METHOD OF PRODUCING THIN STEEL SHEETS HAVING PROCESSABILITY

摘要

PURPOSE:To make a hot rolling stage compact and to obtain a thin steel sheet without the need for a cold rolling stage and a cold rolling and annealing stage by installing a coil box, large draft rolling mill with a lubricator and high speed rolling with a lubricator behind a continuous casting machine. CONSTITUTION:A cast strip (or ingot) is continuously fed to the coil box 1 and is temporarily coiled. The stock uncoiled from the box 1 is fed to the large draft rolling mill 2 with the lubricator where the stock is rolled under such strong lubrication where the stock is rolled under such strong lubrication as to make the reduction ratio of rolling load >=30% at 1,100-700 deg.C. The steel strip after such rolling is fed to the high speed rolling mill 3 with the lubricator where the strip is rolled at a high rolling speed of >=1,500m/min under lubrication at the Ar3 transformation point - 300 deg.C. The rolled thin steel sheet is coiled by the coiler 5. The thin steel sheet having excellent workability is thus obtd.