CHITTARANJAN LOCOMOTIVE WORKS

Model Railway Society is a cohesive body made up of some 25 men coming together from various

parts of Pune. Having diverse professions, they share an intense love for Indian railways. The Society

is now 25 years old and has paid visits to several important railway locations in the past.

Chittaranjan Locomotive Works had been their savored dream for a long time. A Sixteen- member-

team communicated with the Chief PRO at CLW, who managed a semiofficial visit for the members.

The team reached Chittaranjan on the morning of 22nd July 2013 and stayed overnight to continue

the visit on the following day. This article stems from the actual information given by the technical

staff on site and also from some formal publications, furnished by the PRO of the CLW. Every effort is

made to maintain accuracy in the technical information. We hope this short account should help a

railway enthusiast to obtain an overview of what Chittaranjan Locomotive Works today stands for.

History of CLW : Before Independence, nearly 42 private railway companies owned the railways of

India and they had their own ways of procuring the locomotive power and all were imported for a

long time. After the great World wars, these companies found it difficult to procure locomotives

from overseas and a unified need was felt to have these locomotives built indigenously. However it

was only after independence that the unified effort to build a locomotive plant was realized.

Chittaranjan Locomotive Works had a very modest beginning, when the tiny Santhal village in west

Bengal was identified as a place to establish a locomotive factory. The closest railway station to this

area was Mihijam on the Asansol Patna section. This indigenous Locomotive plant was named

“Chittaranjan” to pay tribute to the great Deshbandhu Chittaranjan Das. (There is a legend that the

land formerly belonged to the Chittaranjan family after whom the plant was named). Even the

Mihijam railway station was later christened “Chittaranjan”.

Tata had established TELCO in 1945, which built the some Meter gauge steam locomotives for

Indian railways, but they soon found difficult to cope with the growing demands of the fast

expanding railway industry in India. CLW as it is now called (CHIREKA in Hindi), was thus established

in February 1948 by the Government of India and the first freight Steam locomotive, WG was rolled

out in November 1950. The production soon expanded to build WP’s, WT’s and WL’s. It also built

YG’s for Meter Gauge traffic in India. CLW built a total number of 2351 Steam locomotives for Indian

Railways.

Although the CLW are now renowned for building Electric Locomotives alone, the factory built a

large number of Diesel Locomotives for Indian Railways from 1968 to 1994. They mainly built Diesel

Hydraulic Locomotives including WDS4, WDS8, YDM2 and a number of locos for the narrow gauge

railways. Today the CLW stands proud not only in manufacturing the conventional electric

locomotives with DC traction Motors, but it also builds microprocessor controlled modern mainline

Electric Locomotives using three Phase AC induction Motors. With a modest beginning by building 5

electric Locos in 1961, CLW has increased its tally to 250 locos in the year 2012, taking the total to

4646 Electric Locomotives to date.

Our Tour : Model Railway Society, Pune has about 25 members. Sixteen of them had volunteered to join

the trip to Chittaranjan. 14 of them took the Duronto on 20th July to reach Howrah on 21st evening. Me

and Pande flew to Kolkata and joined the group on Howrah station on the 22nd morning to board the

Poorva Express at 08 00 hrs. Poorva was swift enough to take us to Chittaranjan at 11 sharp.

Chittaranjan Station is a beautiful tiny station and is surprisingly clean. Believe or not, but the CLW

officials had arranged a minibus to collect us and take us to the Guest House. After a quick wash we

went and met the Chief PRO Mr. Mantar Singh. He is a very warm and receptive character and was truly

pleased to see a team of 16 people travelling all the way from Pune only to visit CLW. He gave us a plan

of the tour and later directed us to the main assembly shop.

This was a rapid tour which showed us the building of Electric Traction Motors (Both DC and 3 phase AC)

and their alignment over the bearings of the axles. The most exciting part was the alignment of the Spur

gears between the motors and the axles. We saw machining and grinding of the axle rods and the

wheels to ultimate precision. The winding of the stators was a treat to see. Body shells of the

locomotives are either casted as whole or fabricated, depending on the model protptype. The

magnitude of the work and the dimension of the hardware is simply mindboggling.

Later we visited the machining shop, where we saw the axle turning, wheel machining and assembly of

the wheel sets. Modern locomotives use fabricated bogies. Complete machining and fabrication of the

bogies is performed comprehensively in this shop.

On the morning of the second day they took us to visit a small loco museum, named Deshbandhu Loco

Park. A number of famous CLW products were on display, notably the last WG (wrongly named Antim

Sitara, since the real Antim Sitara was a YG). We also saw some live steam models, which are currently

out of function. A 1/4th gauge garden railway exists on the premises, but works only on special

occasions.

Later on that day we visited the “Testing and Quality” lab. The most impressive item was the “Foundry

Master”, a German equipment, which analyses a metal and gives us the constituents (or impurities)

literally in a flash. We also saw various other equipment, which tested and estimated the tensile and

compressive strengths of the metals again in a very short time. Somehow the enthusiasm of the staff

rather exceeded ours and this session turned out to stretch our patience a bit.

