EVOLUTION OF COACH BUILDING AT ICF

INTRODUCTION:

M/s Car and Elevator Manufacturing Corporation Ltd., Schlieren-Zurich (Switzerland) were invited by Indian Railways for collaboration in connection with the manufacture of all-steel, light-weight passenger coaches of modern design in India. An agreement between the Government of India and M/s Car and Elevator Manufacturing Corporation Ltd., was signed on the 28th May 1949. A supplemental agreement was concluded on the 27th June 1953.

By the end of July 1951 an appropriate layout for the coach building factory with the prescribed capacity of 300 unfurnished coach shells a year had been worked out and submitted to the Board. Later the expected maximum yearly production output was fixed at 350 unfurnished coach body shells with pertaining bogies. Decision had also been taken that the production start should fall within the second half of 1955. The production of 350 coach shells with the respective bogies a year i.e., one unit for every six working hours was the initially set target of the ICF.

The evolution of Light-Weight Coach : Design and manufacture

In the past it was generally accepted that heavy vehicles possessed better riding qualities than light ones. Experience has however, shown that intelligent design leads to improved efficiency in operation. Old-fashioned considerations based on static design do not meet the requirement of modern design. Lightweight design and improved efficiencies are synonymous. If greater effectiveness is required, a reduction in weight is essential. The improved effectiveness becomes economically effective in a number of ways, in increased capacity, in reduced operation expenses, in improved service and life. By taking these principles into consideration, we succeeded to reduce the weight of our passenger coach from 42.5 tons to 35.5 tons. Table below shows how this weight reduction was achieved.

Stressed skin carriages possess very favourable static and dynamic qualities. This applies particularly to the resistance against torsional and bending stresses, which is considerably better than that of heavy standard carriages. The vehicle possesses extraordinary high compression rigidity, particularly over the entire length of the passenger compartments. The end portions i.e., lavatories possess lower compression rigidity and thus in case of accidents these parts would be destroyed first and thus absorb the collision energy.

Hollow girders are far superior to solid girders so far as the utilisation of material is concerned. Although hollow girders have been known for some time, it was not originally possible to utilise them to the extent now made possible by the use of stressed skin construction. The hollow girder possesses a high moment of resistance and a high working capacity both in torsion and bending. It is thus eminently suitable for being dynamically stressed in every direction. It is at its best when uniformly thin girder walls are employed. The reduction in weight of the lightweight coaches has been achieved by making full use of the stressed skin construction and by the use of light alloy fittings, etc. The underframe, side walls and roof are united into what might be termed as a static tube representing the thin wall hollow girder consisting of steel sheets. Since thin are capable of dealing with compression and shearing stresses only to a very limited extent, the resistance must be increased. This has been achieved by the provision of suitable pressed grooves or welded ribs. Corrugated sheets, carlines are utilised for the underframe and roof respectively and these deal to a large extent with the buffing stresses. The sidewall pillars together with the carlines and underframe cross menbers, form frames which ensure the necessary rigidity to the structure. The end walls are made of steel sheets. These, together with the sidewalls, floor and roof form a compression and bending resistant tube. The lavatory and the vestibules are less rigid than the central passenger-carrying part of the vehicle. The above principles have been applied rigidly to the coach being manufactured at Integral Coach Factory. This was the design of the coach when the production started at ICF during 1955.

Establishment of Furnishing Division:

The production was inaugurated on 2nd Octorer 1955 and initially ICF manufactured only 12 coaches in the first year. As mentioned earlier, furnishing of coaches was carried out by the zonal Railway workshops. Categorised as conventional coaches, the first few years at ICF was totally dedicated to the production of conventional shells. All these were broad gauge shells only. Later during the year 1958, ICF started furnishing of coaches also in the shell division itself.

During the year 1962, a separate furnishing division was set up and the production was inaugurated on 2nd October 1962. There after full-fledged furnishing was carried out in ICF itself.

