Five-high rolling mill

Abstract

A multi-high rolling mill is disclosed which includes an upper work roll backed by an intermediate roll and a backup roll and a lower work roll backed up by a single backup roll. Control benders are provided on each of the intermediate roll and the upper and lower work rolls. In order to optimize the control of the rolling operation for skinpass rolling and the like, the control benders for the upper work roll and the intermediate backup roll are controlled so as to effect a control of the crown sheet over the entire width of the material being rolled, while the control bender for the lower work roll controls the sheet crown of the rolled material at the lateral side end portions, resulting in a composite control substantially improving the sheet quality and preventing edge wrinkles in the material being rolled. In the disclosed embodiments, the intermediate roll has a larger drum length than a predetermined maximum sheet width of rolled material to be rolled by the work roll. The shape of sheet material is sensed by a shape detector which provides a signal to a controller which actuates the roll benders.