| 摘要 |
PROBLEM TO BE SOLVED: To provide a method by which, when an end part of a material pipe is sealed in hydroforming, the end part can be surely sealed so as not to cause leakage of a liquid for pressurization, and at the same time, the risk of inviting appearance defects is prevented, and an increase in working costs of a pipe end sealing member is not caused and problems due to the defect of a micromachining part or the like is prevented.SOLUTION: When sealing both ends of a material pipe by a pipe end sealing member serving also as a shaft pressing member, a sealing member having a projection part for insertion having an outer diameter smaller than the pipe end inner diameter of the material pipe is used as the pipe end sealing member. A projection part for insertion is inserted into the pipe end of the material pipe, it is arranged inside a die so that the outer peripheral surface of the pipe end is in contact with the inner surface of the die, and pressurizing force in an axial direction is given to the pipe end sealing member. Thus, the pipe end of the material pipe is plastically deformed in a direction of filling a clearance between the outer peripheral surface of the pipe end and the projection part outer peripheral surface of the pipe end sealing member, and the pipe end is sealed. |
