BLW summer training report in four weeks

1. VOCATIONAL TRAINING REPORT
AT
TECHNICAL TRAINING CENTRE
BANARAS LOCOMOTIVE WORKS
Varanasi – 221004, Uttar Pradesh (India)
SUBMITTED BY:
PRIYANSHU PAL
B.TECH – 3rd Year (Electrical Engineering )
Reg. No. – 2022061193
College – Prasad Institute Of Technology
Jaunpur – 222002
SUBMITTED AT:
Technical Training Centre
Banaras Locomotive Works
Varanasi, Uttar Pradesh – 221004

2. CONTENT
S.N. PARTICULARS
1 ACKNOWLEDGEMENT
2 PREFACE
3 INTRODUCTION OF BLW
4 HISTORY
5 TAS
6 MRS
7 LAS
8 COLONY

3. ACKNOWLEDGEMENT
Summer training has an important role in exposing the real-
life situation in an industry. It was a great experience for me to
work on training at BANARAS LOCOMOTIVE WORKSHOP
through which I could learn to work in a professional
environment.
I would sincerely like to thank the employees and the officers
of BLW, VARANASI for their help and support during the
vocational training. Despite their busy schedules, they took time
out for us and explained to us the various aspects of the working
of the plant from the production shops.
I would sincerely like to thank all the concerned engineers and
senior officials who was instrumental in arranging the vocational
training at BLW Varanasi, and without whose help and guidance
the training could not have materialize.
I express my deep sense of gratitude to Ramjanm Chaubey
Principal TTC, BLW for given me such a great opportunity.

4. PREFACE
The objectives of the practical training are to learn something about industries practically &
to be familiar with the working style of technical personto adjust simply according to the
industrial environment.
It rightly said practically life is far away from theoretical one. We learn in class room can
give the practical exposure or real life experience nodoubt they help in improving the
personality of the student, but the practical exposure in the field will help the student in
long run of life & will be able to implement the theoretical knowledge.
As a part of academic syllabus of four year degree course in Mechanical Engineering
.Every student is required to undergo a practical training.
I am student of Third year mechanical & this report is written on the basis of practical
knowledge acquired by me during the period of practical training taken at BANARAS
Locomotive Work, Varanasi

5. INTRODUCTION TO BLW
Banaras Locomotive Works (BLW) is a production unit under the ministry of
railways. This was setup in collaboration with American Locomotive
Company (ALCO), USA in 1961 and the first locomotive was rolled out in
1964. This unit produces diesel electronic locomotives and DG sets for Indian
railways and other customers in India and Abroad.
Subsequently a contract for transfer of technology of 4000 HP Microprocessor
Controlled AC/AC Freight (GT 46 MAC) / passenger (GT 46 PAC) locomotives
and family of 710 engines has been signed with electro motive division of
GENERL MOTORS for manufacture in BLW. The production of these
locomotives has now started and thus BLW is the only manufacturers of Electric
Locomotives with both ALCO and General Motors technologies in the world.

6. Brief History:
 Set up in 1961 as a green-field project in technical collaboration with
ALCO/USA to Manufacture Diesel Electric Locomotives.
 First locomotive rolled out and dedicated to nation in January, 1964.
 Transfer-of-Technology agreement signed with General Motors/ USA in
October, 95 to manufacture state-of-the-art high traction AC-AC diesel
locomotives.
 A flagship company of Indian Railways offering complete range of flanking
products in its area of operation.
 State-of-the art Design and Manufacturing facility to manufacture more than
150 locomotives per annum with wide range of related products viz.components and sub-assemblies.
 Unbeatable trail-blazing track record in providing cost-effective, eco-friendly
and reliable solutions to ever-increasing transportation needs for over three
decades.
 Fully geared to meet specific transportation needs by putting Price-Value-
Technology equation perfectly right.
A large base of delighted customers among many countries viz. Sri Lanka, Malaysia,Vietnam,
Bangladesh, Tanzania to name a few, bearing testimony to product leadership in its category.

