| 摘要 |
<p>PURPOSE:To prevent the bending and outside diametral fluctuation at the end of a seamless pipe and to improve the yield thereof by controlling the number of revolutions of rolls of each stand in accordance with the calculated result of the force acting axially on the seamless pipe between stands. CONSTITUTION:The difference between the outputs from load cells of tension detectors 31, 32 provided to the 3rd stand 13 of a sizer 1 and the difference between the outputs from the load cells of the tension detectors 41, 42 of the 4th stand 14 are inputted to an arithmetic control part 60 in the stage of rolling the seamless pipe 2 with the rolls 23, 24 of the stands 13, 14. The above- mentioned differences between the outputs are the axial force acting on the pipe 2 in the stands 13, 14. The control part 60 calculates the difference between both differences in the outputs to determine the axial force acting on the pipe 2 between the stands 13-14 and controls motors 51, 52 so that the acting force attain is the set value of a setter 61. More specifically, the numbers of revolutions of the rolls 23, 24 are controlled by the motors 51, 52 so that the tension and compressive force do not act on the pipe 2 between the stands 13 and 14.</p> |
