CONTINUOUS ANNEALING OF COLD ROLLED STEEL STRIP BY INTERNAL ROLL COOLING

摘要

A method of cooling band or hoop steels with hollow cooling rolls through which a cooling medium flows to absorb the heat of the steel strips trained about and in contact with the hollow cooling rolls, thereby cooling the steel strips. According to the invention this method is carried out so as to fulfil the following equation (1) with the cooling roll having a diameter D600 mm when a thickness h of the steel strip is within 0.2/=h0.6 mm, DELTA TS0.65x sigma T1.5x theta xh-0.75 (1) and so as to fulfil the following equation (2) with the cooling roll having a diameter D1,000 mm when a thickness h of the steel strip is within 0.