PURPOSE: To provide a method for controlling tension in a rolling mill by which tension is controlled with a high accuracy while restraining fluctuations in thickness.
CONSTITUTION: Tension detectors SE11-SE15 are arranged on the inlet sides of 1st - 5th stands #1-#5 and the tension detectors SE11-SE15 are connected to tension controllers 51-55. The tension controllers 51-55 are connected to screw-down position controllers 31-35 of the stands on the downstream side of the tension detectors SE11-SE15 and connected to all roll-speed controllers 61-64 on the upstream side of the respective tension detectors SE12-SE15 through adders 71-73 or without the adder. The controlled variables of screw-down position and roll speed are respectively determined based on proportional plus integral calculation values using deviations between the detected values of the tension detectors SE11-SE15 and the target values in the tension controllers 51-55 and the screw-down positions of the 1st - 5th stands #1-#5 and the roll speed at the 1st - 4th stands #1-#4 are simultaneously controlled with the screw- down position controllers 31-35 and roll speed controllers 61-64.
OI TOSHIYA
NISHIMURA FUMIO
