shakurbasti diesel shed report new

5/26/2018 Shakurbasti Diesel Shed Report New

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Industrial visit to Diesel Shed

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Industrial Visit ReportDiesel Loco Shed-- Shakurbasti

Submitted by ::

Mayank Sharma (631/MP/06)


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ACKNOWLEDGEMENT

We are grateful to Mr.Pradeep Khanna for making this visit to

Diesel Shed possible and for accompanying us on this visit and

also solving our various queries.

We are also thankful to the professionals the Shakurbasti Diesel

Shed for helping us know and understand the various

locomotives their principles and operations.


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Index

Details About Diesel Shed .4

Diesel Locomotives....5

The Classification Syntaxes7

WDM 2 locomotive.9

WDS 4 locomotive..12

Starting the WDM 2 locomotive...13

Diesel Hydraulic Transmission.15

Torque Converter15

Diesel Electric Transmission.16

Throttle Converter...16

Main Alternator.18

Motor Blower.18

Compressed Air System..19

Batteries.19

Lubrication.20

Dynamic Brakes.21

Air Brakes23

Testing at Diesel Shed24


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Details About the Diesel Shed

It is the pioneer WDS4 Loco shed of Northern Railway and came intoexistence on 5

thApril, 1955.

From its humble beginning in 1955, the Diesel Shed has evolved to

become the premier shed for diesel-hydraulic locomotives over Indian

Railways.

Showing its commitment towards quality and environmental

management, the Diesel Shed has acquired ISO 9001: 2000 and

ISO 4001:1996 certifications.

This shed has also been entrusted with the maintenance of 140TGottwald Cranes (Break-down Cranes).

This shed is also earning by rendering engineering services to public

sector undertakings having 37 locos since 1979 and carrying out all

major schedules upto periodic overhauling with total satisfaction of

customers.

Total Shed Area = 41141 SQM.Total Covered Area =15417 SQM.Total Staff Employed = 800 approx. Total Capacity for WDS 4 = 108


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Diesel locomotives ::

A locomotiveis a railway vehicle that provides the motive power for a

train. The word originates from the Latin loco- "from a place", Latin

motivus, "causing motion".

A Diesel locomotiveis a type of railroad locomotive in which the prime

mover is a Diesel engine.

Diesel locomotives are classified on the basis of the track Gauge over

which they are designed to run.

1) Broad Gauge2) Meter gauge3) Narrow gaugeAll the diesel locomotive repaired and looked after in ShakurBasti

diesel shed are of Broad gauge type.

These broad gauge locos can also be classified on the basis of

purpose of use.

1)

Passenger Locos2) Goods Locos3) Mixed type Locos4) Shunting Locos or switching locos.


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Passenger Locos : These are ones which are used to carry passengerfrom one place to another

WDP 1 WDP 2 WDP 3 WDP 4

Goods locos : They are used for carrying goods.WDG 2 WDG 3B, WDG 3C, WDG 3D and WDG4

Mixed Locos : They carry both Goods and locos.WDM 1 WDM 2 WDM 2A WDM 2B WDM 3 WDM 3A WDM 3C

WDM 3D WDM 4 WDM 6 WDM 7.

Shunting locos : They are used for shunting purposes.WDS 1 WDS 2 WDS3 WDS4 WDS 4A WDS4B WDS 4C WDS4D WDS 5

WDS 6 WDS 8.

Along with these there are also Diesel Multiple units : DEMU andDHMU

Of All these ShakurBasti loco plant takes care of only :

1)WDM 22)WDS 43)BG DEMU (Broad gauge DEMU)4)MG DEMU (Meter gauge DEMU)


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The classification syntaxes

Locos have classification codes that identify them. This code is of the

form

[gauge] [power] [load] [series]

In this the first item, '[gauge]', is a single letter identifying the gauge the

loco runs on:

W = Broad Gauge Y = Meter Gauge Z = Narrow Gauge (2' 6") N = Narrow Gauge (2')

The second item, '[power]', is one or two letters identifying the power

source:

D = Diesel C = DC traction A = AC traction CA = Dual-power AC/DC traction B = Battery electric(rare)


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The third item, '[load]', is a single letter identifying the kind of load the

loco is normally used for:

M = Mixed Traffic P = Passenger G = Goods S = Shunting L = Light Duty (Light Passenger) U = Multiple Unit (EMU / DEMU)

The fourth item, '[series]', is a digit identifying the model of the loco.