7. PRODUCT OF BLW:
BLW is an integrated plant and its manufacturing facilities are flexible in nature. These can be utilized for manufacture of
different design of locomotives of various gauges suiting customer requirements and other products. The product range
available is as under:
 WDG4 4000 HP AC/AC Freight Traffic Locomotive
 WDP4 4000 HPAC/AC Broad Gauge High Speed
Locomotive
 WDG3D 3400 HP AC/AC Broad Gauge Mixed Traffic
Micro-Processor Controlled Locomotive.
 WDM3C 3300 HP AC/DC Broad Gauge Mixed Traffic
Locomotive.
 WDM3A 3100 HP AC/DC Broad Gauge Mixed Traffic
Locomotive.
 WDP3A 3100 HP AC/DC Broad Gauge High Speed
Passenger Locomotive.
 WDG3A 3100 HP AC/DC Broad Gauge Freight Locomotive.
 WDM2 2600 HP AC/DC Broad Gauge Mixed Traffic
Locomotive.
 WDP1 2300 HP AC/DC Broad Gauge Intercity Express
Locomotive.
 WDM7 2150 HP DC/DC Broad Gauge Mixed Traffic
Locomotive.
 WDM6 1350 HP DC/DC Broad Gauge Mixed Traffic
Locomotive.
 YDM4 1350 HP AC/DC & DC/DC Broad Gauge Mixed
traffic Locomotive.
 EXPORT LOCO 2300 HP AC/DC Meter Gauge/Cape gauge Mixed

8. Traffic Locomotive.
Diesel Generating Sets 800 KW to 2500 KW
Spare Parts for engines, locomotives and generating sets

9. TRACTION ASSEMBLY SHOP
Traction assembly shop is the unit in which all the locomotive parts are assembled that includes:
1. CP (Control Panel)
2. Alternator
3. Traction Motors
4. 16 cylinder Diesel Engine
5. Master Control
6. Cab
7. Auxiliary Generator & Excited
8. Governor
9. Crank Case Exhauster
10. Mechanical Assembly
Control Panel
The CP or the Control Panel (wrt WG3A loco) consists of:
a) Control Switch
b) Display Unit
c) LED Panel
d) Microprocessor based Control Unit
e) Reverser
f) BKT
g) Valves
h) Hooter
i) CK1/ CK2/ CK3
The top portion of CP has sensors and relays connected to the microprocessor unit. The display unit of
microprocessor shows working condition of items in engine (electrical equipments apart from engine). The
LED Panel displays the overload, auxiliary generator failure, hot engine, rectilinear fuse blown, etc. The
battery ammeter shows the charging state of the batteries. REV: Field wiring goes to reverser (REV) and
hence it is used to control the polarity of the field which in turn controls the direction of train. BKT: It is a
switch which in one direction is used to motor the loco while in other it is used for dynamic braking.
Microprocessor based Control Unit: On-board microprocessors control engine speed, fuel injection, and
excitation of the alternator. These computers also interconnect with improved systems to detect slipping or
sliding of the driving wheels, producing faster correction and improved adhesion. An additional function of the
microprocessor is to monitor performance of all locomotive systems, thereby increasing their reliability and

10. making the correction of problems easier. Hooter: It is a vigilance control device (VCD) to keep the driver
alert. If the driver isn‟t doing anything with the controls for over a minute, the hooter „hoots‟ and brings the
engine speed to the normal speed (low) without asking the driver. It can only be reset after 2 minutes and
hence the driver will be
held responsible for delay in reaching the next station.
Fig.2.1 Control Panel of WG3A loco
Dynamic braking
It is the use of the electric traction motors of a railroad vehicle as generators when slowing the vehicle. It is
termed rheostatic if the generated electrical power is dissipated as heat in brake grid resistors, and
regenerative if the power is returned to the supply line.
Dynamic braking lowers the wear of friction-based braking components, and additionally regeneration can
also lower energy consumption.
During braking, the motor fields are connected across either the main traction generator (diesel-electric loco)
or the supply (electric locomotive) and the motor armatures are connected across either the brake grids or
supply line. The rolling locomotive wheels turn the motor armatures, and if the motor fields are now excited,
the motors will act as generators.
For a given direction of travel, current flow through the motor armatures during braking will be opposite to
that during motoring. Therefore, the motor exerts torque in a direction that is opposite from the rolling
direction. Braking effort is proportional to the product of the magnetic strength of the field windings, times that
of the armature windings. In DLW Locomotives the braking method used is rheostatic, i.e. the traction motors
behave as generators (separately excited) and their electrical power is dissipated in brake grid resistors. This
method is used for minimising speed of the loco. The loco actually comes to a halt due to factors like air
resistance, friction with the rail, etc.
Alternator

