| 摘要 |
PROBLEM TO BE SOLVED: To obtain a formed product excellent in quality without any underfill by arbitrarily setting a back pressure to be applied to a counter punch in accordance with a work. SOLUTION: In this die device for fully enclosed forging by which cavities 1a, 2a are enclosed between an upper die 1 and a lower die 2, by pressing/ branching a work 7 in the cavities 1a, 2a with an upper counter punch 8 and a lower counter punch 22, the work 7 in the cavities 1a, 2a is subjected to fully enclosed forging, pressing means 11, 19, in which the cavities 1a, 2a are both side-enclosed by pressing the upper die 1/lower die 2 from up/down directions, are arranged, a back pressure imparting means, in which the work 7 is both side-branched by imparting a back pressure smaller than a forming load to upper/lower counter punches 8, 22 in forming, is arranged above the upper counter punch 8 and below the lower counter punch 22, the back pressure imparted by the back pressure imparting means is arbitrarily set in accordance with the work 7 by a back pressure setting means, by arbitrarily setting corresponding to the work 7, the formed product excellent in quality without any underfill is easily obtained.
|
