Load distribution ratio as a benchmark for flatness using predictive control

Shape control involves regulation of the internal stress in rolled strip so that when it is cut into sections it will lie flat on a flat surface. The paper presents two approaches to shape control in metal rolling applications and develops methods of assessing the quality of shape, or flatness control, so that it may be improved. Two particular cases of shape control in hot strip mills are considered and are compared against a newly defined benchmark. Finally, simulation results are presented to illustrate the techniques.