Patent ID: 6619087
Filing Date: 2003-09-16
Classification: B21B

Abstract:
A strip rolling method applied to a multi-roll strip rolling mill of not less than four rolls including at least a top and a bottom backup roll and a top and a bottom work roll, comprising the steps of:prior to rolling operation tightening the top and the bottom backup roll and the top and the bottom work roll by roll positioning devices under the condition that the backup rolls and the work rolls come into contact with each other; measuring thrust counterforces in the axial direction of the roll which acts on all the rolls except for the backup rolls; measuring roll forces acting in the vertical direction of on all of the backup roll chock of the top and the bottom backup rolls; setting an absolute value of the force of roll balance devices or roll bending devices, which give forces to the chocks for which thrust counterforces are to be measured, at a value not more than Â½ of the force of the roll balanced condition, preferably at zero; finding one of or both of the zero point of the roll positioning devices and the deformation characteristic of the strip rolling mill according to the measured values of the thrust counterforces and the roll forces of the backup rolls; and conducting roll forces setting and/or roll forces control according to the thus found values when rolling is actually carried out.