| 摘要 |
PURPOSE:To obtain a titled device capable of rolling the bead part of a welded pipe efficiently in the circumferential direction by pressing the inner and outer surfaces of the welded pipe by a mandrel disposed in the inside of the pipe and plural revolving pressing-rolls disposed on the outer circumference of the pipe. CONSTITUTION:A mandrel 21 having the outer diameter approximately the same as the inner diameter of a welded pipe A is disposed in the inside of the pipe A, and is reciprocated between the groups 14, 15 of the 1st and 2nd sizing rolls through a mandrel holding bar 23 and a supporting arm 24. On the other hand, plural pressing rolls 30 are disposed around the pipe A by leaving a space between them, and are freely revolved on the outer circumference of pipe A while maintaining said space as well as reciprocated in the longitudinal direction of pipe A in synchronization with the mandrel 21. In this way, the pipe A is rolled in its circumferential direction by pressing a bead part (a) with the aids of mandrel 21 and rolls 30. Further, it is preferable to form a notch on the mandrel 21 and to dispose the rolls 30 so that the rolls 30 are equally spaced and have each a small leading angle with respect to the feeding direction of pipe A. |