Modifications in the underframe:

The trough floor of the underframe was positioned at the centre of the underframe with cross bearers above and below it. Magnesium Oxy Chloride was used for the construction of flooring. Later developments modified the underframe by keeping the trough floor to the sole bar level and thus the 'raised trough floor design' was evolved. This has made the furnishing work easy and simple and the heavy Magnesium Oxy Chloride used for flooring was totally eliminated and the coach weight was considerably reduced. Plywood/Compreg has been used since then for the flooring arrangement with PVC Sheeting over it. Lot of study has been made to improve the corrosion resistance of the components especially the Underframe. Of late, Corten Steel has been the material for majority of the coach components upto 6mm thickness irrespective of the location. Recent developments in the design have replaced the Trough floor material with austenitic stainless steel material to eliminate trough floor corrosion.

Modifications in the Side Wall:

The four-door design has been modified to three-door design for Second Class coaches, that has increased the seating capacity from 80 to 90. This design has shifted the lavatories to the ends of the coach thus making way to keep the passenger area cleaner and tidy. However, the sleeper coaches have only two doors per sidewall. In the recent developments, the body pillars are being manufactured with austenitic stainless steel material instead of conventional corten steel.

Modifications in End Wall:

There were no much modifications in the end wall design except that the provision for the vestibule arrangement. The recent development is that the box type end stanchions have been replaced with the 'I' section girders. This has also resulted in coach weight reduction without compromising the safety aspects for which the end stanchions have been provided.

Modifications in the Roof:

The roof is probably the only major component of the coach that has not undergone much change. Internal fittings however will be changing according to the individual coach design. However, on the standardisation part, the fan brackets, berth suspension brackets and the lamp brackets have been standardised and brought to minimum number of designs. For e.g., there were about 108 different designs of fan brackets, which became only of 4 to 5 designs after standardisation.

Design features of earlier bogie and modifications taken place thereafter:
The initial bogie was made with coil springs in the primary suspension and leaf springs in the secondary suspension. The quality of leaf spring manufacture had to be to the highest possible accuracy to avoid any failure of these springs. With a view to providing better riding comfort and reducing the unsprung mass, the leaf springs in the secondary suspensions were later replaced with coil springs. Thus the ICF bogie design has become 'All coil Bogie.' Motor coaches have been provided with nested spring to match with the coach weight. As a further improvement to the riding comfort, air spring bogies have been developed and are put in to service, mainly for the EMU and DMU Coaches.

CONVENTIONAL COACHES:

Beginning with third class coaches ICF slowly added to its conventional category many other types of coaches. These include First Class, First and Second Class, First-Second and third class coaches, Third class sleeper coaches, Second class sleeper coaches, pantry cars, day coaches, kitchen cars, luggage racks and so on.

Later, ICF has also started manufacturing Metre Gauge coaches with all the above types of coaches. The first MG coach was turned out during 1963-64.

First class coaches, first and second class coaches:

These are Luxury coaches with limited accommodation and comfort. One coach consists of accommodation for about 18 passengers. In case of First and Second class coaches (FS), half the portion of the coach consists of first class furnishing and the remaining portion is made as second class sleeper coach.

Third class coaches and Day coaches:

These are of simple design with wooden seats with a seating capacity upto 90 passengers per coach. Initially there were 4 doors aside and later the four door sidewalls were also replaced with three doors aside in the subsequent designs. The day coaches are only for day travel and provision for berth is not given. The latest day coach has got a seating capacity for 108 passengers.

Pantry cars and kitchen cars:

These are manufactured with a view to provide food and snacks to the passengers during the long distance travels. Hence these coaches are particularly attached to the long distance trains.

Third class and Second class sleeper coaches:

Initially two types of sleeper coaches were designed and manufactured viz., two-tier sleeper and three tier sleeper coaches, the latter having more number of berths.

Second Class Luggage and brake van:

These coaches are to carry huge volume of luggage for long distances with ease and at less cost. Provision for guard is also made in these coaches and these are attached at the end of the formation.

During the year 1974-75, the concept of third class was eliminated and now only Second Class exists. The conventional category caters to the travelling needs with comfort for majority of the population in the country. Nearly 70% of ICF's total production as on date belongs to this category and now also, over 50% of the capacity is being utilized annually to produce these coaches, because of the unending demand from the user railways.

SELF PROPELLED COACHES:

During the year 1962-63, ICF had diversified its manufacturing capabilities with the introduction of self-propelled coaches. These are the coaches that are most commonly used for sub-urban transport in majority of the cities throughout India.

