PURPOSE: To execute upsetting in the forming space of a cylindrical die and to prevent the generation of a flash by providing the cylindrical die which can be freely attached into and detached from the recess of a grip die, a punch to be inserted into the molding space of the cylindrical die, a means for pushing the cylindrical die and a means for pulling said dies to a die for upsetting.

CONSTITUTION: The grip dies 2, 3 are closed and a material 13 is grasped by liners 13. The cylindrical die 1 mounted to the punch 6 is advanced in an arrow X direction. The die 1 is thereby advanced in the recess 4 until a front end face 16 contacts with the base 4a of the recess 4 and is pressed to the base 4a by a compression spring 12. The punch 6 advances further to compress and work the material 14 in the forming space 5 of the die 1. A molded article 17 is thus formed. The collar part 7 of the punch 6 engages with the inside surface at the rear end 8 of the die 1 and the die 1 is pulled from the article 17 when the punch 6 is thereafter retreated. The article 17 is therefore taken out by opening the movable grip die 3.