| 摘要 |
PURPOSE:To enable efficient bulging work using cheap equipment by making a mandrel inserted into the tube movable in axial direction, and providing a truck that runs carrying the tube. CONSTITUTION:A fixing rod 19 is moved in axial direction by a rod cylinder 18. A mandrel 16 is inserted into the tube 1. A piston 4 is moved forward by supplying hydraulic pressure to a pressure cylinder 9, and a pressure rod 17 is fitted to the mandrel 16. Segmental dies 2c-2f are closed by the die cylinder of a supporting stand 27. A cylinder 15 is moved forward and a circular cylinder 14 is restrained to the segmental dies 2c-2f. Under this condition, pressure liquid is supplied into the tube 1 from an inlet hole 7, and the pressure rod 17 is thrusted against the end face of the tube 1 by the piston 4. Then, high pressure liquid is supplied to the tube 1 from the inlet hole 7. At the same time, pressure liquid is further supplied to the pressure cylinder 9, and the tube 1 is compressed in axial direction and bulged to the specified shape. |
