PRODUCTION OF CAST BILLET OF HIGH SI CONTENT STEEL FREE FROM EDGE CRACK

PURPOSE:To prevent the generation of edge crack at the time of hot rolling and to improve the yield of rolling by delivering the cast billet after continuous casting at a high temp. and rolling down the ends of the cast billet prior to heating at the time of continuous casting and hot rolling a high Si-content steel. CONSTITUTION:The high Si-content steel is continuously cast at >=1.4m/min casting speed without pouring water to a part on the upstream side from the end of a continuous casting machine. The average temp. of the section at the transverse ends of the cast billet is maintained at a high temp. of 800 to 1200 deg.C by heat retaining the cast billet in a part on the downstream side from the end of the continuous casting machine and the transverse ends of the cast billet are rolled down at >=30mm in the transverse direction before the subsequent heating of the cast billet, by which the edge crack arising at the time of the hot rolling is prevented.