheel has
farther to go and will turn faster than the inner wheel if unrestrained.
A differential is a particular type of simple planetary gear train that has the
property that the angular velocity of its carrier is the average of the angular
velocities of its sun and annular gears. This is accomplished by packaging the
gear train so it has a fixed carrier train ratio R = -1, which means the gears
corresponding to the sun and annular gears are the same size. This can be done
by engaging the planet gears of two identical and coaxial epicycle gear trains to
form a spur gear differential. Another approach is to use bevel gears for the sun
and annular gears and a bevel gear as the planet, which is known as a bevel
gear differential.
Figure 7.1 Differential
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8. BRAKES:-
A brake is a mechanical device which inhibits motion. The rest of this article is
dedicated to various types of vehicular brakes.
Most commonly brakes use friction to converted kinetic energy into heat, though
other methods of energy conversion may be employed. For example
regenerative braking converts much of the energy to electric energy, which may
be stored for later use. Other methods of converted kinetic energy to potential
energy in such stored form as pressurized oil. Eddy current brakes use magnetic
field to convert kinetic energy into electric energy in the brake disc, fin, or rail,
which is converted into heat. Still other braking methods even transform kinetic
energy into different forms, for example by transferring the energy to a rotating
flywheel.
Brakes are generally applied to rotating axles or wheels, but may also take other
form such as the surface of the mo9ving field. Some vehicle use a combination of
braking mechanism, such as drag racing cars with both wheel brakes and a
parachute or air planes with both wheel brakes and drag flats raised in to the air
during landing.
8.1 Types of Brakes:-
Brakes are one of the most important safety features on your vehicle. There are
different types of brakes, both between vehicles and within a vehicle. The brakes
used to stop a vehicle while driving are known as the service brakes, which are
either a disc and drum brake. Vehicles also come equipped with other braking
systems, including anti-lock and emergency brakes.
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8.1.1Drum Brakes
Drum brakes consist of a brake drum attached to the wheel, a wheel cylinder,
brake shoes, and brake return springs. Hydraulic pressure from the master
cylinder causes the wheel cylinder to press the brake shoes against the brake
drum. This creates friction between the shoes and drum to slow or stop your car.
Figure 8.1.drum brake
8.1.2 Emergency Brakes:-
Vehicles also come equipped with a secondary braking system, known as
emergency or parking brakes. Emergency brakes are independent of the service
brakes, and are not powered by hydraulics. Parking brakes use cables to
mechanically apply the brakes (usually the rear brake). There are a few different
types of emergency brakes, which include: a stick lever located between the
driver and passenger seats; a pedal located to the left of the floor pedals; or a
push button or handle located somewhere near the steering column. Emergency
brakes are most often used as a parking brake to help keep a vehicle stationary
while parked. And, yes, they are also used in emergency situations, in case the
other brake system fails!
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9. SUSPENTION SYSTEM:-
1. The purpose of the complete suspension system is to isolate the vehicle body from road shocks and vibrations which would otherwise be transferred to the passengers and load. It must also keep the tires in contact with the road, regardless of road surface.
2. A basic suspension system consists of springs, axles, shock absorbers, arms, rods, and ball joints.
3. The spring is the flexible component of the suspension. Basic types are leaf springs, coil springs, and torsion bars. Modern passenger vehicles usually use light coil springs.
4. Light commercial vehicles have heavier springs than passenger vehicles, and can have coil springs at the front and leaf springs at the rear.
5. Heavy commercial vehicles usually use leaf springs, or air suspension.6. Solid, or beam, axles connect the wheels on each side of the vehicle. This
means the movement of a wheel on one side of the vehicle is transferred to the wheel on the other side.
7. With independent suspension, the wheels can move independently of each other, which reduces body movement. This prevents the other wheel being affected by movement of the wheel on the opposite side, and this reduces body movement.
Figure 9.1 leaf sprig
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10. STEERING SYSTEM:-
The steering system converts the rotation of the steering wheel into a swiveling
movement of the road wheels in such a way that the steering-wheel rim turns a
long way to move the road wheels a short way.
The steering effort passes to the wheels through a system of pivoted joints.
These are designed to allow the wheels to move up and down with
the suspension without changing the steering angle.
They also ensure that when cornering, the inner front wheel - which has to travel
round a tighter curve than the outer one - becomes more sharply angled.
The joints must be adjusted very precisely, and even a little looseness in them
makes the steering dangerously sloppy and inaccurate.
10.1 TYPES OF STEERING SYSTEM:-
1. Rack and pinion steering.
2. Power steering.
10.1.1RACK AND PINION STEERING:-
At the base of the steering column there is a small pinion (gear wheel) inside a
housing. Its teeth mesh with a straight row of teeth on a rack - a long transverse
bar.
Turning the pinion makes the rack move from side to side. The ends of the rack
are coupled to the road wheels by track rods.
This system is simple, with few moving parts to become worn or displaced, so its
action is precise.
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A universal joint in the steering column allows it to connect with the rack without
angling the steering wheel awkwardly sideways.
Figure 10.1 Mechanism of rack and pinion
10.1.2 POWER STEERING:-
Power steering (also power assisted steering (PAS) or steering assist system)
helps drivers steer by augmenting steering effort of the steering wheel. Hydraulic
or electric actuators add controlled energy to the steering mechanism, so the
driver needs to provide only modest effort regardless of conditions. Power
steering helps considerably when a vehicle is stopped or moving slowly.In other
power steering systems, electric motors provide the assistance instead of
hydraulic systems. As with hydraulic types, power to the actuator (motor, in this
case) is controlled by the rest of the power-steering system.
Figure 10.2 Mechanism of power steering system
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11. CONCLUSION & FUTURE SCOPE
Conclusion:-
In this session of industrial training I was introduced to industrial environment. I
learned discipline and cooperation during training and I felt good when I came in
contact with engineers and workers.
Most importantly I have learned the process of doing work in big workshop with
complete knowledge.
Future Scope:-
One As I have gained lots of knowledge and technical skill in this particular time of six week. This will help me a lot in future.
Because with the theoretical knowledge, the practical and industrial experience is must and we gain lots in the technical and industrial environment. We can implement this knowledge further in different kinds of research and different individual works. There are lots of scopes of this particular time of six weeks in future.
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12. REFERENCES
1. HRTC Workshop Manual2. Automobile engineering book by Dr. Kirpal Singh , standard publishers
distributors.3. Automotive technology by H.M Sethi ,Tata McGraw Hill.4. Automobile engineering by Anil chhikara satyaprakashan , New Delhi.5. Wikipedia encyclopedia (date 20/09/2015 , time 08:00 pm).6. Theory of machines by S.S Rattan publishers Tata McGraw Hill.
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