Until recently, this series number was simply assigned chronologically

as new models of locos were introduced.

With this WDM2 corresponds to :

W = Broad Gauge D = Diesel M = Mixed Traffic 2 = This is a series no.On the similar basis we can identify different diesel engines.


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WDM 2 Locomotive

The WDM-2 is the most common diesel locomotive of Indian Railways.

The class WDM-2is Indian Railways' workhorse diesel locomotive. The

first units were imported fully built from the American Locomotive

Company (Alco) in 1962.

Since 1964, it has been manufactured in India by the Diesel Locomotive

Works (DLW), Varanasi.

This is the first Homemade Diesel-electric Locomotive (DEL).

WDM2 is designed for mixed traffic service, passenger and freight. The

loco equipped with fully equalized trimount trucks has medium axle

loading and higher adhesion.

WDM2 has characteristics of low and easy maintenance, reduced noise

and exhaust emissions, fuel saving, safe and comfortable riding andreliable high performance.

Technical specifications :

Builders Alco, DLW

Engine It has an Alco 251-B, 16 cylinders

engine.

With Power Output of 2,600 hp


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It is equipped with Alco 710/720

Turbo supercharger.

1,000 rpm max, 400 rpm idle;

228 mm x 266 mm bore/stroke

compression ratio 12.5:1.

Direct fuel injection, centrifugal pump

cooling system.

Governor This engine uses a Hydraulic

Governor

GE 17MG8 / Woodwards 8574-650

Transmission Electric, with BHEL TG 10931 AZ

generator (1,000 rpm, 770 V,

4,520 amps).

Axle load 18.8 tonnes

Total weight 112.8 t.

Bogies Alco design cast frame trimount

(Co-Co) bogies

Max. Speed 120km/hr

Gear ratio 65 : 18


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At the repair track in front of WDM2

Inside the drivers Cab in WDM 2


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WDS 4 Locomotive

These are basically used for shunting purposes i.e. track shifting from

on track to another.

These are the only IR locos in use today with hydraulic transmission.

Technical specifications :

Engine : These use 6 cylinder MAK engine.

With power output of 700 HP.

Governor: It uses an electric governor.

Transmission : Mak-Suri 2-speed hydromechanical

transmission (WDS-4).

Total weight : 60 tonnes.

Max Speed : 80km/hr


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Starting the WDM 2 Locomotive :

During the visit, with kind co-operation from the Loco shed staff,

students were explained the details about how to start the locomotive.

These can be summarized as ::

The WDM-2 has no key to start the engine - it has a green color switch

in the electrical panel to crank the prime mover. Similarly there is a red

switch to stop the prime mover.

The starting sequence is something like this:

1.First a walk-around of the loco is done ensuring that the locoappears in condition fit for duty. This takes around 10 minutes. All

the fluid levels (coolant, lube oil) are checked at this stage. After

being started, the loco is checked once again before leaving theshed.

2.Close the battery master switch inside the short hoodcompartment.

3.Close the fuel pump breaker and wait for the fuel oil pressuregauge to start showing some reading. The presence of fuel oil

pressure means that the fuel is present at the injectors when the

engine is cranked.

4.Close the crankcase exhauster breaker - this blower removesexplosive vapours from the crankcase during operation.

5.Ensure: loco brakes on, generator field breaker open, reverser inthe neutral position, Engine Control Switch in the Idle position,

throttle in the closed position.


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6.Press the green start switch - the bell will sound inside the enginecompartment warning anyone working there that the beast will

wake up soon. I think it takes a second push of the button during

which the engine is cranked.7.The switch is to be held down till all the cylinders start firing.8.Once the prime mover is running, observe the oil pressure, air

pressure, brake pipe pressure being build up.

