PURPOSE: To execute skew rolling of a metallic tube stably and at high efficiency.
CONSTITUTION: A skew rolling device 13 has an inclined-angle imparting motor 26 for imparting an inclined angle β to forming rolls 20, roll-driving torque detector 35 for detecting the driving torque of the forming roll 20, front tension detector 38 for detecting tensile force which is imparted to the tube 10, 16 with a draw gear 17 and control parts 39, 40, 41 means for controlling the motion of the draw gear 17 and inclined-angle imparting motor 26. The motion of the draw gear 17 is controlled by the control parts 39, 40, 41 so as to become a drawing speed V1 such as the driving torque detected with the roll driving torque detector 35 is within the max. driving torque that is allowed to the forming rolls 20 and the motion of the inclined-angle imparting motor 26 is controlled so as to become the inclined angle β at which the tensile force detected with the front tension detector 38 is in a certain range of not larger than critical breaking tension.
KIMURA TOSHIRO
TSUKAMOTO EIHIKO
SHIODA HIROSHI
MITSUBISHI HEAVY IND LTD