11. An alternator converts kinetic energy (energy of motion) into electrical energy. All recently manufactured
automobiles rely on alternators to charge the battery in the ignition system and supply power to other
electrical equipment. Alternators are sometimes called AC generators because they generate alternating
current (AC).
Electric current can be generated in two ways: The magnet may rotate inside the coil, or the coil may rotate
in a magnetic field created by a magnet. The component that remains stationary is called the stator, and the
component that moves is called the rotor. In alternators, the coil is the stator and the magnet is the rotor. A
source of mechanical power, i.e. the diesel engine turns the rotor.
In WDM-3D and WDM-3A locos, the diesel engine‟s mechanical output is used to run the shaft of the
Alternator. The alternating output of the Alternator is then rectified to DC via solid-state rectifiers and is fed to
traction motors (DC) that run the loco wheels. Thus they operate on AC-DC Traction mechanism. WDG4
and WDP4 locos have AC-ACtraction with microprocessor control, i.e. AC Traction motors are used thus
eliminating the motor commutator and brushes The result is a more efficient and reliable drive that requires
relatively little maintenance and is better able to cope with overload conditions.
Why not feed direct DC to the traction motors via DC generators?
In a DC generator, the rotor is the coil. Alternators normally rotate the magnet, which is lighter than
the coil. Since alternators are built to spin the lighter component instead of 10
the heavier one, they generally weigh only one-third as much as generators of the same capacity. DC
generators, in particular, require more maintenance because of wear on the parts that brush against one
another in the commutator switch and the stress of rotating the heaviest component instead of the lightest.
Also, when generators are run at higher speeds, electricity tends to arc, or jump the gap separating metal
parts. The arcing damages parts and could make generators hazardous to touch. Alternators can run at high
speeds without arcing problems.
Fig.2.2 Alternator
Traction Motor
It‟s an electric motor providing the primary rotational torque of the engine, usually for conversion into linear
motion (traction).

12. Traction motors are used in electrically powered rail vehicles such as electric multiple units and electric
locomotives, other electric vehicles such as electric milk floats, elevators and conveyors as well as vehicles
with electrical transmission systems such as diesel-electric and electric hybrid vehicles. Traditionally, these
are DC series-wound motors, usually running on approximately 600 volts.
Fig.2.3 Traction motors
16 Cylinder Diesel Engine
It is an internal-combustion engine in which heat caused by air compression ignites the fuel. At the instant
fuel is injected into a diesel engine‟s combustion chambers, the air inside is hot enough to ignite the fuel on
contact. Diesel engines, therefore, do not need spark plugs, which are required to ignite the air-fuel mixture in
gasoline engines. The Diesel engine has 16 cylinders. Pistons inside the cylinders are connected by rods to
a crankshaft. As the pistons move up and down in their cylinders, they cause the crankshaft to rotate. The
crankshaft‟s rotational force is carried by a transmission to a drive shaft, which turns axles, causing
mechanical output. Eight 8V and four 2V Batteries are used in series to run a more powerful starter motor,
which turns the crankshaft to initiate igni-
tion in a diesel engine for the first time.
Fig.2.4 diesel engine of ALCO loco