9.Observe the battery charging taking place. The battery chargingammeter in the electrical panel always shows a (center) zero

reading - this indicates the charging and discharging of the battery

is perfectly balanced. The charging is checked by operating a

toggle switch near the ammeter - this toggle switches off the fieldto the auxiliary generator (meant for battery charging, etc.) and

the ammeter immediately shows a small negative deflection

indicating a loss of battery charging. Once the switch is closed, the

ammeter swings back to the center zero position.

10. Another check of the loco - some drivers open the crankcaseexhauster breaker at this stage - the positive pressure inside the

crank sometimes shows up oil leaks faster.

11. The throttle is moved to ensure that loco is responding tobeing notched.

12. Release the parking brake, remove any wedges, wheelblocks, or rocks placed at the wheels to stop the loco from rolling.

13. Move the Engine Control Switch from Idle to Run position.14. Observe the signal being pulled off, release the loco brakes

and honk before moving!


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Dieselhydraulic Transmission ::

WDM 2 loco makes use of Diesel hydraulic transmission to convey

power from diesel engines to wheels. On this type of loco, the power is

transmitted to the wheels by a device called Torque Converter. Torque

converter consists of ::

1)Centrifugal PumpIt is the inner rotating part which is mechanically driven by primemover. As it spins, fluid is flung to the outside , a vacuum is created

that draws more fluid in at the center.

2)Turbine WheelIt is the driven wheel,it is on the outer part of the coupling.

3)StatorIt is interposed between the pump and turbine so that it can alter oil

flow returning from the turbine to the pump

As the diesel engine rotates the centrifugal pump, oil is forced

outwards at high pressure. The oil is forced through the blades of the

fixed guide wheel and then through the blades of the turbine wheel,

which causes it to rotate and thus turn the axle and the wheels. The oil

is then pumped around the circuit repeatedly.

The disposition of the guide vanes allows the torque converter to act as

a gearbox with continuously variable ratio. If the output shaft is loaded

to reduce its rotational speed, the torque applied to the shaft increases,


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so the power transmitted by the torque converter remains more or less

constant.

Diesel Electric Transmission ::

In DEL engine prime mover drives an electric generator whoseoutput provides power to the traction motors.

Important components of the Diesel electric propulsion are : Prime Mover Main Generator Traction Motors Control System

In principle, the electrical output from the generator is directed

through the switchgear to the traction motors, which are mechanically

coupled to the drivers by spur gearing.

Throttle Control :

Locomotive power output, and speed, is typically controlled by the

engineer (driver) using a stepped or "notched" throttle that produces

binary-like electrical signals corresponding to throttle position. This

basic design lends itself well to multiple unit (MU) operation byproducing discrete conditions that assure that all units in a consist

respond in the same way to throttle position.

The throttle mechanism is ratcheted so that it is not possible to

advance more than one power position at a time. The engineer could


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not, for example, pull the throttle from notch 2 to notch 4 without

stopping at notch 3. This feature was intended to prevent rough train

handling due to abrupt power increases caused by rapid throttle

motion .

When the throttle is in the idle position, the prime mover will be

receiving minimal fuel, causing it to idle at low RPM. Also, the traction

motors will not be connected to the main generator (MG) and the

generator's field windings will not be excited (energized)the

generator will not produce electricity with no excitation. Therefore, the

locomotive will be in "neutral

To set the locomotive in motion, the reverser handle is placed into the

correct position (forward or reverse), the brakes are released and the

throttle is moved to the run 1 position (the first power notch)

Placing the throttle into the first power position will cause the traction

motors to be connected to the MG and the latter's field coils to beexcited. It will not, however, increase prime mover RPM. With

excitation applied, the MG will deliver electricity to the traction motors,

resulting in motion. If the locomotive is running "light" (that is, not

coupled to a train) and is not on an ascending grade it will easily

accelerate. On the other hand, if a long train is being started, the

locomotive may stall as soon as some of the slack has been taken up, as

the drag imposed by the train will exceed the tractive force being

developed.

