Combined die for deep cylindrical forgings

Abstract

The utility model relates to the technical field of forging, in particular to a combined die for a deep cylindrical forge piece. The combined die comprises an upper die and a lower die, the upper die comprises an upper die base body and a punch; a step blind hole with large outside and small inside is formed in the working surface of the upper die base body, the step bottom surface serves as a strike-bearing surface, and the large circular section side wall serves as an upper and lower die guide lock catch; the small round section is used for mounting a punch; and the punch, the large round section and the lower die define a cavity of the deep cylindrical forge piece.

Description

Technical Field

[0001] The utility model relates to the technical field of forging, in particular to a combined die for deep cylindrical forgings. Background Technique

[0002] A certain type of superalloy forging, the forging material is GH4169, the forging structure is a rotating body with a deep blind hole, the outer shape is approximately frustum-shaped, the outer contour diameter of the forging is 498, and the height is 420 frustum, and the upper surface has a blind hole with a depth of 260. The forming process of such forgings is usually as follows: the bar stock is upset, and it is formed by multi-pass die forging on a die forging equipment, and the die forging equipment is a hydraulic press. During the die forging process, a lower die with a deep cavity and an upper die with a punch are required as Figure 1 shown. The size of the upper die punch is determined according to the size of the blind hole of the forging, and the size of the lower die is designed according to the outer shape of the forging. Since the depth of the blind hole of the deep cylindrical forging is large and the diameter is small, the height-diameter ratio of the die punch is relatively large. Forging dies generally use hot work die steel. Due to the large deformation resistance and narrow process window of superalloys, it has always been a major problem in forging technology.

[0003] During the die forging process, due to the slow pressing speed during forging by the hydraulic press, the contact time between the forging die and the blank is long, the temperature of the blank is high, and the deformation resistance of the superalloy is large. The upper die punch contacts and transfers heat with the blank, quickly raises the temperature, and at the same time under the action of the deformation resistance of the forging, the punch often piles up and deforms, and even scrapped. The service life of the punch is short, resulting in an increase in the production cycle and a significant increase in production costs. And sometimes, due to the deformation of the punch, it is difficult to demold the forging from the upper die, resulting in the scrapping of the forging. It is difficult to mass-produce forgings. Content of the Utility Model

[0004] The purpose of the utility model is: to reduce the production cost of forgings, improve the qualified rate of forgings, avoid the scrapping of forgings caused by the forging punching the punch due to the punch piling up; improve the service life of the forging die punch, shorten the die repair and manufacturing cycle, reduce the die repair and manufacturing cost, shorten the production cycle of forgings, and thus improve the production efficiency of forgings.

[0005] Technical Solution:

[0006] Provide a combined die for deep cylindrical forgings, including: an upper die and a lower die;

[0007] The upper die includes an upper die base body and a punch;

[0008] A stepped blind hole with a large outer and a small inner is opened on the working surface of the upper die base body. The bottom surface of the step serves as the impact-bearing surface, and the side wall of the large circular section serves as the upper and lower die guiding and locking buckle; the small circular section is used to install the punch;

[0009] The punch, the large circular section, and the lower die enclose the cavity of the deep cylindrical forging.

[0010] Further, a through hole is formed in the upper die base along its chordal direction, and a middle part of the through hole wall is cut off by a small circular segment; a groove is formed on the side surface of the cylindrical tail cake end of the punch; the groove cooperates with the cut-off part of the through hole wall, and the groove and the through hole form a complete through hole;

[0011] The upper die further includes a wedge block; the wedge block penetrates into the through hole, and a part of the wedge block exposed in the middle of the through hole is wrapped by the groove.

[0012] Further, a small through hole is formed upward from the center of the bottom surface of the stepped blind hole for ejecting the punch.

[0013] Further, the punch is of a rotary body structure.

[0014] Further, the wedge block is of a long rod structure with a rectangular or circular cross section.

[0015] Further, the cross section of the wedge block along its length direction is trapezoidal, and the base angle of the trapezoid is 89.5°.

[0016] Further, the upper die base is a hot work die steel base, and the punch is a superalloy punch.

[0017] The beneficial effects are as follows: By using a combined structure upper die for die forging on the basis of the original forging method, post-forging cooling method and heat treatment method, the service life of the forging die punch is greatly improved, the production cost of the forging is reduced, the forging is prevented from being scrapped due to the forging wrapping the punch caused by the punch piling up, and the qualified rate of the forging is improved; and the production consumption caused by die repair and die manufacturing is shortened, the die repair and die manufacturing costs are reduced, the production cycle of the forging is shortened, thereby improving the production efficiency of the forging. It provides an alternative way for the stable and batch production of deep cylindrical forgings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the original forging die.

[0019] Figure 2 It is a schematic diagram of the upper die component of the forging die described in the present invention.

[0020] Figure 3a It is a schematic sectional view of the forging die used in the embodiment.

[0021] Figure 3b It is a bottom view of the upper die used in the embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The present utility model provides a combined die device for deep cylindrical forgings, as shown in Figure 2 , 3a , 3b, including: an upper die 1 and a lower die 2;

[0023] The upper die 1 is composed of an upper die base body 4, a punch 5 and a wedge block 6; among them, the upper die base body 1 is cylindrical, with a small through hole 41 and a large blind hole 42 in the middle. There is a groove at a certain position on the side wall of the large blind hole 41 from the bottom. The 43a and 43b surfaces of the groove are parallel to each other, and the groove surface 43c is a slope with an angle of 0.5° along the length direction.