The best part of our trip was yet to arrive. We had asked to see a qualified Electrical Engineer to answer

some of our questions. Mr. Mantar Singh arranged a meeting of ours with Mr. Sahu, who was a true

genius. Just as our session began getting interesting, a person of Managerial level walked in and rudely

interrupted our session. He said he wanted to start an important meeting. Anyhow the session with Mr.

Sahu was thoroughly absorbing.

Steel Foundry

The Steel Foundry is an impressive plant, located about a km. away from the workshop. Established in

1963, in collaboration with M/s. F. H. Lloyd of UK in 1963, the foundry now is virtually self sufficient and

casts Bogie Frames, axle rods, axle box houses and suspension tubes. It also casts a number of items for

Traction Motors such as Rotor Clamps and Bearing Brackets. They are now cast in light weight steel and

are transported to the Machine Shop for machining, turning, finishing and final assembly.

In the heart of the forging furnace, the temperature of the molten metal is raised to 1620 degree Celsius

by an electrical current of 60 kilo amperes at 12 kV to produce a powerful arc. We saw the burning

furnace which made a frightening and crackling sound. However we were not able to see the actual

casting, since this is performed only at certain times of the day. The temperature later drops to 1580

degrees while the metal is poured into the moulds. All in all this was a thumping experience.

As we approached the end of our visit, Mr. Mantar Singh invited us all in his office and presented each

one of us a CLW calendar and a Brochure. We had a wonderful experience all-round. As we bid good bye

to the CLW, we all had a proud feeling about CLW. After a thoroughly informative experience, we drove

back to Asansol Railway Station to board the 12321 Up to catch our way back.

While we returned by Howrah Mumbai Express, everyone of us carried a proud sentiment within us.

What a great experience it was for two full days. No surprise really that the Electrical energy, when

harnessed and controlled by electronics, can do wonders in this world.

Some of my jottings about the CLW, which I would love to share with my Railfan Colleagues.

Electric Power Supply : CLW draws its power supply from Damodar Valley Corporation (DMC) situated at

Maithan, a small town 15 kms away from Chittaranjan. DMC hosts a Hydroelectric plant of 40 MW and a

Gas Turbine Unit of 90 MW connected to the main grid. Chittaranjan also has an in-house generating

capacity of 11.6 MW as a backup facility.

The Conventional Electric Locomotives : Conventionally the electrical circuit is completed through the

body of the loco and earthed via the rails. 25 kV single phase AC supply is drawn by the pantographs

and is fed to the transformers. This is further rectified to 750 V DC and supplied to the traction motors

through a tap changer (essentially through a series of resistances). DC Traction motors were believed to

have a higher initial torque and were universally used in most situations including all the diesel electric

locomotives.

The Technology of Modern Locomotives (as I understood) : The Pantograph receives the fixed

frequency (50 Hz) alternating current of 25 kV from the overhead equipment (OHE). This is filtered

through Protection Circuits to remove impurities in frequency. It is subsequently fed to a Transformer

for stepping down. There are four secondary coils. The output from secondary coils is distributed as

follows.

Coil 1. Fed to Gate Turnoff Circuit (GTO), which converts the output to DC and later chopped to

three phase AC, supplying variable frequency and variable voltage to the Traction Motors. This

technology is now getting upgraded to IGBT (Insulated Gate Bipolar Transistor)

Coil 2. Main Compressor Motors. These are simple AC induction Motors

Coil 3. Blower Motors (AC). There are at least three sets of these.

Coil 4. Supplies accessory equipment of the Locomotive.

Conventional AC Motors are simple induction motors , where the stator receives electrical current

though radially arranged field coils. The electromagnetic induction thus produced, moves the Rotor in

the direction opposite of the poles. The speed of rotor depends directly on the frequency of current and

the number of poles. (e.g. n = Frequency *120 / no. of Poles). Thus their speed synchronises with the

frequency and are therefore called Synchronous Motors. These motors have a fixed speed and fixed

torque, which makes them unsuitable as traction motors, where the demands of torque and speed are

variable.

Three Phase Asynchronous Motors : The three phase technology owes its roots to Bobardier

Transportation Switzerland. The Stator in these motors is supplied with phases at three different points

distributed at 120 degrees angle with each other. The induction thus produced has a motive power at

three points in a cycle. The resultant speed and torque of the rotor depends on the frequency and the

voltage of the induced field. A microprocessor modulates the frequency, phase and the voltage to

generate the required torque and speed. As I understood the voltage varies between 1 and 2180 V AC

and the frequency varies between 40 and 65 Hz. CLW commenced building of 850 kW and 1150 kW 3-

phase traction motors in 1998 and started rolling out modern electric Locomotives in 1999.

