MODELING AND CONTROL OF FRONT END BENDING IN HEAVY PLATE MILLS

In this paper, a pass-to-pass control concept is presented in order to minimize the occurrence of flatness defects in form of so-called ski-ends in the hot rolling process of heavy plates. These ski-ends arise due to asymmetrical rolling conditions, i.e. different work roll circumferential speeds or vertical temperature gradients. The control concept is based on a physical model for asymmetrical rolling which is validated by numerical and measurement data. Since the drive train proves to be the suitable actuator for suppressing the ski-ends an improved underlying multi-input multi-output control concept for the two main drives will be presented.