Abstract: Provided is a hot upset forging method enabling high shape precision to be obtained. The hot upset forging method includes inserting a workpiece (1), with a bottom face diameter d and a height h satisfying h/d>3, into an insertion hole provided passing through a mold (2) of a height H disposed on an anvil (4), and increasing the diameter of the workpiece (1) while decreasing the height of the workpiece (1) to form a forged material. The mold satisfies the following relationships (1) to (3). (1) A shape of the insertion hole and the cross-sectional shape of the workpiece are substantially similar shapes. (2) The height h of the workpiece (1)?the height H of the mold (2). (3) A largest diameter dl of the workpiece 1, and the maximum inner diameter D of the insertion hole, in the height range of the workpiece (1), satisfy dl<D?dl×1.5.

Abstract: Provided are a manufacturing method for a blade material and a manufacturing device for a blade material, by which a long blade material can be manufactured without using a large-sized press forging machine. A manufacturing method for a blade material, in which hot forging is sequentially performed by molds from the root side to a blade (vane) tip, wherein when a root-side portion is grasped and a material to be forged is restrained by a mold, twisting is performed on a region between the grasped portion and the restrained portion. A manufacturing method for a blade material, in which hot forging and twisting are repeated, is preferable, and a manufacturing method for a blade material, in which hot forging is performed while molds are sequentially changed, is more preferable.

Abstract: Provided is a hot upset forging method enabling high shape precision to be obtained. The hot upset forging method includes inserting a workpiece (1), with a bottom face diameter d and a height h satisfying h/d>3, into an insertion hole provided passing through a mold (2) of a height H disposed on an anvil (4), and increasing the diameter of the workpiece (1) while decreasing the height of the workpiece (1) to form a forged material. The mold satisfies the following relationships (1) to (3). (1) A shape of the insertion hole and the cross-sectional shape of the workpiece are substantially similar shapes. (2) The height h of the workpiece (1)?the height H of the mold (2). (3) A largest diameter dl of the workpiece 1, and the maximum inner diameter D of the insertion hole, in the height range of the workpiece (1), satisfy dl<D<dl×1.5.

Abstract: Provided are a manufacturing method for a blade material and a manufacturing device for a blade material, by which a long blade material can be manufactured without using a large-sized press forging machine. A manufacturing method for a blade material, in which hot forging is sequentially performed by molds from the root side to a blade (vane) tip, wherein when a root-side portion is grasped and a material to be forged is restrained by a mold, twisting is performed on a region between the grasped portion and the restrained portion. A manufacturing method for a blade material, in which hot forging and twisting are repeated, is preferable, and a manufacturing method for a blade material, in which hot forging is performed while molds are sequentially changed, is more preferable.