JPS6233039A - Forging method for discoid forging - Google Patents

Abstract

PURPOSE:To reduce the die expense, and to improve the yield by fixing the center of rod-shaped upper and lower dies by a mandrel, also inserting a work between them, and subsequently, rotating the work or the die and executing the forming successively. CONSTITUTION:A perforated discoid work 2 is manufactured in advance by a free forging method, and set to a lower die 3 through a mandrel 5. Rod-shaped upper die 1 and lower die 3 are formed by aligning its lower face and upper face with a sectional shape of a product, respectively. The upper die 1 is inserted into the mandrel 5 and installed onto the work 2, and thereafter, the upper face of the die 1 is brought to a pressure forming by a press of a simple type or a hammer. At every pressure of once, the dies 1, 3 or the work 2 is rotated a little centering around the mandrel 5 and forging is repeated successively in the peripheral direction. In this way, the die expense is reduced, and also the yield can be improved remarkably by comparing with a free forging.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a forging method for disc-shaped forged products, particularly for disc-shaped forged products with a complicated shape that has a hole in the center and has a carved end face. Regarding forging.

[Background of the invention]

Conventionally, disc-shaped forged products with carved end faces, such as gas turbine discs, are manufactured either by free forging into a disc shape with a rectangular cross section with the carved parts buried, or by die forging using a completely constrained die. It has been.

In the former case, there were many problems in terms of yield, and in the latter case, there were many problems in terms of mold costs and the need for large-capacity presses and hammers.

[Purpose of the invention]

An object of the present invention is to provide a method for precisely forging a disc-shaped forged product having a groove into a shape close to the product shape using a simple die with a press that does not have a large capacity as a die forging press.

(Summary of the invention) A simple mold for achieving the above object is a rod-shaped mold with both the upper mold and the lower mold processed into the desired cross-sectional shape, and the upper and lower molds are joined by a core metal in the center. Sanctuary is a method in which a roughly forged disc-shaped workpiece with a central hole is inserted between a die and a lower die, and the workpiece is sequentially rotated around a core metal while being formed.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings. The simple type is the upper type 1. Lower mold 2. Spring 4. It is composed of a core metal 5.

A workpiece 2 which has been previously forged into a perforated disc shape by a free forging method is set on a lower mold 3 through a core metal 5. After that, insert the upper mold 1 into the core metal, set the upper mold on the workpiece, and then
Pressure is applied to the upper surface of the upper die using a press or hammer to form the workpiece.

- After each pressurization, the die or workpiece is slightly rotated around the core metal and forged in the circumferential direction, and the end face is formed to complete the forging.

Since this method is forging using a partial die, it does not require much pressure and has the advantage that an end face shape close to that of a conventional fully constrained die can be obtained.

〔Effect of the invention〕

According to the present invention, it is possible to forge a disc-shaped forging 4 with a complicated shape, the end face of which is carved using a very simple die, and has the following effects.

1) Yield is significantly improved compared to manufacturing by free forging.

2) Compared to conventional fully constrained die forging, die costs can be reduced, and large-capacity presses, hammers, etc. are not required since it is a partial die.

[Brief explanation of drawings]

Fig. 1 is a plan view showing the implementation status of the present invention, Fig. 2 is A-
It is an A sectional view. 1... Upper die, 2... Material (work), 3... Lower die, 4... Spring, 5... Core metal.

Claims (1)

[Claims] 1. For forging disc-shaped forged products with grooves such as gas turbine discs, which have a center hole and whose end faces are rotationally symmetrical, a rod-shaped upper mold whose upper and lower surfaces have the cross-sectional shape of the product is used. A forging method for a disc-shaped forged product, which is characterized by fixing the center of a lower mold with a core metal, inserting a workpiece between them, and forming the end face shape of the disc into an arbitrary shape while sequentially rotating the workpiece or the mold. .