Optimal Cluster Mill Pass Scheduling With an Accurate and Rapid New Strip Crown Model

Besides the requirement to roll coiled sheet at high levels of productivity, the optimal pass scheduling of cluster‐type reversing cold mills presents the added challenge of assigning mill parameters that facilitate the best possible strip flatness. The pressures of intense global competition, and the requirements for increasingly thinner, higher quality specialty sheet products that are more difficult to roll, continue to force metal producers to commission innovative flatness‐control technologies. This means that during the on‐line computerized set‐up of rolling mills, the mathematical model should not only determine the minimum total number of passes and maximum rolling speed, it should simultaneously optimize the pass‐schedule so that desired flatness is assured, either by manual or automated means. In many cases today, however, on‐line prediction of strip crown and corresponding flatness for the complex cluster‐type rolling mills is typically addressed either by trial and error, by approximate deflec...