The document summarizes the key activities and learnings from the author's internship at Diesel Traction Training Centre. The internship involved working on and inspecting various components of locomotive air brake systems to verify they met specifications. This provided hands-on experience with instruments like single and twin pipe braking systems. It was a valuable learning experience that helped apply theoretical knowledge to practical problems in an industrial setting. The internship also provided insight into industry expectations and prepared the author for future career opportunities in the mechanical field.

1. ABSTRACT
An internship is an opportunity for application of theoretical knowledge for a student. It
helps a student to identify problems, analyse them using the theories he has learned in
classrooms and often find the solutions for it. The industry work a lot different than what
is taught in the classrooms. They expect the smartest, toughest and strongest students.
Students are given a mere glimpse in their textbooks. The tip of the iceberg. What lies
underneath is much bigger than a student can actually comprehend or apprehend.
Industry training is what a student requires. It helps him to focus and apply the
knowledge he has gained. Industry often help students to apply their knowledge in ways
they would not have even imagined. Students are on their feet always in an industry.
They have to be quick thinking, aptitude sturdy, and be able to utilise the bookish
knowledge for real life problems.
My internship at DIESEL TRACTION TRAINING CENTR has been very helpful to me
in many ways. The following report is a mere glimpse of my time there and the ways it
has helped me. The report outlines the knowledge I have gained and the practical
experience I was able to reap from my days working as an intern.

2. TABLE OF CONTENTS
1. History of locomotive workshop
2. Air brake concept
a) Single pipe braking system
b) Twin pipe braking system
3. Loco brake system
a) A-9 Automatic brake valve
b) SA-9 Independent brake valve
c) Relay air valve
d) Distributor valve
e) Control valve
f) Emergency valve
4. Internship activities
5. Acknowledgements
6. Conclusion

3. History of locomotive workshops
Jamalpur Locomotive Workshop was established on 8
February 1862. Jamalpur Workshop was the first full-
fledged railway workshop facilities in India, set up by
the East Indian Railway. ... And then Jamalpur
Workshop was established at Jamalpur.
Northern Railway, the Jewel Set in the Crown of Indian Railways, has
embarked on the mission to vanquish distances and create its own
metaphor of existence. Formally established in the year 1952, it remains
the largest zone in terms of route Kilometers, even after the re-
organization of the Indian Railways into 16 zones. Northern Railway now
comprises of 5 Divisions-Ambala, Delhi, Ferozpur, Lucknow and
Moradabad.
Get-aways on Northern Railway
a) Jammu
b) Amritsar
c) Ludhiana
d) Chandigarh
e) Shimla
f) Moradabad
g) Delhi
h) Lucknow
i) Dehradun
j) Pathankot
k) Haridwar

4. The Workshops of Progress
• Locomotive Workshop, Charbagh.
• Carriage & Wagon Workshop, Alambagh.
• Carriage & Wagon Workshop,Jagadhari
• Carriage & Wagon Workshop, Kalka.
• Bridge Workshop, Jalandhar Cantt.
• Bridge Workshop, Lucknow.
• Engineering workshop, Jalandhar.
• Signal & Telecom Workshop, Ghaziabad.

5. Air brake concept
The air brake is the standard, fail-safe, train brake used by
railways all over the world. In spite of what you might think,
there is no mystery to it. It is based on the simple physical
properties of compressed air. So here is a simplified description
of the air brake system.
The Principal Parts of the Air Brake System
Compressor
The pump which draws air from atmosphere and compresses it for
use on the train. Its principal use is for the air brake system, although
compressed air has a number of other uses on trains.
Main Reservoir
Storage tank for compressed air for braking and other pneumatic
systems.
Driver's Brake Valve

6. The means by which the driver controls the brake. The brake valve
will have (at least) the following positions: "Release", "Running",
"Lap" and "Application" and "Emergency". There may also be a "Shut
Down" position, which locks the valve out of use.
Feed Valve
To ensure that brake pipe pressure remains at the required level, a
feed valve is connected between the main reservoir and the brake
pipe when the "Running" position is selected. This valve is set to a
specific operating pressure. Different railways use different pressures
but they generally range between 65 and 90 psi (4.5 to 6.2 bar).
Equalizing Reservoir
This is a small pilot reservoir used to help the driver select the right
pressure in the brake pipe when making an application. When an
application is made, moving the brake valve handle to the 17
application position does not discharge the brake pipe directly, it lets
air out of the equalizing reservoir.
Brake Pipe
The pipe running the length of the train, which transmits the variations
in pressure required to control the brake on each vehicle. It is
connected between vehicles by flexible hoses, which can be
uncoupled to allow vehicles to be separated. The use of the air
system makes the brake "fail safe", i.e. loss of air in the brake pipe
will cause the brake to apply. Brake pipe pressure loss can be
through a number of causes as follows:
1. A controlled reduction of pressure by the driver.
2. A rapid reduction by the driver using the emergency position on his
brake valve.
3. A rapid reduction by the conductor (guard) who has an emergency
valve at his position.
4. A rapid reduction by passengers (on some railways) using an
emergency system to open a valve.
5. A rapid reduction through a burst pipe or hose.
6. A rapid reduction when the hoses part as a result of the train
becoming parted or derailed.
Angle Cocks