[0024] The punch 5 is detachable. The punch 5 is provided with a cylindrical tail cake 51, and the cylindrical tail cake 51 can be embedded in the large blind hole 42 of the upper die base body 4. There is a groove 52 in the middle section of the cylindrical tail cake 51 of the punch 5.

[0025] The wedge block 6 is placed between the upper die base body 4 and the punch 5 and is fitted with the groove 43 of the upper die base body 4 and the groove 52 of the punch 6.

[0026] The structure of the wedge block 6 is a long rod shape, and the cross section is circular or rectangular. The wedge block 6 is provided with a slope 61 with an angle of 0.5° along the length direction.

[0027] The upper die base body 4 is made of ordinary medium-temperature hot work die steel.

[0028] The punch 5 is made of superalloy.

[0029] The wedge block 6 is made of ordinary medium-temperature hot work die steel.

[0030] Example 1:

[0031] This example is a drum shaft forging for a certain type of aircraft engine. The material is GH4169G superalloy. The shape of the forging is a deep cylinder type, and the outer shape is approximately frustum-shaped. The outer contour diameter of the forging is 498, and the height is 420 frustum. There is a blind hole with a depth of 260 on the upper surface.

[0032] The mold is divided into an upper die 1 ( Figure 2 ), and a lower die 2. The upper die base body 4 is a cylindrical structure, with a diameter of 1000 mm and a height of 480 mm; there are a small through hole and a large blind hole in the middle of the upper die base body 4. The diameter of the small through hole is 150 mm; the diameter D of the large blind hole is 480 mm, and the depth H1 is 150 mm. There is a groove running through the entire upper die base body 4 at a certain position on the side wall of the large blind hole from the bottom. The groove is 38 mm away from the bottom surface of the large blind hole, the groove depth is 35 mm, and the width a is 60 mm;

[0033] The punch 5 is detachable. The punch 5 is a rotating body structure. The punch tail is provided with a cylindrical tail cake with a diameter of 500 mm, and the height of the tail cake is 150 mm. The cylindrical tail cake can be embedded in the large blind hole of the upper die base body 4. There is a groove on the side surface of the middle section of the cylindrical tail cake of the punch 5, the groove depth is 28 mm, and the groove is 35 mm away from the bottom surface of the punch.

[0034] The wedge block 6 is a long rod structure with a rectangular cross-section, having a cross-sectional height of 60 mm and a width of 55 mm; the side surface 61 of the wedge block 6 is an inclined surface with a slope of 0.5° along the length direction.

[0035] The wedge block 6 is placed between the upper die base 4 and the punch 5 and is fitted with the grooves of the upper die base 4 and the punch 5.

[0036] The raw material of the upper die base 4 is 5CrNiMo, the raw material of the punch 5 is GH761 (GH2132), and the raw material of the wedge block 6 is 5CrNiMo.

[0037] For die forging, first heat the forging blank to the forging temperature and hold for a certain time, then use a manipulator to place the forging blank into the installed die cavity, and then perform forging, with a pressing speed of 5 mm / s. After forging, the forgings are cooled and subjected to dimensional inspection.

[0038] Based on the original forging method, post-forging cooling method and heat treatment method, by adopting a combined structure upper die for die forging, the service life of the forging die punch has been greatly improved. At present, 34 forgings have been produced by the die, reducing the production cost of the forgings, avoiding the scrapping of the forgings caused by the punch being wrapped by the forgings due to the punch piling up, and improving the qualification rate of the forgings; and shortening the production consumption caused by die repair and die manufacturing, reducing the die repair and die manufacturing costs, and shortening the production cycle of the forgings; and ensuring the stability and controllability of the products during batch production of the forgings.

Claims

1. A combined die for deep cylindrical forgings, characterized in that Including: Upper die and lower die; The upper die includes an upper die base body and a punch; A stepped blind hole with a large outer and small inner diameter is opened on the working surface of the upper die base body. The bottom surface of the step serves as the impact-bearing surface, and the side wall of the large circular section serves as the guiding and locking buckle for the upper and lower dies; the small circular section is used to install the punch; The punch, the large circular section, and the lower die enclose the cavity of the deep cylindrical forging.

2. The combined mold according to claim 1, characterized in that A through hole is opened along the chord direction of the upper die base body, and the middle part of the through hole wall is cut off by the small circular section; a groove is opened on the side surface of the cylindrical tail cake end of the punch; the groove cooperates with the cut-off part of the through hole wall, and the groove and the through hole form a complete through hole; The upper die further includes a wedge block; the wedge block penetrates into the through hole, and the exposed part of the wedge block in the middle of the through hole is wrapped by the groove.

3. The combined mold according to claim 1, characterized in that A small through hole is opened upward at the center of the bottom surface of the stepped blind hole for ejecting the punch.

4. The combined mold according to claim 1, characterized in that, The punch is of a rotating body structure.

5. The combined mold according to claim 1, characterized in that, The wedge block is of a long rod structure with a rectangular or circular cross-section.

6. The combined mold according to claim 5, characterized in that, The cross-section of the wedge block along the length direction is trapezoidal, and the base angle of the trapezoid is 89.5°.

7. The combined mold according to claim 1, wherein The upper die base body is a hot work die steel base body, and the punch is a superalloy punch.

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