Abstract: A molten residual layer formed on a surface 26 of an electric-discharge machined portion 12 of a metal molding member 1 is eliminated by using a tool 70 made by a wire discharge grinding method. According to the wire discharge grinding method, a minute tool which is high in processing accuracy and high in hardness can be obtained. Since the molten residual layer formed on a surface 26 of the portion 12 due to the electric-discharge machining is eliminated by using the tool, the molten residual layer can be eliminated uniformly with high accuracy.

Abstract: A molten residual layer formed on a surface 26 of an electric-discharge machined portion 12 of a metal molding member 1 is eliminated by using a tool 70 made by a wire discharge grinding method. According to the wire discharge grinding method, a minute tool which high in processing accuracy and high in hardness can be obtained. Since the molten residual layer formed on a surface 26 of the portion 12 due to the electric-discharge machining is eliminated by using the tool, the molten residual layer can be eliminated uniformly with high accuracy.

Abstract: A forging method for upsetting end portions of a raw material as diameter expansion scheduled portions includes: providing an upsetting apparatus having a fixing die, guides each having an insertion passage for inserting and holding an end portion of the raw material in a buckling preventing state, and punches each for axially pressing the end portion of the raw material inserted in and held by the insertion passage; inserting end portions of the raw material with the end portions protruded from the fixing die into the insertion passages; and moving the guides in direction opposite to moving direction of the punches such that length of exposed portion of the raw material becomes equal to or less than buckling limit length at cross-sectional area of the exposed portion of the raw material while simultaneously axially pressing the end portions of the raw material with the punches.

Abstract: An axial intermediate portion of raw material is held with a holding die in a state in which the intermediate portion is prevented from being enlarged in diameter. The axial end portions of the raw material is inserted in forming dented portions formed at axial end portions of the holding die. The scheduled diameter-enlarging portions are inserted in insertion passages formed in guides. Then, the scheduled diameter-enlarging portions are simultaneously pressed with punches to fill the material of the scheduled diameter-enlarging portions in corresponding forming dented portion while moving each guide in a direction opposite to a moving direction of each punch, thereby enlarging each scheduled diameter-enlarging portion.

Abstract: The invention is directed to a aluminum pipe production method comprising an extrusion step for obtaining an aluminum raw pipe (10) and a drawing step for executing a drawing process of the aluminum raw pipe (10). Before executing the drawing step a slug removing step for removing aluminum slugs (1) adhering to a surface of the aluminum raw pipe (10) is executed by rubbing off the aluminum slugs (1). This can provide an aluminum pipe production method capable of preventing generation of defect protrusions while improving the productivity.

Abstract: A forging method for upsetting end portions of a raw material as diameter expansion scheduled portions includes: providing an upsetting apparatus having a fixing die, guides each having an insertion passage for inserting and holding an end portion of the raw material in a buckling preventing state, and punches each for axially pressing the end portion of the raw material inserted in and held by the insertion passage; inserting end portions of the raw material with the end portions protruded from the fixing die into the insertion passages; and moving the guides in direction opposite to moving direction of the punches such that length of exposed portion of the raw material becomes equal to or less than buckling limit length at cross-sectional area of the exposed portion of the raw material while simultaneously axially pressing the end portions of the raw material with the punches.

Abstract: A forging apparatus 1A includes a swaging apparatus 2 equipped with a fixing die 10, a guide 20 having an insertion passage 22 for inserting and holding a bar-shaped raw material 5 in a buckling preventing state, and a punch 30. The raw material 5 is fixed to the fixing die 10 with the one end portion of the raw material protruded. The one end portion of the raw material 5 is inserted into the insertion passage 22 of the guide 20. Thereafter, while pressing the raw material 5 with the punch 30 in the axial direction, in a state in which an entire peripheral surface of the exposed portion 8 of the raw material 5 exposed between the guide 20 and the fixing die 10 is not restrained, the guide 20 is moved in a direction opposite to the moving direction of the punch 30 so that a length of the exposed portion 8 of the raw material 5 becomes a budding limit length or less at a cross-sectional area of the exposed portion 8 of the raw material 5.

Abstract: The invention is directed to a aluminum pipe production method comprising an extrusion step for obtaining an aluminum raw pipe (10) and a drawing step for executing a drawing process of the aluminum raw pipe (10). Before executing the drawing step a slug removing step for removing aluminum slugs (1) adhering to a surface of the aluminum raw pipe (10) is executed by rubbing off the aluminum slugs (1). This can provide an aluminum pipe production method capable of preventing generation of defect protrusions while improving the productivity.

Abstract: A forging apparatus 1A includes a swaging apparatus 2 equipped with a fixing die 10, a guide 20 having an insertion passage 22 for inserting and holding a bar-shaped raw material 5 in a buckling preventing state, and a punch 30. The raw material 5 is fixed to the fixing die 10 with the one end portion of the raw material protruded. The one end portion of the raw material 5 is inserted into the insertion passage 22 of the guide 20. Thereafter, while pressing the raw material 5 with the punch 30 in the axial direction, in a state in which an entire peripheral surface of the exposed portion 8 of the raw material 5 exposed between the guide 20 and the fixing die 10 is not restrained, the guide 20 is moved in a direction opposite to the moving direction of the punch 30 so that a length of the exposed portion 8 of the raw material 5 becomes a buckling limit length or less at a cross-sectional area of the exposed portion 8 of the raw material 5.

Abstract: An axial intermediate portion of raw material is held with a holding die in a state in which the intermediate portion is prevented from being enlarged in diameter. The axial end portions of the raw material is inserted in forming dented portions formed at axial end portions of the holding die. The scheduled diameter-enlarging portions are inserted in insertion passages formed in guides. Then, the scheduled diameter-enlarging portions are simultaneously pressed with punches to fill the material of the scheduled diameter-enlarging portions in corresponding forming dented portion while moving each guide in a direction opposite to a moving direction of each punch, thereby enlarging each scheduled diameter-enlarging portion.

Abstract: A molten residual layer formed on a surface 26 of an electric-discharge machined portion 12 of a metal molding member 1 is eliminated by using a tool 70 made by a wire discharge grinding method. According to the wire discharge grinding method, a minute tool which high in processing accuracy and high in hardness can be obtained. Since the molten residual layer formed on a surface 26 of the portion 12 due to the electric-discharge machining is eliminated by using the tool, the molten residual layer can be eliminated uniformly with high accuracy.