7. At the ends of each vehicle, "angle cocks" are provided to allow the
ends of the brake pipe hoses to be sealed when the vehicle is
uncoupled. The cocks prevent the air being lost from the brake pipe.
Coupled Hoses
The brake pipe is carried between adjacent vehicles through flexible
hoses. The hoses can be sealed at the outer ends of the train by
closing the angle cocks.
Brake Cylinder
Each vehicle has at least one brake cylinder. Sometimes two or more
are provided. The movement of the piston contained inside the
cylinder operates the brakes through links called "rigging". The
rigging applies the blocks to the wheels. Some modern systems use
disc brakes. The piston inside the brake cylinder moves in
accordance with the change in air pressure in the cylinder.
Brake Block
This is the friction material which is pressed against the surface of the
wheel tread by the upward movement of the brake cylinder piston.
Often made of cast iron or some composition material, brake blocks
are the main source of wear in the brake system and require regular
inspection to see that they are changed when required.
Brake Rigging
This is the system by which the movement of the brake cylinder
piston transmits pressure to the brake blocks on each wheel. Rigging
can often be complex, especially under a passenger car with two
blocks to each wheel, making a total of sixteen.
Triple Valve
The operation of the brake on each vehicle is controlled by the "triple
valve", so called because it originally comprised three valves - a
"slide valve", incorporating a "graduating valve" and a "regulating
valve". It also has functions - to release the brake, to apply it and to
hold it at the current level of application.
The triple valve is now usually replaced by a distributor - a more
sophisticated version with built-in refinements like graduated release.
Two Pipe Systems

8. A problem with the design of the standard air brake is that it is
possible to use up the air in the auxiliary reservoir more quickly
than the brake pipe can recharge it. Many runaways have resulted
from overuse of the air brake so that no auxiliary reservoir air is
available for the much needed last application. The problem can
be overcome with a two-pipe system as shown in the simplified
diagram below.
The second pipe of the two-pipe system is the main reservoir pipe.
This is simply a supply pipe running the length of the train which is
fed from the compressor and main reservoir. It performs no control
function but it is used to overcome the problem of critical loss of
pressure in the auxiliary reservoirs on each car. A connecting pipe,
with a one-way valve, is provided between the main reservoir pipe
and the auxiliary reservoir. The one-way valve allows air from the
main reservoir pipe to top up the auxiliary reservoir. The one-way
feature of the valve prevents a loss of auxiliary reservoir air if the
main reservoir pressure is lost.
Another advantage of the two-pipe system is its ability to provide a
quick release. Because the recharging of the auxiliaries is done by
the main reservoir pipe, the brake pipe pressure increase which
signals a brake release is used just to trigger the brake release on
each car, instead of having to supply the auxiliaries as well.
Two pipe systems have distributors in place of triple valves. One feature of
the distributor is that it is designed to restrict the brake cylinder pressure

9. so that, while enough air is available to provide a full brake application,
there isn't so much that the brake cylinder pressure causes the blocks to
lock the wheels and cause a skid. This is an essential feature if the auxiliary
reservoir is being topped up with main reservoir air, which is usually kept at
a higher pressure than brake pipe air.
Self Lapping Brake Valves
Self lapping is the name given to a brake controller which is position
sensitive, i.e. the amount of application depends on the position of
the brake valve handle between full release and full application. The
closer the brake handle is to full application, the greater the
application achieved on the train. The brake valve is fitted with a
pressure sensitive valve which allows a reduction in brake pipe
pressure according to the position of the brake valve handle selected
by the driver. This type of brake control is popular on passenger
locomotives.
LOCO BRAKE SYSTEM
Loco brake system is provided to stop the Locomotive, whenever it
runs as light engine. It is purely compressed air brake system known
as independent brake system. For this separate air circuit is provided
in 28LAV-1 & IRAB-1 Brake system which is independent to other air
circuit. SA9 Independent brake valve is provided in driving control
stand for application & release of loco brake. Valve has three
positions i.e. Quick release, release and application.
a)A-9 automatic brake valve
The A9 Automatic Brake Valve maintains 5kg/cm2-air pressure in Brake
Pipe System against normal leakage at its release position. It also maintains
air pressure drop in the system according to its handle position.

