PROCESS FOR MANUFACTURE OF TRANSFORMER STEEL Russian patent published in 1994 - IPC

FIELD: metallurgy. SUBSTANCE: this process includes such steps as melting and casting of steel, heating of slabs to point of 1240 to 1320 C and double hot and cold rolling followed by thermal treatment. Second hot rolling is conducted at temperature of 900 to 1150 C with reduction of 80 to 90 % . Steel product is subjected to second hot rolling with difference between relative interpass reductions not exceeding 5 % and at rate not higher than 0.5 m/s. In second pass, rate of rolling is 1.2 to 2 times as high as that in preceding passes and amounts to 4 to 12 m/s. EFFECT: more sophisticated technique. 2 dwg, 2 tbl