Team Salute reports that more than 80,000 tonnes of “Marine grade” steel worth over Rupees 625 crores produced by Indian industry has been already picked up by Indian shipyards.
Making steel involves processing iron ore to rid it of impurities. It has to be smelted in furnaces at very high temperatures and then quenched and tempered to ensure good quality steel. But for the ships of Indian Navy, the steel has to be of “Marine Grade”, strong yet flexible, free from distortions and resistant to the corrosive action of salt water and built to last at least 30 years. India’s indigenous Aircraft Carrier-1 (IAC), christened INS Vikrant , is the first Indian naval ship to be built using steel, predominantly made by the Steel Authority of India (SAIL). The carrier with much of its propulsion machinery, gearboxes, alternators, pumps, pipes and air conditioning installed and under integration, is berthed at Cochin Shipyard Limited (CSL) awaiting completion of the flight deck and the “Island Complex”. If all goes well, the ship will begin harbour trials and then sea trials in a stipulated period. What is important is that, India had finally called an end to imported marine grade steel, whether from Russia, Sweden, Germany or elsewhere. But technologies in this field are jealously guarded, difficult to acquire, expensive and hard to reverse engineer successfully
THE QUEST FOR MARINE GRADE
High quality steel for defence equipment in India was bring produced for several years. SAIL’s Rourkela plant (RSP) for example, produced steel for the Ordnance Factory Board. These included special steels which offered protection to soldiers from rifle bullets and armour plating of infantry combat vehicles. The Spade M1 steel was made for armouring main battle tanks, initially T-72 M1, and more recently, the T-90. To enable these armour steels to provide the required ballistic resistance, the steels were quenched and tempered at a special plant, dedicated to this task, in RSP. While RSP manufactured the plates of armour steels, the steelmaking (of these special medium carbon low alloy steels) was carried out at the Alloy Steel Plant (ASP), Durgapur.
But developing marine grade steel was difficult and challenging and in the late 990s, indigenizing manufacture of marine grade steel became high priority as the Indian Navy’s ship building programme gathered steam. Indian shipyards were spending several crores of rupees on importing marine grade steel. The construction of the first Air Defence Ship (as the IAC was known then) could not take off as it was facing major delays because of difficulties in procuring high quality marine grade steel. It was at that stage the Navy had approached DRDO to take up indigenization of this grade steels. Efforts at developing marine grade steel had been on since the 1980s at the Defence Research and Development rganisation’s (DRDO) laboratories, namely the Defence Metallurgical Research Laboratory (DMRL), Hyderabad and Naval Materials Research Laboratory (NMRL), Ambernath. The DRDO had set up a task force. SAIL had also involved people from each of its plants to discuss and resolve all issues relating to developing military steel of all grades. It had now become a “national strategic project” which had to be done and eferably at the lowest cost possi le! In many cases, there may be a requirement for the government to invest in industrial infrastructure for specialized melting furnaces, forge press, rolling facilities and heat treatment plants, to mention a few typical cases. The DRDO will do its best
to develop the technology for high performance specialty materials that are essential to further the cause of “Make in India”.