METHOD FOR RESTORING OPERATING PROPERTIES OF ROLLS IN HOT ROLLING MILLS Russian patent published in 1997 - IPC

FIELD: metallurgy, hot rolling practice. SUBSTANCE: proposed method comprises step of heating roll surface up to tempering temperature, followed by cooling step. Heating is effected in process of roll operation due to contact of its surface with metal being rolled, while, simultaneously, subjecting roll to gradual cooling. Cooling down from tempering temperature is effected in two stages, namely: first slowed-down cooling, next accelerated cooling. , tempering step being effected during period equal to 50-20,000 cycles/rotations of roll. To avoid interference with rolling procedure, tempering step is effected during shut-downs of rolling mill. According to present method, rolls of two-high rolling stand and those of section mill stand are subjected to heating up to roll surface temperature not higher 530 C, and those of four-high rolling stand not higher than 400 C. EFFECT: increased wear resistance of working rolls due to lessened depth of regrinding operations effected to remove cracks caused by roll surface erosion. 5 cl, 3 tbl