As the throttle is moved to higher power notches, the fuel rate to the

prime mover will increase, resulting in a corresponding increase in RPM

and horsepower output. At the same time, MG field excitation will be

proportionally increased to absorb the higher horsepower. This will


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translate into increased electrical output to the traction motors, with a

corresponding increase in tractive force. Eventually, depending on the

requirements of the train's schedule, the engineer (driver) will have

moved the throttle to the position of maximum power and willmaintain it there until the train has accelerated to the desired speed.

Main Alternator

The diesel engine drives the main alternator which provides the power

to move the train. The alternator generates AC electricity which is used

to provide power for the traction motors mounted on the bogies. In

older locomotives, the alternator was a DC machine, called a

generator. It produced direct current which was used to provide power

for DC traction motors. Many of these machines are still in regular

use. The next development was the replacement of the generator by

the alternator but still using DC traction motors. The AC output is

rectified to give the DC required for the motors.

Motor Blower

The diesel engine also drives a motor blower. As its name suggests, the

motor blower provides air which is blown over the traction motors to

keep them cool during periods of heavy work. The blower is mounted

inside the locomotive body but the motors are on the trucks, so the

blower output is connected to each of the motors through flexible

ducting. The blower output also cools the alternators. Some designs

have separate blowers for the group of motors on each truck and


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others for the alternators. Whatever the arrangement, a modern

locomotive has a complex air management system which monitors the

temperature of the various rotating machines in the locomotive and

adjusts the flow of air accordingly.

Compressed Air System

Each Diesel engine drives a direct-connected, two-stage, air compressor

which takes air from the atmosphere and delivers it under pressure to

the main reservoir, where the air is stored and cooled and in which the

moisture contained in the air is condensed into water from where it can

be readily drained before it enters the various operating parts of the air

system. Air from the main reservoirs is piped to the air brake system,

the air control system, and to the other air-operated devices used

throughout the locomotive.The main reservoir air is connected

between units by flexible hose.

Batteries

The diesel engine needs a battery to start it and to provide electrical

power for lights and controls when the engine is switched off and thealternator is not running.Battery powered vehicles have benefits that

include low noise, small vibrations,simplified transmission systems, and

reduced pollution when compared to combustion engines.The battery

is charged from the auxiliary generator or generators on the unit, and

the charging voltage is controlled by a voltage regulator to maintain a


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constant voltage of approximately 74 volts.The battery is used for lights

in the operating cab and engine room and provides power to the

control and indication circuits of the locomotive.

Lubrication

Like an automobile engine, a diesel engine needs lubrication. In an

arrangement similar to the engine cooling system, lubricating oil is

distributed around the engine to the cylinders, crankshaft and other

moving parts. There is a reservoir of oil, usually carried in the sump,

which has to be kept topped up, and a pump to keep the oil circulating

evenly around the engine. The oil gets heated by its passage around

the engine and has to be kept cool, so it is passed through a radiator

during its journey. The radiator is sometimes designed as a heat

exchanger, where the oil passes through pipes encased in a water tank

which is connected to the engine cooling system.

The oil has to be filtered to remove impurities and it has to be

monitored for low pressure. If oil pressure falls to a level which could

cause the engine to seize up, a "low oil pressure switch" will shut down

the engine. There is also a high pressure relief valve, to drain off excess

oil back to the sump.


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Dynamic Braking:

Dynamic braking takes advantage of the fact that the traction motor

armatures are always rotating when the locomotive is in motion and

that a motor can be made to act as a generator by separately exciting

the field winding. When dynamic braking is utilized, the traction control

circuits are configured as follows:

The field winding of each traction motor is connected across themain generator (MG).

The armature of each traction motor is connected across a forced-air cooled resistance grid (the dynamic braking grid) in the roof of

the locomotive's hood.

