MANUFACTURE OF STEEL

PURPOSE:To reduce operation time and to simplify converter equipment by chiefly decarburizing pretreated molten iron in a converter, sampling the resulting steel with a sublance without tilting the converter, and estimating the composition. CONSTITUTION:Molten iron is pretreated in pretreating equipment 1 to remove S, Si and P, and it is chiefly decarburized by refining in a converter 2. At this time, the blowing time can be reduced by about 1/2 of the conventional time. Whether the resulting steel is fit for discharge or not is judged by sampling the steel with a sublance 3 without tilting the converter and by estimating the composition. Since analysis is immediately carried out, the operation time can be reduced. After discharge, the steel is further refined as required at the outside of the converter.