As the name implies, these trains do not require a separate engine to haul the formation. Each formation contains a minimum of two motor coaches and other trailer coaches as per the formation requirements. Further there are some other categories but the popular category being the Electrical Multiple Units (EMUs). Other categories include DEMUs, MEMUs and Metro Coaches.

Electric Multiple Units (EMUs):

These are the best-suited passenger coaches for sub-urban transit. The coaches are wide enough to carry maximum number of passengers with comfort and speed. These coaches are capable of travelling at an average speed of 40-50 km/h between stations. The formation consists of motor coaches and trailer coaches. To accommodate seating for more passengers, the body of these coaches was made wider than conventional coaches. Thus these coaches are also called as wide-bodied coaches.

The initial manufacture of this category of coaches was only to run on AC supply. The first coach was turned out during the year 1962-63 and it was a trailer coach. The very next year ICF manufactured the motor coach to make a formation of the EMU.

There are three categories in this viz., Motor Coach, Trailer coach and trailer coach with provision for vendor compartment. These coaches are respectively called as AC EMU B, AC EMU C and AC EMU D coaches. During the initial stages of manufacture 'A' type coaches were also made but later the 'A' type and 'D' type were merged and only D trailers were made.

After a gap of six years, during 1968-69, the first DC EMU coach was manufactured and as the name implies, this was intended to run on DC supply. These coaches are made to run in Bombay sub-urban services. These coaches also have the same categories as that of AC EMUs.

As a further development in the category of self-propelled EMU coaches, ICF during the millennium has manufactured coaches that can run on dual voltage system. Thus, the AC DC EMUs are the latest additions in this gallery. The main aim of these coaches is to keep the railway services uninterrupted during the transition period in the Mumbai sub-urban services from DC voltage system to AC Voltage system. Separate traction packages are provided for these coaches to run on AC and DC voltage supplies in different areas depending on the availability of power supply. The first coach in this category was manufactured during 2000-01.

Diesel Electric Multiple Units (DEMUs):

During the year 1993-94 the 700 HP DMUs were introduced into the Indian Railway sub-urban system. These are meant for such sub-urban services where the overhead supply is not laid. One unit consists of One driving power car, one trailer car and one driving trailer car. The passenger carrying capacity is over 750 per unit. The train formation may contain two to four such units, depending on the operational requirements. Thus, these coaches are equally good in service as EMUs.

The recent improvement in these coaches is the High Horse Power DEMUs with a hauling capacity of 1400 HP instead of 700 HP. This was developed during the year 1999-2000. This enables to make the formation of one power car and three trailer cars per unit with a total carrying capacity of 1092 passengers.

Mainline Electric Multiple Units (MEMUs):

These are also introduced during the same year along with DMUs. These coaches are used for short and medium distance commuter traffic. The development of these coaches is due to the moving dimension restrictions of wide bodied EMUs on the electrified trunk routes where regular long distance passenger and goods trains pass through and the low level platforms of the way side stations. The MEMU has the operational features of fast acceleration and deceleration, Electro-pneumatic braking system and Schaku coupler which make the train functionally more like a sub-urban EMU, maintaining the average speeds to match the fast mail or express trains so that it does not slow down the system. These coaches are capable of running at a maximum speed of 105 km/h. The entire formation (two units of 4 coaches each) is capable of carrying as many as 2436 passengers.

Metro Coaches:

ICF has specifically designed, manufactured and supplied these coaches for the Kolkata Metro Underground Railway System. The special features incorporated are:
a. Traction power supply through third rail current collection system.
b. Automatic door opening / closing and continuous monitoring of the transit.
c. Automatic train protection feature which will automatically apply the brakes in case of human failure.
d. There is also automatic operation of the train with the driver exercising a supervisory function.
e. A public address system is provided on the trains to announce approaching stations. A central controller can contact any of the train crew and also make important announcements directly to passengers over the system.

With all these sophistication built in, the design and manufacture of these coaches to a very high standard of reliability and safety has been a major task. This was achieved without any technical collaboration. The entire formation is capable of carrying 2356 passengers.

AIR-CONDITIONED COACHES:

The air-conditioned coaches have been the prestigious coaches manufactured at ICF. The first AC coach was rolled out during the year 1966-67 wherein three types of coaches in this category were manufactured. There are many types of coaches in this group viz., two-tier sleeper coaches, first class coaches, composite coaches, pantry cars, chair cars, executive chair cars and so on. Special rakes were also manufactured to run prestigious trains like Rajadhani and Shatabdi expresses, which are fully air-conditioned formations. The AC composite coaches consist of two-tier AC portion and First Class AC portions.