The prime mover RPM is increased and the MG field is excited,causing a corresponding excitation of the traction motor fields.

The aggregate effect of the above is to cause each traction motor to

generate electric power and dissipate it as heat in the dynamic braking

grid. Forced air-cooling is provided by a fan that is connected across the

grid. Consequently, the fan is powered by the output of the traction

motors and will tend to run faster and produce more airflow as more

energy is applied to the grid.

Ultimately, the source of the energy dissipated in the dynamic brakinggrid is the motion of the locomotive as imparted to the traction motor

armatures. Therefore, the traction motors impose drag and the

locomotive acts as a brake.


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Air Brakes :

An air brakeis a conveyance braking system applied by means of

compressed air.

In the air brake's simplest form, called the straight air system,

compressed air pushes on a piston in a cylinder. The piston is

connected through mechanical linkage to brake shoes that can rub on

the train wheels, using the resulting friction to slow the train. The

mechanical linkage can become quite elaborate, as it evenly distributesforce from one pressurized air cylinder to 8 or 12 wheels.

The pressurized air comes from an air compressor in the locomotive

and is sent from car to car by a train linemade up of pipes beneath

each car and hoses between cars.

Modern air brake systems are in effect two braking systems combined:

The service brake system, which applies and releases the brakes

during normal operations, and

The emergency brake system, which applies the brakes rapidly in the

event of a brake pipe failure or an emergency application by the

engineer.


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Purpose of Diesel Shed ::

The Shakurbasti diesel shed was constructed for repair and

maintenance of diesel locos.

They follow a strict plan for maintenance of the locos. Every loco has a

specific time after which it has return to the Shed for testing and other

repairs.

Diesel Shed also include a Workshop in which different components of

loco are machined or repaired

The basic things they inspect upon are :

1)Fuel Tanks2)Wheels and Axles3)Brake System4)Trucks5)Wheels and Axles6)Speed Indicators7)Different Level Switches8)Audible Signals9)Illuminating Devices10) Basic Engine components11) Turbocharger12) Radiators13) Filters14) Batteries15) Cab etc.


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Basically 4 Non destructive tests are employed in the Diesel Shed.

1)In ultrasonic testing, very short ultrasonic pulse-waves withcenter frequencies ranging from 0.1-15 MHz and occasionally up

to 50 MHz are launched into materials to detect internal flaws or

to characterize materials.

2)Magnetic flux leakage (MFL)is a magnetic method ofnondestructive testing that is used to detect corrosion and pitting

in steel structures, most commonly pipelines and storage tanks.

The basic principle is that a powerful magnet is used to magnetize

the steel. At areas where there is corrosion or missing metal, the

magnetic field "leaks" from the steel.

3)Liquid penetrant inspection(LPI), is a widely applied and low-costinspection method used to locate surface-breaking defects in allnon-porous materials (metals, plastics, or ceramics). Penetrant

may be applied to all non-ferrous materials, but for inspection of

ferrous components magnetic-particle inspection is preferred for

its subsurface detection capability. LPI is used to detect casting

and forging defects, cracks, and leaks in new products, and fatigue

cracks on in-service components.

When used with a Red die it is known as Red Die Penetrant

Inspection. Reddye penetrants are visible under normal light.


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4)Zyglo Fluorescent Penetrant TestThe ZYGLO fluorescentPenetrant process is a nondestructive testing (NDT) method that

helps you locate and identify surface defects in order to screen

out potential failure-producing defects, correct production

problems and increase product uniformity. It is a quick and

accurate process for locating surface flaws such as shrinkage

cracks, porosity, cold shuts, fatigue cracks, grinding cracks, heat

treat cracks, seams, forging laps, forging bursts, through leaks,

and lack of bond.

Steps involved in Zyglo test are as follows :

STEP 1PRE-CLEAN PARTS

STEP 2APPLY PENETRANT

STEP 3REMOVE PENETRANT

STEP 4DRY PARTS

STEP 5APPLY DEVELOPER

STEP 6INSPECTION

shakurbasti diesel shed report new

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