Durgapur Steel Plant (DSP) of Steel Authority of India Ltd (SAIL) has won the appreciation of the Indian Railways for developing and starting supplies of special ‘S’-shaped loco wheels six months in advance of planned despatch. While stating that the “Railways required this item very urgently” to keep its “EMD fleet running”, the Railways’ Diesel Locomotive Works (DLW) at Varanasi has acknowledged the “painstaking efforts undertaken” by the collective of DSP’s Wheel & Axle Plant to satisfy their customer’s requirements. The Railways have so far been importing this type of wheel from Japan and the Czech Republic.
In May 2006, the Railways had asked SAIL to take up the challenge of manufacturing 120 ‘S’-shaped wheels with 208 mm bore dia to suit diesel electric locomotives (EMD) of 4,000 horsepower. As per plan, DSP was scheduled to start supplies for this order from March 2007. However, learning of the Railways’ urgent need to pre-pone the deliveries, the SAIL management immediately initiated action, leading to supplies starting on 13th September 2006 itself. All ordered wheels have been manufactured and despatches to DLW, Varanasi will be completed within this month itself.
This ensures complete indigenisation of latest design wheels – from designing to manufacturing.
The ‘S’-shaped web plate heat resistant high axle load rolled wheel for broad-gauge locomotives developed by DSP’s Wheel & Axle Plant is capable of withstanding higher brake heat loads and heavy axle loads. Finite element analysis of the S-profile wheel has shown that it gives almost 50% less thermal stress and up to 15% less mechanical stress compared to the straight plate wheels of 3,000 horsepower used in existing locos. The new design will permit an additional 3-5 months wheel-life for locos.
DSP manufactured 44 prototype S-shaped wheels and supplied to South Eastern Railway for trial fitment in locomotives in April 2004. The performance of wheels fitted in the locomotives was found to be satisfactory. Further, 14 wheels sent to RDSO for testing by brake dynamometer also tested OK.
The first commercial assignment has been tested by the Railways’ inspection agency RITES and Railways representatives with 100% online testing.
SAIL has always responded to the Railways’ needs with alacrity, taking special care on every occasion to meet the most stringent demands of its most prestigious customer. The Railways, too, on its part has been reciprocating this gesture by making wagons available for the huge transportation needs of SAIL.