| 摘要 |
<p>PURPOSE:To prevent an end part from flaring and to improve product accuracy by so controlling the longitudinal moving speed of a pipe material during rolling of its end part as to increase said speed. CONSTITUTION:A moving speed setter 8 controls the driving of a driving motor 4 by a set signal 9 during rolling of the end part of a pipe material 2 thereby changing and adjusting the moving speed V for forcing in of a mandrel 3 at a prescribed speed pattern. Further, the position signal 11 from a position detector 10 detecting the longitudinal position of the material 2 and the screw down force signal 15 from a load cell 14 provided in the chock 13 of rolling rolls 12 are introduced into the setter 8, which in turn adjusts (corrects) the speed pattern. Thereby, the speed pattern which is so arranged as to increase the moving speed V for forcing during rolling of the end part of the material 2 is introduced to the setter 8 and the material 2 of the same diameter is rolled.</p> |
