| 摘要 |
<p>PURPOSE:To facilitate the continuous rolling of the pipes which are butt-welded at the ends in the axial direction and also the simultaneous rolling of the pipes which are under different rolling schedule. CONSTITUTION:A roll diameter, pipe shape, initial length, speed reference and schedule are set by setting devices 7, 8, 9, 13, 16. By detectors 6, 11, the rotational speed of the roll and the ends of the pipes at the entrance side of a starting stand are detected. By an arithmetic device 10, based on the set value of the pipe shape, elongation and length at the time of passage through each stand is calculated. Based on the above set value, detected value and arithmetic value respectively, a timing when a part to be welded reaches just below each stand is calculated by an arithmetic device 12, and a timing to start correcting the speed of each stand downstream is determined; the speed correction of each stand in the downstream side of welding part, to the extent that tension is not actuated to the welding part and that a speed ratio among each stand can be maintained, is calculated by an arithmetic device 14. The speed of each stand is corrected at the speed correction timing and in accordance with the extent of the speed correction by an arithmetic device 15.</p> |
