Forging method of cross-shaped forge piece

Abstract

The invention relates to the technical field of forging, in particular to a forging method of a cross-shaped forge piece. The method comprises the following steps of: heating a bar, flattening the whole bar, separating and drawing out the bar, putting the drawn section into a first set of special separating tire film, locally upsetting and broadening the exposed head, finally locally drawing out the large head in two directions, keeping the middle part of the large head unchanged, and forging through a second set of special tire film to obtain a cross-shaped intermediate blank, and the bottom of the middle blank is drawn out, a final cross-shaped rough shape is obtained, and the bottom of the middle blank is the section where the materials are drawn out.

Description

Technical Field

[0001] The invention relates to the technical field of forging, and in particular to a forging method for a cross-shaped forging. Background Art

[0002] With the development of aerospace, in recent years, some forgings that need welding and assembly have been gradually replaced by integral forgings with better performance, less raw material loss, larger weight and more complex shapes due to the huge waste of production costs and long production cycle during the assembly process. In order to save costs and improve the utilization rate of raw materials, the rough shape of this type of forgings is also designed to be cross-shaped. The traditional cross-shaped rough shape is formed by integral extrusion or square forging blanks using a large amount of raw materials. The material utilization rate is low and it is only suitable for forgings with smaller size and weight. For large forgings, the traditional billet making method will cause great waste of raw materials. At the same time, due to the overall forging, there are also high requirements for forging equipment. The billet making is difficult, and it is difficult to ensure that the cross is perpendicular to each other. The vertical position of the cross is prone to folding and pinching problems. For large forgings, the use of different tooling for billet making can effectively reduce the size control problems caused by manual operation, improve the consistency and stability of the size of the produced billet, reduce the number of forgings, and improve production efficiency. In the billet making process, by using the designed special tire membranes with different functions, various problems caused by traditional billet making can be effectively solved. Summary of the invention

[0003] The technical problem to be solved by the present invention is: a method for making a cross-shaped forging. The method solves the problems of the difficulty of making a traditional free forging blank, the bending, folding, skewing and the like during the blank making process leading to the scrapping of the blank, reduces the number of forging fires, improves production efficiency, reduces energy consumption, improves the utilization rate of raw materials, and reduces production costs.

[0004] The technical solution of the present invention is:

[0005] A forging method for a cross-shaped forging is provided, comprising:

[0006] After the bar is heated, it is flattened as a whole, divided and stretched, and the stretched section is placed in the first set of special dividing membranes. The exposed head is partially upset and widened, and finally the big head is partially stretched in two directions. The middle part of the big head remains unchanged, and then it is forged with the second set of special membranes to obtain a cross-shaped intermediate billet. The bottom of the intermediate billet is stretched to obtain the final cross-shaped rough shape, and the bottom of the intermediate billet is the section that is divided and stretched.

[0007] Furthermore, the mold cavity of the first set of special material dividing fetal membranes is a rectangular groove.

[0008] Furthermore, the mold cavity of the second set of special fetal membranes is a T-shaped groove, and the T-shaped groove is used to form the locally elongated head areas on both sides.

[0009] Furthermore, the preparation of the first set of forging blanks requires repeated entry and exit of the dividing membrane for local upsetting and bidirectional stretching operations until the size reaches the designed size.

[0010] Furthermore, after the bidirectional local elongation, the method further comprises: shaping the middle part of the large head.

[0011] Furthermore, before forging the membrane, the membrane needs to be heated to 300±50°C.

[0012] Furthermore, before the fetal membrane is forged, the second dedicated fetal membrane needs to be heated to 300±50°C.

[0013] The beneficial effects are:

[0014] By adding different membranes during the forging process, the problem of difficult billet making in traditional free forging and billet scrapping caused by bending, folding, skewing, etc. during the billet making process is solved. At the same time, the forging times are reduced, production efficiency is improved, energy consumption is reduced, raw material utilization is improved, and production costs are reduced. The method is suitable for the manufacturing of cross-shaped billets for various large cross-shaped forgings. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Flow chart of the forging method.

[0016] Figure 2 This is a schematic diagram of the structure of the first set of special material-dividing tire molds.

