PURPOSE: To reduce the load to a die when a bottoming container having a bottom of a prescribed shape is formed.
CONSTITUTION: A punch 3 and a blankholder are equipped on an upper die 2 of a press. A die 6 and a knockout 7 are equipped on a lower die 5. A projecting part 8 is equipped on the nose of the punch 3. A flat plate shaped work W1 is mounted on the die 6 to press the blankholder. When the punch 3 is dropped, the projecting part 8 is abutted on the work W1 to project the work W1 and to form a prescribed ununiform part of plate thickness at a position to make a bottom part. When the punch 3 is dropped further, the shoulder part of the large diameter part of the punch 3 is abutted on the work W1, the work W1 is squeezed between the punch 3 and the die 6 to form the bottoming container W2. Since the bottom part receives a tension and is deformed, the material is easy to flow, the working force can be reduced and the load to the die can be reduced. Since compression is given by the punch 3 and the knockout 7 to the work W1, the work W1 becomes difficult to be broken.
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