摘要 |
<p>PURPOSE:To prevent the increase of the sheet thickness of a rolling material due to the disappearance of its back tension, by providing a variable crown roll to the prescribed stand of the 2nd stand and succeeding ones and increasing the amount of crown of the roll by the passing signal of the tail end of material through an upstream stand, in a group of plurally arranged four-high rolling mills. CONSTITUTION:In a group of plural four-high rolling mills arranged in tandem, at least one side of the backup rolls of the prescribed stand of the 2nd stand and the succeeding ones is made to be a variable-crown roll. The amount of crown of the prescribed stand is immediately increased in accordance with the pressure change produced directly after the passing of the tail end of rolling material through an upstream stand, to prevent the increase of the sheet thickness of rolling material due to the disappearance of its back tension, and the dimensions in the vicinity of the rear end of rolling material are made to the same rolling dimensions as those of other part of material, to obtain an excellent product.</p> |