JPH06339743A - Die forging method for hard-to-work material - Google Patents

Abstract

PURPOSE:To provide a die forging method which can easily make bugle-like hollow products by using a hard-to-work material of titanium alloy, etc. CONSTITUTION:In a die forging method of a hard-to-work material, a punch 25 is pressed into a hole 11 of a hollow bar-like hard-to-work material 10 worked with hole penetrating and die forging is executed. In this case, the thickness is preliminarily worked on the end part of the hollow bar-like hard-to- work material 10 that the hole is penetrated so as not to close the hole 11, in succession, a pressing punch 25 is pressed into the hole 11 and the die forging is preferably executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forging method of a difficult-to-machine material for producing a trumpet-shaped hollow forged product.

[0002]

2. Description of the Related Art Conventionally, when manufacturing a trumpet-shaped hollow product using a difficult-to-machine material such as a superalloy or a titanium alloy, a solid stepped bar-shaped forged material is machined to produce a product having a predetermined shape. is doing. However, mechanically working a solid stepped rod-shaped forged material to a predetermined shape has a problem that it is extremely time-consuming and costly. For the purpose of improving this point, the present inventor has tried to press the indenting punch into one end of the rod-shaped difficult-to-machine material by die-in forging, and then machine the inside. FIG. 4 illustrates the case of the die forging. In the figure, 40 is a difficult-to-process material,
It is placed in a die composed of a lower die 41 and an upper die 42, and a pushing punch 44 having a convex portion 43 at one end thereof is pushed in to form a forged product having a predetermined shape.

[0003]

In the case of the die-insertion forging method described above, the pushing of the pushing punch has a limit.
In other words, there is a problem that the forging machine has a limited capacity for the indenting punch, so that it is possible to obtain only one with a certain indentation depth. Increasing the depth created a new problem of cracking at the edges.
Therefore, it is desired to develop a method for obtaining a trumpet-shaped hollow forged product more easily. The present invention has been made in view of the above circumstances. Therefore, an object of the present invention is to provide a mold forging method capable of easily producing a trumpet-like hollow forged product using a difficult-to-machine material such as a titanium alloy.

[0004]

Means and Actions for Solving the Problems
As a result of the study, it was found that the above object can be achieved by using a bar-shaped difficult-to-machine material in the form of a hollow pipe to complete the present invention. That is, the method of die forging of a difficult-to-machine material of the present invention is characterized in that a die punch is pushed into a hole of a hollow rod-shaped difficult-to-machine material and a die punch forging is performed. In the method of mold forging of the difficult-to-machine material of the present invention, at the end of the hollow-bar-shaped difficult-to-machine material that has been subjected to hole forming, a thick-walled portion is formed by performing upsetting so as not to close the hole, and then the above It is preferable to adopt a method in which a pressing punch is pressed into the hole to perform forging forging. In this case, the pushing punch will not be misaligned, and
Deformation does not occur in the forged part.

[0005]

The present invention will be described in detail below with reference to the drawings. In the present invention, first, a hollow body is produced by making a hole in a bar-shaped difficult-to-machine material such as a superalloy or a titanium alloy. FIG. 1 is a cross-sectional view of a hollow bar-shaped difficult-to-work material to be forged, and a hollow bar-shaped difficult-to-work material 10 has a hole 11 penetrating the center thereof. In addition, in FIG. 1, a hole that penetrates the bar-shaped difficult-to-machine material is provided, but this hole does not necessarily have to penetrate.

Next, the hollow rod-shaped difficult-to-work material is subjected to mold forging, and FIG. 2 illustrates the state. As a forging device, a lower mold 21 having an annular convex portion 22 in the center, an upper mold 23 fitted with the lower mold 21 and a convex shape having a shape matching the predetermined inner shape, as a forging device. A punch having a portion 24 and movable in the vertical direction is used. After the hollow rod-shaped difficult-to-work material 10 is placed on the die including the lower mold 21 and the upper mold 23 of the mold forging device, the punch 25 is lowered from the upper part so that the convex portion 24 becomes the hollow-bar-shaped difficult-to-work material. Hole 11
And forged into a predetermined shape.

In the present invention, prior to performing the above-mentioned forging operation, the hollow bar-shaped difficult-to-machine material which has been subjected to the hole processing is previously subjected to upsetting so as not to close the hole at the end thereof, and the thick portion Are preferably formed. FIG. 3 is for explaining the case. As a forging device used in this case, a lower mold 31 having a shape corresponding to the thick portion formed at the end of the hollow rod-shaped difficult-to-machine material and having an annular convex portion 32 in the center, and an upper mold fitted with the lower mold 31. 33 and a convex portion 34 having a size substantially equal to the size of the hole of the hollow rod-shaped difficult-to-machine material,
It is composed of a punch 35 that can move in the vertical direction. Also in this case, the hollow bar-shaped difficult-to-work material 10 is
The die forging device is placed on the die including the upper die 33 and the lower die 31, and the punch 35 is lowered from the upper portion. In this case, since the convex portion 34 has almost the same size as the hole 11 of the hollow rod-shaped difficult-to-machine material, when the convex portion 34 is inserted into the hole 11 of the hollow rod-shaped difficult-to-machine material, the hole is formed by the convex portion 34. It becomes blocked. Therefore, since the upper end portion is upset in that state, the hole in the upper end portion is not crushed and a thick portion protruding in the circumferential direction is formed. The hollow rod-shaped difficult-to-machine material having a thick portion formed at the end formed by this step is then forged by the mold forging device shown in FIG. In this case, since the thick portion formed at the upper end engages with the die, misalignment does not occur. Therefore, the convex portion 24 of the push-in portion punch is smoothly inserted into the hole 11. In addition, since the material of the thick portion is smoothly forged during forging, there is an advantage that defects such as deformation and cracks do not occur at the ends.

[0008]

EFFECTS OF THE INVENTION Since the present invention has the above-mentioned structure, a trumpet-shaped hollow forged product having a predetermined shape can be produced extremely easily as compared with the conventional machining of a stepped rod-shaped forged material. can do. Further, since the indentation depth of the indenting punch in the case of the die forging is drastically increased as compared with the case of the die forging as shown in FIG. Does not occur.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a hollow rod-shaped difficult-to-machine material to be forged.

FIG. 2 is an explanatory diagram for explaining the mold-insertion forging of the present invention.

FIG. 3 is an explanatory diagram for explaining the first step of the preferred embodiment of the present invention.

FIG. 4 is an explanatory diagram for explaining a die-insertion forging for comparison.

[Explanation of symbols]

 10 ... Hollow rod-shaped difficult-to-process material 11 ... Hole 21 ... Lower mold 23 ... Upper mold 24 ... Projected part 25 ... Punch 31 ... Lower mold 33 ... Upper mold 34 ... Projected part 35 ... Punch 40 ... Difficult-to-process material 41 ... Lower Mold 42 ... Upper mold 43 ... Convex portion 44 ... Punch.

Claims (2)

[Claims] 1. A method of forging and forging a difficult-to-machine material, characterized in that a pressing punch is pushed into a hole of a hollow-bar-shaped and hard-to-machine material that has been machined to carry out forging and forging. 2. A hollow rod-shaped difficult-to-machine material that has been subjected to hole processing is upset so as not to close the hole to form a thick portion, and then a press punch is pushed into the hole to insert a mold. A forging method for a difficult-to-process material characterized by performing forging.