Mumbai: The six million commuters who travel on Mumbai’s suburban railway system every day could have a safer ride in the future.
Indian Railways is using special grades of stronger and fire-resistant plastic for seats and interior wall panelling in its 157 new trains that will be rolled out over the next two to three years in Mumbai. The first such train rolled out on 12 November.
These special grades of plastic are replacing conventional materials such as glass, wood and metal. Seats made of polycarbonate resins will replace the old wood and metal seats, while fibre-reinforced plastic will replace cheap, plastic-laminated sheets which are used as interior wall panelling. Traditionally, plastic usage in railway coaches did not exceed 5-6% of an empty train’s weight. However, the use of special types of engineering plastic in windows and seats means plastics will account for 8-9% of the total weight in the new coaches. Plastic composites are typically lighter than mild steel.
The transition hasn’t been cheap, but in part it’s been helped by the turnaround of the railways, which now has money to use more modern materials across a rail network that is one of the most extensive—and oldest—in the world.
Engineering plastic is about two to three times more expensive than steel on account of its processing costs, since the tools and dies to make the moulds are pricey. The use of plastic materials in the 75 new trains, with 12 coaches each, will cost about 10% of the entire makeover cost pegged at Rs900 crore, according to an Integral Coach Factory (ICF) official who didn’t want to be named. ICF, a production unit under the ministry of railways, has been entrusted with the design and manufacture of Mumbai’s new suburban trains.
Engineering plastic can also replace glass, wood and metal used in doors, windows, roof interiors and partitions in the railway coaches. Had it not been for the high cost and limitations in processing, plastic composites can theoretically replace an entire coach itself, this official pointed out.
The local arms of Sabic Innovative Plastics Holding BV and Bayer MaterialScience AG are providing plastic materials for the seats, while Hindustan Fibre Glass Works, Kemrock Industries and Exports Ltd, and Kineco Pvt. Ltd are supplying plastic for the interior wall panelling, said another ICF engineer who didn’t want to be named as he is not authorized to speak to the media.
“For seats, we have developed a special fire-retardant grade of our special polycarbonate resins that meet their stringent fire standards on flammability and toxicity. Due to its high strength and superior impact-resistance properties, it is capable of taking load and is resistant to vandalism,” says K. Venugopal, president and CEO of Sabic Innovative Plastics India Pvt. Ltd.
Sabic has also replaced the conventional materials with its fireproof polycarbonate resins in such items as centre tables, destination boards and signal lenses. “Our involvement with railways has increased multifold in the last two to three years and we have seen tremendous drive in modernization, safety, comfort and aesthetics from railways,” said Venugopal.
Ravi Krishnan in New Delhi contributed to this story.