| 摘要 |
In the method of fabricating a bellows (2) by bulge forming, an annealing step is carried out during the bulge forming process of the bellows (2) so that the capability of the material to elongate is recovered, and the workability of the bellows is improved in effect. In particular, the ratio of the outer diameter (D1) to the inner diameter (D2) can be made greater than a value that can be achieved by a single forming step. Therefore, the deflection (stroke) of each annular bulge (2a) or pleat can be increased for a given stress or the number of annular bulges (2a) and the length of the bellows (2) can be decreased for a given stroke of the bellows (2). <IMAGE> |
