March 20, 2002

   The maintenance unit of the Bokaro Steel Plant (BSL) of the Steel Authority of India Ltd. (SAIL) has taken up a major inhouse repair of the trunion shaft of the converter (i) in Steel Melting Shop (ii) saving about Rs. 23 crore to the plant. Such repair was never taken up before in this part of the world. The repair of the shaft has also helped the plant to keep up its production intact.

    Bulk of hot metal produced in BSL from its blast furnace is converted into steel through SMS-II, which is equipped with two 300 tonne capacity converters. These are the largest of their kind in the country and two of the 26 such converters were supplied by the erstwhile USSR.

    Recently Converter No.1 suffered a major breakdown where the trunion shaft and both the bearings on it were found completely damaged. The trunion shaft takes the full load of converter with hot metal and moves in both directions on bearings. Each converter weighs around 1900 tonnes of which refractories comprise around 700 tonnes. The damage to the shaft and bearing stopped the converter movement and converter operation.

    By the excellent teamwork and the innovative ability of the maintenance staff, the converter was brought back into operation successfully as per planned date. A high degree of accuracy was maintained during the entire operation. The maintenance unit left no stone unturned to avert a no converter situation. The revolutionary technique evolved by BSL for repair of such magnitude is a historic step.