Traction Motors: This basic motive force is the soul of CLW. It now builds Type 15250A DC series

motor which works on 750 V DC and produces 630 kW of power. These are used for conventional 5000

BHP 25 kV locomotives such as WAP 4 and WAG 7. This technology has now given way to the modern 3

phase AC asynchronous traction motors. CLW thus is now engaged in building two important types of 3

phase motors, the 850 kW 6FRA 6068 and the 1150 kW 6FXA 7059 for use in WAP 7, WAP 5 and WAG 9.

Current CLW products can be tabulated in the following form

Type Power Output

No. of

Axles

Axle Load

Traction Motors Purpose Speed

potential Technology Bogies Highlights

WAP-4

5000 BHP

6 18.8

Tonnes Conventional DC

Fast passenger

140 kmph

Tap Changer Flex-coil

Cast Steel

Hauls Mainline Superfast Trains

including Rajdhani Expresses

WAG-7

5000 BHP

6 19.5

Tonnes Conventional DC

Heavy Freight

100 kmph

Tap Changer

Fabricated High

Adhesion

Hauls Air Braked Heavy Freight Stock

WAP-5

5400 BHP

4 20.8

Tonnes Three Phase AC Asynchronous

Superfast passenger

160 kmph

Microprocessor (GTO)

Controlled variable

Frequency variable Voltage

Two Axles per Bogie

Disk Brakes

Originally ABB transferred Technology.

Useful Regenerative Potential

WAP-7

6000 BHP

6 20.5

Tonnes Three Phase AC Asynchronous

Long Fast Passenger

Trains

160 kmph

Microprocessor (GTO)

Controlled variable

Frequency variable Voltage

The only Loco with Head-on Generation capability eliminating the need for End-on

Generator car

WAG-9

6000 BHP

6 20.5

Tonnes Three Phase AC Asynchronous

Heavy Duty Air Braked

Freight traffic

100 kmph

Microprocessor (GTO)

Controlled variable

Frequency variable Voltage

Loco has Air Conditioned Driver's

Cab

WAG-9H

5000 BHP

6 20.5

Tonnes? Three Phase AC Asynchronous

Heavy Duty Air Braked

Freight traffic

100 kmph

Microprocessor (GTO)

Controlled variable

Frequency variable Voltage

High Adhesion

Increased Axle load to improve the wheel

Adhesion. Suitable for long and heavy Freight

Rakes

WAG-9i

5000 BHP

6 20.5

Tonnes? Three Phase AC Asynchronous

Heavy Duty Air Braked

Freight traffic

100 kmph

GTO replaced by IGBT based

Propulsion System

Improved performance and reliability, better

control and regeneration, reduced losses. Modular Design

Some Photos taken during our visit

1. Antim Sitara” show cased in the form of a WG

2. Photograph of the old Santhia village, where the plant was established

3. The majestic building of the Asansol Junction Railway Station

4. Entrance to the “Deshbandhu Loco Park”

5. The Furnace of the Steel Plant

6. Sun setting over the Chittaranjan Township

7. The expanse of the Steel Foundry

8. The freshly rolled out WAG 9H and WAP 4

9. The Gang that visited CLW in July 2013

Steam Locomotives built by CLW so far

WG (1908), WP (259), WT (30)

WL (94), YG (60)

Total Steam Locos = 2351

Diesel Locomotives built by CLW so far

WDS-4,WDS-8, YDM-2

NDM-5, ZDM-3, ZDM-4A, ZDM-5

Electric Locomotives built by CLW so far

WCG-2, WCM-5

WAG-1, WAM-4, WAG-7

WAP-1, WAP-3, WAP-4,

WAP-5, WAP-7

WAG-9, WAG-9H, WAG-9i

Downside of the CLW

It is painful to write these lines after having such an exciting tour. However while we visited the place,

we found the following aspects rather disturbing.

1. The machine shops appeared rather baron and looked as if nothing much is going on there.

There is too much of space which is baron and unutilised.

2. We all felt a lot of more work could have been done in the plant, particularly when we saw a lot

of machinery lying idle. The number of workers who really worked appeared very scarce.

3. It was a pity to see a number of items procured by outsourcing, especially the fabricated body

shells of locomotives. The fabrication unit inside the plant looked quite capable of doing the job.

4. It was rather hard to find persons, who were truly qualified to answer the technical queries

raised by our members.

This aside, we had a memorable experience all round. CLW is not only a heavy industrial plant ; it’s also a

proud symbol of a distinguished and enviable venture of the Independent India.

Acknowledgements : We are extremely indebted to the PRO of CLW, Mr. Mantar Singh, who was

committed to make this visit a reality. We all owe a lot to our Secretary Mr. Amod Gune, who took

immense efforts to make this happen. I am also indebted to our member Mr. Jayant Kelkar, who

virtually educated me in the science of Electrical Engineering during the entire course of our visit.

Shirish D. Yande

5 August 2013