Elongation control of the ultra-thin tinplate during two-stand temper rolling unsteady process

ABSTRACTThe elongation closed-loop control mode is essential for the temper rolling of the ultra-thin tin plate. During an unsteady process, the interstand tension is used for the stabilization of the elongation. But due to the drastic changes of the rolling force and rolling speed, the elongation fluctuation is beyond the tension control, which leads to the flatness degradation. In order to stabilize the elongation and the flatness, the adaptive compensation control for rolling force during the unsteady process is discussed in this work. This gain compensation for rolling force is based on the theoretical results from the rolling force model and validated from experimental results. Industrial experiments and application show the fluctuation of the elongation reduces by 90.11% during the unsteady process. Meanwhile, the change range of interstand tension reduces from 14% to less than 5%, length of the flatness degradation period decreases from over 180 m to shorter than 60 m.