MOLD FOR HYDROFORMING

PROBLEM TO BE SOLVED: To obtain a mold for hydroforming, which generates no crack in itself, causes no transferring of split lines of cores, can form a product with a small corner radius, is manufactured at a low cost, and has a simple structure. SOLUTION: The mold for hydroforming is horizontally splitted and consists of upper and lower core-molds 5 which face each other when mold clamping, and upper and lower outside-molds 1 holding the core-molds. The upper and lower core-molds 5 are brought into close contact and combined with the outside-molds 1 only at flat faces 11 including the outer periphery of a butting part 7. In either or both of a cross section in a tube-axial direction and a cross section in a peripheral direction, the angle that the flat faces 11 make with each other is >0° and