Advanced measurement and flatness control for hot strip mills

Abstract

The efficiency of automatic flatness control systems in hot rolling mills is based mainly on the capability of the installed instrumentation to provide accurate flatness measurements, on accurate prediction models, and on the selection of an optimum control concept. BFI, together with Thyssen Krupp Stahl, has recently developed a new topometric flatness measurement device (called TopPlan) and advanced flatness control strategies (providing time delay compensation, systematic analysis of shape errors and exact distribution of shape coefficients to be controlled by actuator sets) that offer advantages over conventional techniques and lead to significant improvements in hot rolling processes and strip shape. The present article aims to demonstrate the principles and advantages of these technologies.