Some special coaches like Palace on Wheels, were also manufactured to cater the needs of the tourism corporations. These are fully air-conditioned coaches. The Palace on Wheels is a masterpiece in the history of ICF. During 1991-92 specially designed and manufactured for the Rajasthan Tourism Development Corporation, these coaches were furnished in the style of ancient architecture that can be seen only in the Rajasthani palaces. These coaches were of Metre Gauge. Later during the year 1995-96, similar Palace on Wheels was manufactured for broad gauge.

Initially Underslung AC equipment was used. Later it has been modified and roof-mounted AC coaches came into existence.

EXPORT PERFORMANCE:

The 'Export Era' of ICF had commenced during the year 1967-68 with just two bogies supplied to Thailand. The first export order of coach was accomplished during the year 1971-72 with 113 coaches exported to Taiwan against a stiff international competition. As a proof of satisfied quality requirements, ICF has got repeated orders from various countries, thus ICF so far manufactured and supplied 425 coaches and 359 bogies and many spares to 11 Afro-Asian countries. These include conventional coaches and air-conditioned coaches depending on the requirement of the respective countries with respect to the track gauge and other features under their contract. Every export order was unique with respect to the requirements and amenities provided in the coaches. It has been a different experience to provide special features like air operated sliding doors, reversible seats, air brakes, special metallic vestibules for safe passage, air conditioning etc.

SPECIAL COACHES:

Special coaches include those, which are used only for special and specific purposes. These coaches include Diesel Electric Tower Cars (DETC), Accident Relief Medical Vans (ARMV), Inspection Cars (RA), Fuel Test Cars, Track Recording Cars, power cars both AC and non-AC and so on.

DIESEL ELECTRIC TOWER CARS (DETC):

This is highly useful for the overhead equipment inspection and repair. It has an electronic load control module for optimum operational efficiency. The vehicle is provided with dual brake system and can operate at a speed of 100 kmph. It has a compact workshop with all facilities to attend on-site maintenance and break-down, an electronic telephone exchange for inter-communication between various workstations and adequate rest and toilet facilities for the crew.

ACCIDENT RELIEF MEDICAL VAN AND TOOL VAN (ARMV AND ARTV):

These self-propelled coach-sets consist of one Power Car cum Tool Van and one air-conditioned Medical Van. The power car supplies the required power for traction as well as all other electrical appliances. The medical van houses a fully equipped operation theatre with surgical and life-sustaining equipment and a ward with 12 beds. These Accident Relief Medical Vans make it possible to provide medical relief at remote places and at the accident site much faster.

POWER CARS:

These are particularly useful to provide power supply for the entire formation. In case of Rajadhani and Shatabdi expresses, provision for additional power supply is a must to cater to the needs of air-conditioning for the formation. Self-generation is not provided in these coaches; instead, these power cars will be attached to the formation and the power is taken from the End On Generation.

ON THE DEVELOPMENT FRONT…:

Stainless Steel Coach:
For the first time on the Indian Railways, two proto-types of AC Sleeper coaches with 100% Stainless Steel shell were designed and manufactured in ICF. The usage of 100% stainless steel is with a view to bring down the maintenance cost to nil and to increase the life of the coach.

Eco-friendly toilet, the BIO-TOIL:

ICF has also provided amenities in the coaches that are environmental friendly. BIO-TOIL works on the principle of bacterial de-composition by Eco-friendly bacteria injected in the system, which reduces the waste to harmless non-obnoxious liquid that gets automatically discharged on to the track.

As the requirement and the demand grow up, ICF had to go in for new developments and as a result the JAN SHATABDI came in to existence.

Jan Shatabdi coaches:

The latest development is introduction of Jan Shatabdi rakes consisting of AC Chair Car, II Class Chair Car (non-AC) and II Class-cum-Brake Van. This rake has a lot of improved features liked better seating arrangement, improved window arrangement, sub-pantry and rail-mart.

Coaches with LHB features:

It is also proposed to manufacture 2 coaches with LHB features during the production year 2002-2003.

Innovations, improvements and developments have been the way of life at ICF.