13. Master Control
It‟s the unit that has the handles to regulate the speed of the loco as well as the direction of motion. It has
numbering from 0-9 and each increment causes rise in speed in forward direction. It can also be used to
reverse the direction of motion by pushing the handle in the opposite sense. It is present on the control desk
of the cab.
Cab
It‟s the driver‟s cabin with 2 control desks, the Control Panel (CP) and chairs for the driver. The Cab is at one
end of the locomotive with limited visibility if the locomotive is not operated cab forward. Each control desk
has the Independent SA9 brake for braking of the engine alone and Auto Brake A9 for the braking of the
entire loco. It also has the fol-
lowing components:
 LED Panel
 Buttons of various engine LED lights (front and side)
 Automatic sand throw button (to prevent sliding of wheels on inclined
tracks)
 Master Control Gauges to monitor booster air pressure and fuel & lube oil pressures.
Speedometer
 Service Brakes (Independent and Auto brakes described above) Emergency Brake (Type
of Air brake to halt the train in the distance nearly equal to the length of the train, to be used
only during an emergen-
cy)
Auxiliary Generator and Exciter
The Alternator has these two components. The exciter and the auxiliary generator consist of two armatures
on a single shaft. The auxiliary generator supplies a constant voltage of around 72V for supplying power to
charge the battery for the control equipment and to power the locomotive lights. The Exciter supplies
excitation for the main generator. Starting of Engine The supply from the batteries is given to the exciter. The
exciter has armature and field windings. Hence it starts rotating as it receives the supply voltage. The Exciter
is coupled with the rotor of the alternator which in turn is connected with the propeller shaft. When the
propeller rotates at a particular rpm, the
engine gets started. It‟s just like starting a bike. The „kick‟ must be powerful enough to start its engine. Later
the engine runs on diesel oil (fuel). As soon as the engine starts, the auxiliary generator also coupled with the
alternator starts charging the batteries. Its po-
tential is maintained at ~ 72V.

14. Fig .2.5 Auxiliary generator
Governor
It is the device that has the following functions:
1. To control engine speed
2. Deliver fuel (Diesel oil) according to load
3. To mediate electrical demand and diesel engine output.
Crank case exhauster
It is the device used to evacuate the diesel engine chamber.
Fig.2.6 Crank case
Mechanical Assembly
All mechanical parts on the engine apart from the above mentioned units may be
grouped in this category. It essentially consists of:
 Base frame Wheels
 Air Brakes Batteries
Sand Box Vacuum
brakes
 Fuel tank (Loco fuel oil tank
capacity is 3000L) etc

15. Air Braking System of Locomotives: On a train, the brake shoes are pressed directly against the wheel rim.
A compressor generates air pressure that is stored in air tanks.
Air hoses connect the brakes on all the train cars into one system. Applying air pressure into the system
releases the brakes, and releasing air pressure from the system applies the brack.

16. SUB 1 SUB
5
SUB
2
SUB
4
SUB
3
Generator
SUB
1
SUB
2
SUB
3
Generator
Main Receiving Substation (MRS)
MRS receives main supply from UPPCL at 33kv.
This is step down with 7.5MVA transformer. The 33kv feeder is transformedinto two 11kv feeder with a
bus coupler in between.
There are two types of distribution techniques:
1. Ring System- Under this system, each substation is connected to the
distribution system with two different transmission lines coming from the
MRS. Hence the substations receive power from any one of the lines.
2. Radial System-A single main line runs down the MRS and
varioussubstations are connected to it forming branches.

17.  The MRS follows the ring type distribution system for supplying power
to BLW. The advantage of ring type system is that each substation is fed
from two sides. If in case one line is faulted then the substation is fed by
other line. But major disadvantage of ring type system is that it is too
costly.
Safety Precautions at MRS: The most important responsibility while handlingsuch high power is safety
of the employees and equipments. The following measures are undertaken at MRS for protection-
1. Protection Relays:
i. Over Current Relay- It is set at the current limit of the device with lowest
current rating.
ii. Differential Relay- It prevents imbalance in current in different phases.
iii. Negative Phase Sequence Relay- It detects if the R-Y-B sequence is
putwrongly.
iv. Under/Over Voltage Relay
v. Reverse Power Relay- Prevents clashing of power from different sources.
2. Air Circuit Breaker (ACB) - Air Circuit Breaker is a device used to provide
overcurrent and Short Circuit Protection for circuits ranging from 800 Amps to
10000 Amps. One should not be confused between Air Circuit Breaker and Air
Blast Circuit Breaker. Air Circuit Breakers are usually used in low voltage
applications below 450 volts.

