Digital control system for a rotary crop shear

Digital control systems with varying degrees of sophistication, are finding increasing applications in the steel industry. The authors outline one such system which has replaced the rather dated speed control equipment for a rotary crop shear. In addition to the usual features associated with digital control, the type of controller used retains some of the well appreciated features of the analogue controllers. The rotary crop shear, located between the roughing and finishing sections of the hot strip mill, crops the `head´ and `tail´ ends of the strip before the strip enters the finishing mill. Basic operation of this shear is described