SAIL Supplied 30,000 Tonnes of Special Steel for Vikrant
Strategic Research Institute
Published on :
5 Sep, 2022, 6:32 am
Indian Navy has created maritime history by commissioning the prestigious Indigenous Aircraft Carrier Vikrant in a ceremony solemnized by India’s Prime Minster Mr Narendra Modi at Cochin Shipyard in Kochi in Kerala. Designed by Indian Navy's in-house Directorate of Naval Design and built by Cochin Shipyard, the carrier is christened after her illustrious predecessor, India's first Aircraft Carrier which played a vital role in the 1971 war. The 262 meter long carrier has a full displacement of close to 45,000 tonnes which is much larger and advanced than her predecessor. The ship is powered by four Gas Turbines totaling 88 MW power and has a maximum speed of 28 Knots. Built at an overall cost of close to INR 20,000 crores, the project has been progressed in three Phases of contract between MoD and CSL, concluded in May 2007, December 2014 and October 2019 respectively. The ship's keel was laid in February 2009, followed by launching in August 2013. It has an overall indigenous content of 76%. With the delivery of Vikrant, India has joined a select group of nations US, UK, Russia, France & China having the niche capability to indigenously design and build an Aircraft Carrier. Indian steel giant Steel Authority of India Limited supplied about 30,000 tonnes of steel in high grades for building of Vikrant
Vikrant has been built with high degree of automation for machinery operation, ship navigation and survivability, and has been designed to accommodate an assortment of fixed wing and rotary aircraft. The ship would be capable of operating air wing consisting of 30 aircraft comprising of MIG-29K fighter jets, Kamov-31, MH-60R multi-role helicopters, in addition to indigenously manufactured Advanced Light Helicopters and Light Combat Aircraft Navy. Using a novel aircraft-operation mode known as STOBAR, Short TakeOff but Arrested Landing, Vikrant is equipped with a ski jump for launching aircraft, and a set of arrester wires for their recovery onboard. The height of the new ship, keel to pole mast, is 61.6 meters. The flying deck is around 12,500 square meters, roughly the size of two and a half hockey fields. Cabling on board is 2,600 kilometers long.
A major spin-off of this is the development and production of indigenous warship grade steel for the ship through a partnership between Navy, DRDO and Steel Authority of India Limited, which has enabled the country to become self-sufficient with respect to warship steel. Warship steel is a challenging specialty grade having required hardness, toughness & ductility at up to minus 60 degrees Celsius al0ong with superior corrosion properties.
Defence R&D Organization took up a project in 1999 to develop and mass-produce warship grade steel. Russia provided the chemical formula of warship steel called ABA, which was mastered by SAIL at its plant at Bhilai, Rourkela, Bokaro & Durgapur. Rourkela Steel Plant found that tempering and quenching gave the required grain structure and then in a breakthrough Bhilai Steel Plant developed it through continuous casting process and warship grade steel is now affordable.
Bhilai Steel Plant supplied bulk requirement of warship steel plates, while Rourkela supplied super thick plates through quenching and tempering. INS Vikrant used three special steels grades, DMR 249A for the hull & body, DMR 249B for the flight deck & DMR Z2S was developed for the floor of compartments that housed heavy equipment like engines and generators for absorbing the compression and decompression from the heavy equipment. In the pipeline now is DMR 292A, which will be used for the hull of submarines for submarines that will be built under Project 7S. Now all the warships being built in the country are being manufactured using indigenous steel.