18. ACBs are being replaced by SF6 Circuit Breakers in a phased manner.
The gaseous medium SF6 possesses excellent dielectric and arc quenching properties.
After arc extinction, the dissociated gas molecules recombine almost completely to
reform SF6. This means that practically no loss/consumption of the quenching medium
occurs. The gas pressurecan bevery simply and permanently supervised. This function
is not needed where the interrupters are sealed for life.

19. Loco Assembly Shop
Tested engines are received from Engine Division. Similarly under-frames are
received fromLoco frame Shop and Assembled trucks from Truck Machine
Shop. Superstructures and contractor compartments are received from
respective manufacturing and assembly shops of Vehicle Division. Important
alignments like crank shaft deflection, compressor alignment and Eddy
Current clutch/radiator fan alignment are done during assembly stage.
Electrical control equipments are fitted and control cable harnessing is
undertaken. The complete locomotive is thus assembled before being sent
onwards for final testing and painting. All locomotive systems are rigorous
tested as per laid down test procedures before the locomotive is taken up for
final painting and dispatch for service

20. Operation in LAS
1. Drive cap assembly
Air compressor assembly
Control stand assembly
2. Driver cap checking
Air brake piping
3. Long hood assembly
Buffer assembly
Radiator setting
4. Engine setting
Compressor setting
5. Long hood setting
Auxiliary generator assembly and setting
Alternator part packing and assembly
6. Equipment assembly
Fuel oil parking Lube oil piping
Engine water cooling piping
7.Driver sheet setting
Damper assembly
Air duct setting

21. Colony
Introduction
Electricity transmission is the process of
transferring electrical energy to consumers.
Electrical energy generated at power facilities is
transmitted at high voltages through overhead
power lines and cables.Thosetransmission lines
connect to substationswhich transform the power
to lowervoltages for distribution to consumers
through the distribution system.
From the Power Station to the Home
Inside a generating station, turbines use the driving force of water to set electrons in motion
and generate alternating current.
Fig 4.1 Electricity transmition from the power station to customer
Electricity from the power station has a long way to go before reaching your home.
1. The voltage of the current produced by a generating station can reach 13,800 volts,
like at the Robert-Bourassa generating facility.
2. Thanks to the voltage step-up transformer located in the generating station‟s
switchyard, the electricity is transmitted at much higher voltages, from 44,000 to
765,000 volts.

22. 3. Once in the transmission system, electricity from each generating station is
combined with electricity produced elsewhere.
4. The electricity passes through cables which are suspended from towers. These
towers are arranged in a series from the generating stations to source substations–
which lower the voltage–and then reach the satellite substations, which further
reduce the voltage.
5. Leaving the satellite substations, electricity travels through underground lines. At
some distance from the substations, the distribution system goes from underground
to overhead, and transformers attached to poles lower the voltage one last time.
Inside our homes, we use either 120 volts to power our televisions, radios and other
regular electrical appliances, or 240 volts for the appliances that require a strong
current like the
dryer or stove.
6. Electricity is consumed as soon as it is produced. It is transmitted at a very high
speed, close to the speed of light (300,000 km/s).
Electrical substation model (side-view)
Fig: 4.2 1.Primary power lines 2.Ground wire 3.Overhead lines 4.Lightning arrester
5.Disconnect switch 6.Circuit breaker 7.Current transformer 8.Transformer for
measurement of electric voltage 9.Main transformer 10.Control building 11.Security
fence 12.Secondary power lines
Elements of a substation
Substations generally have switching, protection and control equipment, and
transformers. In a large substation, circuit breakers are used to interrupt any short
circuits or overload currents that may occur on the network. Smaller distribution stations
may use recloser circuit breakers or fuses for protection of distribution circuits. Substations
themselves do not usually have generators, although a power plant may have a substation
nearby. Other devices such as capacitors and voltage regulators may also be located at a
substation.
Substations may be on the surface in fenced enclosures, underground, or located in

