| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a ring rolling mill which can increase productivity.SOLUTION: A mandrel 1 comprises a columnar mandrel pin 10 through which a work-piece is inserted, and a mandrel main body 15 which can axially move the mandrel pin 10. A prism part 13 of a prismatic shape is provided to one end of the mandrel pin 10, a female thread is provided in an axial direction in the prism part 13, and the mandrel main body 15 is provided with an engagement hole 16b in which the prism part 13 is engaged. The mandrel pin 10 is fastened to the mandrel main body 15 by a bolt 50 having a male screw 50a engaging with the female thread in the prism part 13.</p> |
