| 摘要 |
PURPOSE:To prevent buckling, etc. of a bland pipe at the time of working by inserting a mandrel into the blank pipe, and thereafter, holding the inside of the blank pipe by plural claws, and also presssing an ''O''-ring, and pressure-welding it to the inside surface of the blank pipe. CONSTITUTION:A mandrel body 1 slides in the axial direction by a cylinder A, and a lever 2 is made freely oscillatable by a fluid cylinder 6 through a pin 3 of the outside periphery of a body 1. When the mandrel body 1 is advanced by an operation of the cylinder A, a core shaft 4 is held by a metallic mold C together with a body claw member 7 and inserted into a blank pipe B. Subsequently, when the core shaft 4 is moved backward by the cylinder 6, the claw member 7 holds firmly the blank pipe B from the inside through a tapered diameter expanding part 4b. In this case, an ''O''-ring 10 is deformed in the axial direction by an action of a collar 9, bulged in the diameter direction, abuts on the inside surface of the blank pipe B and seals it. Accordingly, in case of the bulging, the blank pipe B is prevented from contraction and buckling. |