[0017] Figure 3 This is a schematic diagram of the structure of the second set of special tire molds. DETAILED DESCRIPTION

[0018] The present invention provides a forging method for a cross-shaped forging, comprising:

[0019] After heating, the bar is flattened as a whole, divided and stretched, and placed in the first set of special dividing molds. The head exposed outside the dividing mold is partially upset, then widened, and finally the two sides of the big head are stretched, and then a cross-shaped forging blank is obtained after shaping;

[0020] After heating, the head area on both sides after elongation is partially closed-die forged through the second set of special tire membranes, so that the head of the forging blank is partially formed;

[0021] Remove the blank from the fetal membrane, and lengthen the bottom to obtain the final cross-shaped rough shape;

[0022] like Figure 2 As shown, the cavity of the first set of tire membranes is rectangular, and the volume of the cavity is the same as the bottom volume of the T-shaped blank after drawing and dividing, and the height is greater than the height of the bottom of the blank, so as to facilitate local upsetting and drawing of the head of the T-shaped blank exposed outside the first set of tire molds.

[0023] like Figure 3 As shown, the mold cavity of the second set of special tire membranes is divided into two parts, the lower part of the mold cavity is the same shape as the material division mold, and the upper part of the mold cavity is the same size as the required blank, which is used for the final shaping of the head after local upsetting and elongation.

[0024] The preparation of the first set of membrane forging blanks requires repeated entry and exit of the dividing membrane for local upsetting and bidirectional stretching operations until the size reaches the designed size.

[0025] This embodiment is a forging of a hook beam mounting bracket of a certain type of aircraft. The shape of the forging is cross-shaped, the shape of the forging is complex, and the cross-sectional area varies greatly. The material is AF1410 high-strength steel, the size of the enclosure is 1288㎜×1072㎜×108㎜, and the projection area of ​​the forging is 0.44m 2 .like Figure 1 As shown, the forging method includes:

[0026] In the first fire of billet making, the bar is first heated to 900℃ and kept warm for 150min, then heated to 1080℃ and kept warm for 120min. After being taken out of the furnace, a 1600T hydraulic press is used to flatten the bar as a whole, divide it into sections and stretch it, and then air-cool it to room temperature.

[0027] For the second batch of billet making, the billet is first heated to 900℃ and kept warm for 100min, then heated to 1080℃ and kept warm for 75min. A 1600T hydraulic press is used to locally upset the billet with the first set of special tire membrane, and then air-cooled to room temperature.

[0028] For the third fire of billet making, the billet forged in the second fire is first heated to 900℃ and kept warm for 100min, then heated to 1080℃ and kept warm for 75min. A 1600T hydraulic press is used with the first set of special tire membranes to continue to locally upset the billet and widen the two wings of the cross, and then air-cooled to room temperature.

[0029] For the fourth fire of billet making, the billet forged in the third fire is first heated to 900℃ and kept warm for 75 minutes, then heated to 1080℃ and kept warm for 60 minutes, and a 1600T hydraulic press is used to forge the two wings of the cross-shaped billet with the second set of special tire membrane to the final required size, and then the billet is taken out of the tire membrane to stretch the cross-shaped bottom to obtain the final billet, which is then air-cooled to room temperature.

[0030] Through the above forging process, the size of the cross-shaped billet is basically controlled by the fetal membrane, which greatly reduces the impact of manual operation, improves production efficiency, and the raw material utilization rate is as high as 92%; and ensures the stability and controllability of the product during batch production of forgings.

Claims

1. A forging method for a cross-shaped forging, characterized in that: include: After the bar is heated, it is flattened as a whole, divided and stretched, and the stretched section is placed in the first set of special dividing membranes. The exposed head is partially upset and widened, and finally the big head is partially stretched in two directions. The middle part of the big head remains unchanged, and then it is forged with the second set of special membranes to obtain a cross-shaped intermediate billet. The bottom of the intermediate billet is stretched to obtain the final cross-shaped rough shape, and the bottom of the intermediate billet is the section that is divided and stretched.

2. The method according to claim 1, characterized in that The first set of special material dividing membranes has a cavity that is a rectangular groove.

3. The method according to claim 1, characterized in that The second set of special fetal membranes has a T-shaped slot as the cavity, which is used to form the partially elongated head areas on both sides.

4. The method according to claim 1, characterized in that: The preparation of the first set of membrane forging blanks requires repeated entry and exit of the dividing membrane for local upsetting and bidirectional stretching operations until the size reaches the designed size.

5. The method according to claim 1, characterized in that After the bidirectional local elongation, the method further comprises: shaping the middle part of the large head.

6. The method according to claim 1, characterized in that Before forging the membrane, the membrane needs to be heated to 300±50℃.

7. The method according to claim 1, characterized in that Before forging the fetal membrane, the second special fetal membrane needs to be heated to 300±50℃.

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