By K K Pahuja,
The Indian government’s ambitious programme of manufacturing 400 new Vande Bharat trains, announced in the Union Budget, is set to change the way people travel in the country. These modern train coaches will provide a new level of safety and comfort with enhanced speed. However, the recent tenders floated by the Indian railways for these trainsets have considered aluminium as the material of choice instead of stainless steel. It is presumed that aluminium coaches may reduce the weight of the coaches and save propulsion energy. However, when other prominent parameters are weighed, stainless steel emerges as the best fit to this project, and to the government’s vision for the Railways. Here’s why- stainless steel,
During the late nineties, the Indian Railways adopted the German LHB coach design in stainless steel, with the first coach being manufactured in lndia around the year 2000. These coaches have stood the test of time in terms of safety, economy, and hygiene. This prompted Railways to completely shift its production to 100% stainless steel coaches in all the three coach factories- ICF, RCF and MCF, in 2017. Over time several vendors have been developed by the coach factories for supply of major stainless steel components and assemblies like sidewalls, end walls, trough floor sole bars, cross member roofs, etc. With timely support from the domestic stainless steel industry and its associates, an elaborate ecosystem for manufacturing modern stainless steel coaches has emerged in the country. The coach factories, or their vendors, are not forced to rely on importing stainless steel for developing LHB shells, as the domestic manufacturers are equipped to fulfil the Indian stainless steel demand. Additionally, Railways’ vendors have enhanced their manufacturing techniques to provide the best-in-class coaches that suit the requirements of the Indian railway lines. As a result, the coach factories have successfully churned out record numbers of LHB stainless steel coaches.
As mentioned earlier, the concern surrounding weight reduction is often emphasized upon by the advocates of aluminium railway coaches. It is noteworthy that these are already accounted for in the existing stainless steel specifications of RDSO (based on German specifications). The reduced weight is enabled by incorporating higher strength of stainless steel for shell components. This design logic is already adopted in the Indian metro coach shells that do not require painting and have the highest resistance to corrosion, fatigue, and impact. Corrosion resistance of aluminium is much inferior in coastal areas. Additionally, from an environmental point of view, stainless steel offers 100% recyclability and better end-of-life value as compared to aluminium.
Aluminium is used for developing coach shells in Europe, China and Japan for very high-speed coaches (over 200 km/hr) with lesser number of coaches per train, unlike Vande Bharat trainsets. Presently, the Indian railway tracks permit a maximum operation speed of 130 kmph. A speed upgradation to 160 kmph (and later 180kmph) is in progress, that too only on a few selected routes. The prominent rail and metro coach suppliers in India (BEML, Alstom, Bombardier, ICF, RCF, and MCF) have no experience in fabrication of aluminium coaches. Moreover, the aluminium honeycomb-type box section used in coaches is not developed in India, leading to a heavy import-dependence. Not to forget the CO2 emission per tonne in Aluminium production, which is almost 5-6 times of stainless steel.
On the life cycle front, stainless steel coach shells have a life of above 50 years. However, it is much less for aluminium coach shells due to fatigue and negative camber issues. It is, therefore, not surprising that bidders are asking for maintenance clause to be changed from 35 years to 15 years.
Stainless steel coach shells on LHB platform are well established in lndia with nil imports and no bottlenecks in supplies to coach factories from established vendors, which can enable faster roll out of Vande Bharat trainsets. There is a substantial scope for weight reduction in the LHB shells design with high strength austenitic stainless steel, whose specifications already exist at RDSO.
Indian Stainless Steel Development Association (ISSDA) has submitted these facts to the Ministry of Railways and Indian Railways officials, and has urged the authorities to consider them for an effective execution of the Railways’ modernisation plan. While Aluminium coaches may be suitable for the new high speed bullet train network, Vande Bharat trains on the existing network can be expanded cost effectively with stainless steel coaches. There is also a considerable scope of weight reduction in the coaches with improved designs and high strength stainless steels.
(The author is President- Indian Stainless Steel Development Association (ISSDA). Views expressed are personal and do not reflect the official position or policy of the FinancialExpress.com.)