A method for material forming, by means of a movable impact head and tool combination and a drive unit, the method including moving the drive unit to provide kinetic energy to the impact head and tool combination, for the impact head and tool combination to strike a work material, so as to form the work material. A return movement of the movable impact head and tool combination, away from the work material, after the strike of the work material by the impact head and tool combination, is dampened.

In the invention, a joining means having a ram tool, a countertool and a holder with an opening to accommodate the ram tool or the countertool, is described. The two tools are arranged coaxial with each other at different ends of a C-bracket. The holder comprises at least one plane contact surface arranged on the outer surface of the holder, resting in contact with at least one plane face of the corresponding end of the C-bracket and detachably fastened thereto. Between the contact surface and the face, at least one interlay is arranged, determining the information and/or the distance of the contact surface from the face.

In the invention, a joining means having a ram tool, a countertool and a holder with an opening to accommodate the ram tool or the countertool, is described. The two tools are arranged coaxial with each other at different ends of a C-bracket. The holder comprises at least one plane contact surface arranged on the outer surface of the holder, resting in contact with at least one plane face of the corresponding end of the C-bracket and detachably fastened thereto. Between the contact surface and the face, at least one interlay is arranged, determining the information and/or the distance of the contact surface from the face.

A forging die device is configured in such a manner that die heating heater plates 11, 21 are disposed respectively between a die 1 which is held at the outer periphery by die holders 12, 22, and die holding means 14a, 24a composed of heat insulating plates 13, 23 and die plates 14, 24, and the die holders, the die holding means and the die plates are integrated together. After the preheated die 1 is placed on the heated die holding means, the die 1 is heated by heating means, and forming surfaces 10a, 20a of the die are heated to a required temperature immediately before forging.

A forging die device is configured in such a manner that die heating heater plates 11, 21 are disposed respectively between a die 1 which is held at the outer periphery by die holders 12, 22, and die holding means 14a, 24a composed of heat insulating plates 13, 23 and die plates 14, 24, and the die holders, the die holding means and the die plates are integrated together. After the preheated die 1 is placed on the heated die holding means, the die 1 is heated by heating means, and forming surfaces 10a, 20a of the die are heated to a required temperature immediately before forging.

In a crankshaft 200, one hole 213L formed in a crankpin 213 has a bottom surface having a larger area and a depth from a surface of the crankpin less than those of another hole 213M. In forming the hole 213L and the hole 213M, a preformed product 200 of the crankshaft having a shape smaller than that of a cavity is disposed in a die set and punches are simultaneously inserted into the crankpin 213. By this operation, the hole 213L and the hole 213M are simultaneously formed in each crankpin 213 of the preformed product 200.

In a crankshaft 200, one hole 213L formed in a crankpin 213 has a bottom surface having a larger area and a depth from a surface of the crankpin less than those of another hole 213M. In forming the hole 213L and the hole 213M, a preformed product 200 of the crankshaft having a shape smaller than that of a cavity is disposed in a die set and punches are simultaneously inserted into the crankpin 213. By this operation, the hole 213L and the hole 213M are simultaneously formed in each crankpin 213 of the preformed product 200.

Two press dies are formed by arranging a plurality of segments side by side to form die faces. The press dies are used to press a plate member. First and second joint portions are positioned differently between one of the press dies and the other of the press dies.

Two press dies are formed by arranging a plurality of segments side by side to form die faces. The press dies are used to press a plate member. First and second joint portions are positioned differently between one of the press dies and the other of the press dies.

A press die assembly includes a fixed die and a movable die. The fixed die includes a fixed-side forming section that includes a first forming surface, and multiple metal fixed-side support blocks arranged in a planar direction. The fixed-side support blocks support the fixed-side forming section from a side opposite to the first forming surface. The movable die includes a movable-side forming section that includes a second forming surface that faces the first forming surface, and multiple metal movable-side support blocks arranged in the planar direction. The movable-side support blocks support the movable-side forming section from a side opposite to the second forming surface. The Young's moduli of the fixed-side support blocks increase with increasing proximity to a central portion of the first forming surface. The Young's moduli of the movable-side support blocks increase with increasing proximity to a central portion of the second forming surface.