23. specialpurpose buildings. High-rise buildings may have several indoor substations. Indoor
substations are usually found in urban areas to reduce the noise from the transformers, for
reasons of appearance, or to protect switchgear from extreme climate or pollution
conditions.
Where a substation has a metallic fence, it must be properly grounded to protect people
from high voltages that may occur during a fault in the network. Earth faults at a substation
can cause a ground potential rise. Currents flowing in the Earth's surface during a fault can
cause metal objects to have a significantly different voltage than the ground under a
person's feet; this touch potential presents a hazard of electrocution
Step-up and Step-down Transformers
This is a very useful device, indeed. With it, we can easily multiply or divide voltage and
current in AC circuits. Indeed, the transformer has made long-distance transmission of
electric power a practical reality, as AC voltage can be “stepped up” and current “stepped
down” for reduced wire resistance power losses along power lines connecting generating
stations with loads. At either end (both the generator and at the loads), voltage levels are
reduced by transformers for safer operation and less expensive equipment. A transformer
that increases voltage from primary to secondary (more secondary winding turns than
primary winding turns) is called a step-up transformer. Conversely, a transformer designed
to do just the opposite is called a step-down transformer.
Step-up and step-down transformers for power distribution purposes can be gigantic in
proportion to the power transformers previously shown, some units standing as tall as a
home. The following photograph shows a substation transformer standing about twelve feet
tall.
Fig 4.3 (a)Substation transformer. Fig 4.3 (b) Block diagram

24. REVIEW:
∑ Transformers “step up” or “step down” voltage according to the ratios of primary to
secondary wire turns.
∑ A transformer designed to increase voltage from primary to secondary is called a step-up
transformer. A transformer designed to reduce voltage from primary to secondary is
called a step-down transformer.
∑ The transformation ratio of a transformer will be equal to the square root of its primary to
secondary inductance (L) ratio.
∑
By being able to transfer power from one circuit to another without the use of
interconnecting conductors between the two circuits, transformers provide the useful
feature of electrical isolation.
Transformers designed to provide electrical isolation without stepping voltage and
current either up or down are called isolation transformers.
BUSBARS
It an electrical conductor, maintained at a specific voltage and capable of carrying a high
current, usually used to make a common connection between several circuits in a
system
When numbers of generators or feeders operating at the same voltage have to be
directly connected electrically, bus bar is used as the common electrical component. Bus
bars are made up of copper rods operate at constant voltage. The following are the
important bus bars arrangements used at substations:
∑ Single bus bar system
∑ Single bus bar system with section alisation.

25. ∑ Duplicate bus bar system
In large stations it is important that break downs and maintenance should interfere as
little as possible with continuity of supply to achieve this, duplicate bus bar system is
used. Such a system consists of two bus bars, a main bus bar and a spare bus bar with
the help of bus coupler, which consist of the circuit breaker and isolator.
In substations, it is often desired to disconnect a part of the system for general
maintenance and repairs. An isolating switch or isolator accomplishes this. Isolator
operates under no load condition. It does not have any specified current breaking
capacity or current making capacity. In some cases isolators are used to breaking
charging currents or transmission lines.
While opening a circuit, the circuit breaker is opened first then isolator while closing a
circuit the isolator is closed first, then circuit breakers. Isolators are necessary on supply
side of circuit breakers, in order to ensure isolation of the circuit breaker from live parts
for the purpose of maintenance.
A transfer isolator is used to transfer main supply from main bus to transfer bus by using
bus coupler (combination of a circuit breaker with two isolators), if repairing or
maintenance of any section is required.