Patent ID: 6868707
Filing Date: 2005-03-22
Classification: B21B

Abstract:
1. A rolling method for a strip rolling mill, the strip rolling mill including a pair of upper and lower work rolls for rolling a strip of material, intermediate rolls for supporting each of the work rolls, back-up rolls for supporting each of the intermediate rolls, a work roll drive mechanism for moving the work rolls in directions of work roll axes, and an intermediate roll drive mechanism for moving the intermediate rolls in directions of intermediate roll axes, wherein each of the work rolls is provided with a tapered portion near one end thereof and the tapered portions of the work rolls are arranged on opposite sides of roll bodies thereof with respect to roll axis directions, the rolling method comprising the steps of: repeating a reversible rolling by reversing a rolling direction of the strip or material; and during the repeated reversible rolling, in order to allow an average of an actual edge drop value and a target edge drop value in at least one coil being rolled to almost agree, fixing axial positions of the work rolls at desired positions so that the work rolls are not axially moved and points at which the tapered portions of the work rolls start are within a width of the strip of material, and changing axial positions of the intermediate rolls to control a thickness distribution in a width direction of the strip of material being rolled.