| 摘要 |
PURPOSE:To enable a lower punch shorter even in the case of forming a long- sized material so that the buckling of the lower punch is averted and the operation is made easier by specifically constituting the lower punch and mandrel and adopting a lower taking out system for taking out of a pipe after forming. CONSTITUTION:The mandrel 13 is freely vertically slidably penetrated in the lower punch 11 and is attached to a frame 14 of the titled device provided with the mandrel 13 running vertically in a forming rubber mold 7 between the upper and lower punches 9 and 11 which close the top and bottom end of a forming vessel 1. The lower punch 11 and the frame 14 are made respectively independently liftable along a vertical frame 4 by cylinders 15, 16. Powder 19 is put into the mold 7 and is subjected to press forming. The forming axial force exerted to the punches 9, 11 is directly transmitted via a back up cylinder 18 to a yoke frame 17. The frame 17 is opened upon ending of the forming, then the punch 11 and the mandrel 13 are lowered. The pipe 20 is placed on the punch 11 and is removed downward from the vessel 1. The mandrel 13 is then lowered and is removed from the pipe 20.
|