10. b)SA-9 independent brake valve
SA-9 Independent Brake Valve is a compact self-lapping, pressure
maintaining Brake Valve which is capable of graduating the
application or release of Locomotive Air Brakes independent of
Automatic Brake. The SA-9 Independent Brake Valve is also capable
of releasing an automatic brake application on the Locomotive
without affecting the train brake application. The SA-9 Brake Valve
has three positions: quick release, release and application.
c)Relay air valve
The C2W Relay Air Valve is a diaphragm cooperated self-lapping valve
having higher capacity which is used as a remote controlled pneumatic
device to relay a large quantity of main air reservoir pressure to the
operating system for brake application.
d)Distributor valve

11. C3W Distributor Valve is a graduated release UIC approved Distributor
Valve for application in the Coach Brake System used for initiating the
brake application. These valves are supplied in Aluminium version as well as
Cast Iron version as far as Body, Top covers and Bottom Covers are
concerned.
e)Control valve
The VA-1B Control Valve proportions the amount of vacuum in the vacuum
brake pipe to the air pressure in the compressed air brake pipe on the
locomotive and acts as a pilot valve to operate the train vacuum brake, thus
securing an application simultaneously with, and in proportion to the
locomotive air brake application.
f)Emergency valve

12. The D-1 Emergency Brake Valve is a manually operated device which
provides a means of initiating an emergency brake application. When it is
desired to make the shortest possible stop, the brake valve handle is
moved to Emergency position, causing an emergency rate of brake pipe
reduction.

13. INTERNSHIP ACTIVITIES
The following is a summary of my activities during the internship period at DIESEL
TRACTION TRAINING CENTRE.
The job assigned to me was to work on air brake system. I was to inspect and verify
the work was according to the specifications laid down by the manual and by
engineers. During the period I was trained quite well by the engineers at Diesel
Traction Training Centre.
I was able to learn a lot about the different activities happening in a Diesel Traction
Training Centre. The observation of daily activities helped me glean a huge insight
into the intricacies of the workings. As my job title suggested, I was working on air
brake and had the ardurous task of inspecting the different work done in the company.
This helped me actually witness many of the works I had only been able to study
theoretically.
I was able to learn about the different instruments used in air brake system. A few of
the instruments are single pipe braking system,twin pipe braking system,A-9,SA-9
brakes, etc.
The main job was to verify the work was according to the drawing given by the
manual and guided by the engineers. I was to check the various dimensions and verify
the position of the work. This helped me learn a lot about practical knowledge of
using different types of valves in different fields.

14. ACKNOWLEDGEMENTS
My internship at Diesel Traction Training Centre from….. to ……. 2017 was a
memorable one. First of all I would like to express my deepest gratitude to the Principal
and Engineers of training centre for helping me and guiding me through the vast maze of
industrial work. Through their continuous support and encouragement I was able to learn
a lot as well put into practice my theoretical knowledge. I was able to learn more about an
industry and also I was initiated into the everyday operation of an industry.
I also would like to thank …college…… for including such Internships in their
curriculum and giving me this opportunity. I would like to thank the
………………………………………….. for their constant support and encouragement. It
would not have been possible without the help of god almighty.
This internship was a big milestone in my career development and I will strive to use this
skills and knowledge in the best possible way.
Words are very few to express my humble obligation to all who provided a helping hand
in this learning experience.

15. CONCLUSION
The internship I did at Diesel Traction Training Centre from ….. 2017 to …… 2017 was
very helpful and informative. I was able to learn in depth the working of industries and
their procedures. I also was able to understand the practical aspects of the theories I had
studied in college and also to identify and analyze a problem using the theories learned in
college. I also was able to understand what industries were looking for in new candidates.
FUTURE SCOPE
The knowledge gained through this internship will be cherished forever. I also am
grateful for the training received from Diesel Traction Training Centres as this has
prepared me for starting my journey into the world of mechanical industry. I also am
happy as I will be getting further training from Diesel Traction Training Centre as they
were quite satisfied with my performance and with my interest in learning new things and
utilizing it.