| 摘要 |
PURPOSE:To decrease cost and prevent generation of flaws on the surface of a pipe material by forming a cylindrical collet out of MC nylon and forming the periphery of an intermediate part in contracted diameter shape excepting both end parts in the lengthwise direction so as to make contact, with pressure, with the inside periphery of the pipe material. CONSTITUTION:After engaging and setting a pipe material A in a collet 2, the end taper 41 of a tail stock 4 is inserted into the end of the insertion hole 32 of a tail bush 3. Hereby, the tapered end faces of both end large diameter parts 21, 21 of the collet 2 contact with the tapered faces 21a, 31 of an expanded part. Further when the tail bush 3 is pressed by the tail stock 4, both end faces of the collet contact with the inside periphery of the pipe material A with pressure and a jig temporarily supports the pipe material. Further for release, the tail stock 4 should be retreated so as to release the expanded condition of large diameter parts 21, 21 of the collet 2. In this way, the cost of the collet 2 can be reduced and the flaw doesn't occur on the surface of the pipe material A. |
