Electric Drive for the Looper of the Rolling Mill in Providing the Required Tension of the Metal Strip

The article describes the method of controlling the electric drive of the electromechanical looper (loop holder) at the moment the strip enters the gap of the finishing group of the hot rolling mill. An automatic strip tension control system with an indirect control principle is considered. The results of mathematical modeling of the electric drive of an electromechanical looper as a component of an automatic control system are presented. It is shown that at the moment the strip enters the inter-stand gap, to ensure the positioning of the loop holder and being in the allowable zone of the angle of rotation, a short-term forcing of the electric drive torque is required. The conditions are described under which the looper is in an equilibrium state, when the moment of the electric motor balances the moment of resistance on its shaft, determined by the force arising due to the tension of the strip.