TENSION CONTROL DEVICE

PURPOSE:To diminish the fluctuation of dimensions of material at the exit side of the final stand and to obtain the products of high quality by operating tensions as going in order to the upstream side on the basis of a fixed tension at the exit side of the final stand and a looper. CONSTITUTION:The forward tension ti at the (i) stand is cul-operated by inputting the torque deviation Gi+1 at the (i+1) stand on the downstream side by the torque and tension conversion circuit for the (i+1) stand. The determined forward tension ti at the (i) stand is controlled as to be the target tension tRi by the tension control circuit 16 for the (i)-(i+1) stand. The obtained forward tension ti at the (i) stand is input in the torque conversion circuit 158 for the (i) stand and the component torque Gi of forward tension at the (i) stand due to the ti is operated. In the same way, the torque deviation Gi at the (i) stand on the downstream side is input and the forward tension at the (i-1) stand is operated by the torque/tension conversion circuit 60 for the (i) stand. And the forward tension ti-1 at the (i-1) stand is controlled so as to be the target tension tRi-1 by the tension control circuit 6 between the (i-1)-(i) stand.