| 摘要 |
PURPOSE:To obtain a titled part free from uneven distortion at low working load, by heating dies and a punch to a temperature equal to the temperature of a blank, and performing preliminary forming and final forming of the blank successively by the punch. CONSTITUTION:For instance, in forging a turbine part having long fin 1, a punch 6 and raising, dividing and lowering dies 3, 4, 5 are heated by a heater to the forging temperature of a blank 2. The punch 6 and die 3 are raised and the blank 2 heated separately to the forging temperature is inserted into a die cavity 7. Then, the die 3 is lowered and the die 4 is fixed and the punch 6 is lowered to press the whole face of the rear end of the blank 2. Preliminary forming is performed by plastic deformation thrusting the tip of the blank into the cavity 7. A punch 61 that replaces the punch 6 and heated to the forging temperature is lowered, and only the center of the blank 2 is pressed. Other part is fixed by a holder 11, and final forming is performed. By this way, only a part of the blank 2 near the fin 1 forming part is plastically deformed, and an objective part is obtained. |
