A forging design method to prevent the bottom deformation dead zone of large special-shaped barrel forgings

Abstract

The present invention provides a forging design method for preventing deformation dead zones at the bottom of large barrel-shaped forgings. The method comprises: adding a two-step boss structure to the outer area of ​​the flat bottom of the forging; designing a shape-matching lower die or lower ejector die structure corresponding to the bottom of the forging; performing three-dimensional modeling; simulating the large special-shaped barrel forging, adjusting the height and width of the two-step boss structure at the bottom of the forging, and the matching shape and dimensions of the lower die or lower ejector die according to the strain distribution of the large special-shaped barrel forging; and analyzing the streamline distribution of the large special-shaped barrel forging to ensure uniform deformation and smooth streamlines in the area of ​​the part to be processed, and meeting structural and performance requirements. The present invention effectively shifts the deformation dead zones on both sides outward or downward to below the area of ​​the part to be processed. At the same time, the increased deformation at the bottom prevents the possibility of a deformation dead zone in the center area, thereby significantly ensuring uniform strain distribution and smooth and reasonable streamlines in the area of ​​the part to be processed at the bottom of the large special-shaped barrel forging.

Description

Technical Field

[0001] The invention relates to a forging design method and a die for preventing a deformation dead zone at the bottom of a large barrel-shaped forging, belonging to the technical field of forging design. Background Art

[0002] Large-sized special-shaped barrel components are key components in the aviation field. Their maximum dimensions are 600~1500mm, and the barrel wall thickness is 10~100mm. They are large-sized thin-walled components, and their requirements for organization and performance are extremely high and uniform. Figure 1 As shown in the figure, when designing and manufacturing large barrel-shaped forgings by traditional forging methods, the bottom of the barrel-shaped forging is generally designed to be flat; Figure 2 As shown in the figure, there is a large uneven strain distribution and three difficult-to-deform areas or deformation dead zones in the bottom area, which leads to large differences in the microstructure and grain size, large differences in mechanical properties, and uneven streamlines in different areas of the bottom of the forging. As a result, the microstructure and performance of the bottom of the part after processing are greatly different, and the bottom center and two side areas cannot meet the product microstructure and performance requirements.

[0003] Therefore, how to control the uneven strain distribution, eliminate the deformation dead zone in the area of ​​the forging parts to be processed, and obtain reasonable streamlines to ensure that the parts to be processed that meet the organizational performance requirements are technical problems that need to be solved by technical personnel in this field. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a forging design method that prevents deformation dead zones at the bottom of large special-shaped barrel forgings, thereby solving the problems of uneven strain distribution at the bottom of large special-shaped barrel forgings and the existence of deformation dead zones in the area of ​​the forging parts to be processed.

[0005] The invention also provides a forging die designed according to the method for preventing the deformation dead zone at the bottom of a large-scale special-shaped barrel forging.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] A forging design method for preventing a deformation dead zone at the bottom of a large special-shaped barrel forging, characterized by comprising the following steps:

[0008] Step 1: Based on traditional forging design methods, the bottom of a barrel-shaped forging is generally designed to be flat. This design adds a two-step boss structure to the outer area of ​​the flat bottom of the forging.

[0009] Step 2: Based on the first step, shape matching design and 3D modeling are performed on the corresponding lower die or lower ejector die structure at the bottom of the forging;

[0010] Step 3: Based on steps 1 and 2, three-dimensional modeling of the designed forging and corresponding die is performed;

[0011] Step 4: Simulate the large special-shaped barrel forging and adjust the height and width of the two-step boss structure at the bottom of the forging and the matching shape and size of the lower die or lower ejector die according to the strain distribution of the large special-shaped barrel forging;

[0012] Step 5: Analyze the streamline distribution of large special-shaped barrel forgings to ensure that the deformation of the parts to be processed is uniform, the streamlines are smooth, and the organizational performance requirements are met.

[0013] Furthermore, in step 1, this design adds a two-step boss structure to the outer area of ​​the flat bottom of the forging, wherein the width b0 of the flat bottom of the forging is 400~800mm, the design height h1 of the first step is 20~50mm, the single-side width b1 is 50~100mm, the height h2 of the second step platform is 50mm, the single-side width b2 is 50~100mm, and the step draft angle is 15~30°.

