In a die for compressing and sizing a sintered body at straight portions, upper taper portions are provided on a die upper portion and a core rod upper portion, and the straight portions are provided at a die lower portion and a core rod lower portion. The die upper portion and the core rod upper portion have Young's moduluses higher than the die lower portion and the core rod lower portion. The die upper portion and the core rod upper portion are made of materials having Young's moduluses that are at least 50 GPa higher than that of the sintered body. The sintered body can be densified with a smaller ironing margin. Since the sintered body is ironed without being compressed, by the upper taper portions and the core rod upper portion having high Young's moduluses, the die is prevented from breaking and being abraded due to ironing.

In a die for compressing and sizing a sintered body at straight portions, upper taper portions are provided on a die upper portion and a core rod upper portion, and the straight portions are provided at a die lower portion and a core rod lower portion. The die upper portion and the core rod upper portion have Young's moduluses higher than the die lower portion and the core rod lower portion. The die upper portion and the core rod upper portion are made of materials having Young's moduluses that are at least 50 GPa higher than that of the sintered body. The sintered body can be densified with a smaller ironing margin. Since the sintered body is ironed without being compressed, by the upper taper portions and the core rod upper portion having high Young's moduluses, the die is prevented from breaking and being abraded due to ironing.

A mold for molding a case of a mobile device includes a first, second, third, fourth and fifth main body, connection slide blocks, and first and second abutment slide blocks. The connection slide blocks and the second abutment slide blocks are inlaid in first and second slide channels of the first and second main bodies. The first abutment slide blocks are inlaid in channels of the connection slide blocks. The third, fourth and fifth main bodies are horizontally movable relative to the first and second main bodies. The first and second main bodies, the connection slide blocks and the first and second abutment slide blocks together define a male mold section and the third, fourth and fifth main bodies together define a female mold section. A metal thin sheet is placed on the male mold section and pressurized and molded by the female mold section to form the case.

A mold for molding a case of a mobile device includes a first, second, third, fourth and fifth main body, connection slide blocks, and first and second abutment slide blocks. The connection slide blocks and the second abutment slide blocks are inlaid in first and second slide channels of the first and second main bodies. The first abutment slide blocks are inlaid in channels of the connection slide blocks. The third, fourth and fifth main bodies are horizontally movable relative to the first and second main bodies. The first and second main bodies, the connection slide blocks and the first and second abutment slide blocks together define a male mold section and the third, fourth and fifth main bodies together define a female mold section. A metal thin sheet is placed on the male mold section and pressurized and molded by the female mold section to form the case.

The invention relates to a method for producing a cylindrical component, particularly of turbomachines. In the process, a heated blank is provided. The blank is then formed to create a flat blank (2). The flat blank (2) is next bent and/or rolled to form a cylindrical half-shell (40).

The invention relates to a method for producing a cylindrical component, particularly of turbomachines. In the process, a heated blank is provided. The blank is then formed to create a flat blank (2). The flat blank (2) is next bent and/or rolled to form a cylindrical half-shell (40).

A ring molded article manufacturing method capable of reliably and efficiently producing a ring molded article in which dead metal regions are reduced, and a ring material used for producing the ring molded article, are provided. The present invention relates to the method for manufacturing a ring molded article having two convex portions which respectively protrude on both sides of the ring molded article in a direction of a center axis thereof and extend in a direction of a circumference of the ring molded article. In the manufacturing method, the ring material is placed inside two molds on which concave portions respectively corresponding to the convex portions are formed, in a condition in which the ring material is supported by a region on an outer peripheral side from an outer peripheral side corner in the concave portion of one of the two molds and a region on an inner peripheral side from an inner peripheral side corner in the concave portion of another of the two molds, the ring material is then forged so as to be pressed by the two molds in a direction of a center axis of the ring material, and the ring molded article is thus produced. In addition, the present invention relates to the ring material used for producing the ring molded article.

A ring molded article manufacturing method capable of reliably and efficiently producing a ring molded article in which dead metal regions are reduced, and a ring material used for producing the ring molded article, are provided. The present invention relates to the method for manufacturing a ring molded article having two convex portions which respectively protrude on both sides of the ring molded article in a direction of a center axis thereof and extend in a direction of a circumference of the ring molded article. In the manufacturing method, the ring material is placed inside two molds on which concave portions respectively corresponding to the convex portions are formed, in a condition in which the ring material is supported by a region on an outer peripheral side from an outer peripheral side corner in the concave portion of one of the two molds and a region on an inner peripheral side from an inner peripheral side corner in the concave portion of another of the two molds, the ring material is then forged so as to be pressed by the two molds in a direction of a center axis of the ring material, and the ring molded article is thus produced. In addition, the present invention relates to the ring material used for producing the ring molded article.

In a center hole forming method, an object to be processed is inserted in a die hole and a shaft is drawn from the object. A load toward a first axial end surface of the object is applied to a second axial end surface of the object without taking out the object from the die hole. A diameter of the first axial end surface is smaller than a diameter of the second axial end surface. A center hole is formed in the first axial end surface by pressing a counter punch against the first axial end surface in a state that the load is applied to the second axial end surface.

In a center hole forming method, an object to be processed is inserted in a die hole and a shaft is drawn from the object. A load toward a first axial end surface of the object is applied to a second axial end surface of the object without taking out the object from the die hole. A diameter of the first axial end surface is smaller than a diameter of the second axial end surface. A center hole is formed in the first axial end surface by pressing a counter punch against the first axial end surface in a state that the load is applied to the second axial end surface.