| 摘要 |
<p>When two workpiece strands (14, 16) pass through a roll gap between two grooved working rolls (10, 12) on a roll stand to be rolled, the trailing end of one of them may leave the rolls to change the roll gap. At that time screw-down devices (20, 22) on each side of the roll stand are controlled to adjust the roll gap at least at the position of the remaining workpiece. Also in a multi-strand tandem rolling mill, rolling speeds on roll stands upstream of a roll stand from which one of the strands has departed are changed by a speed ratio of (1-b2)/(1-b1) where b1 and b2 designate the rates of backward slips in the presence of the two strands and in the absence of one of the strands on the last-mentioned roll stand. Alternatively roll speeds on roll stands downstream of that roll stand may be changed by a speed ratio of (1 + f2)/(1 + f1) where f1 and f2 designate the rates of forward slip which correspond to the b1 and b2 respectively.</p> |
