Experience with resin-bonded magnesia carbon bricks in AOD converter vessels for the production of stainless steels

Krupp Thyssen Nirosta GmbH in Bochum has steadily optimized the AOD process since its introduction in 1972 to produce stainless, acid- and heat-resistant steels. The accompanying process-related changes have also necessitated the optimization of the hitherto dolomite-bricked lining of the blowing converter vessels. The main wear zones of the converter vessels are located at the trunnions. It is in these zones that resin-bonded magnesia carbon bricks have been successfully tested. The bricks, because of their good resistance to infiltration, display a high durability towards the varying slag behaviour caused by the process at the prevailing high temperatures. As early as in the first trials the zonal lining of MgO-C bricks yielded positive results and has consequently been adopted as the standard lining. The mean life expectancy has been increased by 20%. It has thereby been possible to also increase the availability and the productivity of the converters at the steel plant in Bochum.