| 摘要 |
<p>PURPOSE:To control wall thickness surely by feeding the signals for the longitudinal movement extent of a mandrel bar measured with measuring devices to an arithmetic setting circuit, and controlling the rolling reduction of rolling rolls with the arithmetic setting device based on these signals. CONSTITUTION:In a device of rolling and making pipe by inserting a mandrel bar 2, the longitudinal movement extent of the bar 2 is detected with sensors 12, and the signals 9 based on this movement extent are fed to an arithmetic setting device 10. The device 10 operates the screw-down positions of roll screw-down cylinders 5 and adjust the screw-down of the cylinders 5 via servovalves 7 by the control signals 15 comparing said signals with set values. Therefore, the wall thickness of a pipe material 1 is automatically and uniformly controlled. In some cases, the diameter of the bar 2 is measured with a diameter measuring device 16, and the signal thereof is introduced into the device 10 which corrects the signal 15 according to the change in said diameter.</p> |