[0014] The present invention also provides a die for preventing a deformation dead zone at the bottom of a large barrel-shaped forging obtained by the above method, wherein an ejector die with a lower ejection structure is added to the lower die; the lower die and the ejector die arranged in the middle of the lower die are designed by adjusting the depth dimension of the pit at the bottom of the forging, the thickness dimension of the pit edge, and the matching shape dimension of the lower die or the lower ejector die according to the strain distribution of the large barrel forging; the streamline distribution of the large special-shaped barrel forging is analyzed to ensure that the deformation of the part area to be processed is uniform, the streamline is smooth, and the structural performance requirements are met.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The present invention combines numerical simulation analysis of forgings and optimizes the uneven strain distribution of large special-shaped barrel forgings by changing the height and width dimensions of the boss structure at the bottom of the forging and the matching shape and dimensions of the lower ejection die. This significantly increases the deformation of the deformation dead zone in the center of the bottom, effectively preventing the possibility of a deformation dead zone in the center of the bottom. At the same time, the two deformation dead zones on both sides can be moved outward and downward to below the area of ​​the part to be processed. The strain of the forging is increased by 40%, which is very significant in achieving uniform strain distribution, uniform microstructure and performance, and smooth and reasonable streamlines in the area of ​​the part to be processed at the bottom of the large special-shaped barrel forging.

[0017] 2. The present invention, by designing a two-step boss structure forging and a matching die, can effectively move the deformation dead zones on both sides outward or downward to below the area of ​​the part to be processed; at the same time, the increase in the bottom deformation prevents the possibility of a deformation dead zone in the central area, greatly ensuring that the strain in the area of ​​the part to be processed at the bottom of the large special-shaped barrel forging is evenly distributed and the streamline is smooth and reasonable. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1A typical cross-section (bottom area) of a large barrel forging formed using conventional forming methods is shown;

[0019] Figure 2 The strain distribution diagram of the forging using the traditional forming method;

[0020] Figure 3 A typical cross-sectional view of the large special-shaped barrel forging of the present invention after adding a two-step boss structure;

[0021] Figure 4 To correspond Figure 3 The structure diagram of the lower mold or lower ejector mold cavity;

[0022] Figure 5 This is a strain distribution diagram of a forging obtained by the forging forming method of the present invention;

[0023] Figure 6 This is the streamline distribution diagram obtained by the forging forming method of the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments and drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of protection claimed. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0025] It should be noted that similar reference numerals and letters denote similar items in the following figures. Therefore, once an item is defined in one figure, it does not require further definition or explanation in subsequent figures. In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," and the like indicate positions or locations based on the positions or locations shown in the figures, or the positions or locations in which the invention product is typically placed when in use. These terms are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention. It should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "mounted," "connected," and "connected" should be understood broadly, for example, to mean fixed, detachable, or integral; mechanically connected; directly connected, indirectly connected through an intermediary, or internally connected between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0026] The present invention provides a forging forming method for preventing a deformation dead zone at the bottom of a large barrel-shaped forging, comprising the following steps:

[0027] Step 1: Based on the traditional forging design method, the bottom of the barrel-shaped forging is generally designed to be flat. This design adds a two-step boss structure to the outer area of ​​the flat bottom of the forging;

[0028] Step 2: Based on the first step, the corresponding lower die or lower ejector die structure at the bottom of the forging is designed to match the shape;

[0029] Step 3: Based on the first and second steps, three-dimensional modeling of the designed forging and corresponding mold;

[0030] Step 4: Simulate the large special-shaped barrel forging and adjust the height and width of the two-step boss structure at the bottom of the forging as well as the matching shape and size of the lower die or lower ejector die according to the strain distribution of the large special-shaped barrel forging;

[0031] Step 5: Based on the above steps, analyze the streamline distribution of large special-shaped barrel forgings to ensure that the deformation of the parts to be processed is uniform, the streamlines are smooth, and the organizational performance requirements are met.

[0032] Furthermore, in the step one, the present design adds a two-step boss structure to the outer area of ​​the flat bottom of the forging. The boss can be an arc-shaped boss or a tapered boss. The width b0 of the flat bottom of the forging is 400~800mm, the height h1 of the first step is designed to be 20~50mm, the width b1 of the single side is 50~100mm, the height h2 of the second step platform is 50mm, the width b2 of the single side is 50~100mm, and the step draft angle is 15~30°.

[0033] Furthermore, the die obtained by the above design method to prevent the bottom deformation dead zone of large special-shaped barrel forgings is as follows: Figure 3 As shown in the figure, it is a typical cross section of the invention's large special-shaped barrel forging after adding a two-step boss structure. The corresponding lower die or lower ejector die cavity structure is as follows: Figure 4 The present invention adopts a design method of a special forging structure with a two-step boss at the bottom of the forging, and the strain distribution obtained after forming is as follows Figure 5 As shown in the figure, with the optimized design method, the deformation of the central deformation dead zone at the bottom of the forging is significantly increased, while the two deformation dead zones on both sides of the forging move outward and downward to below the area of ​​the parts to be processed, which greatly ensures the uniform strain distribution in the area of ​​the parts to be processed at the bottom of the large special-shaped barrel forging. Figure 6 The figure shows the streamline distribution obtained after forming. It can be seen that the streamline of the forging is smooth and reasonable by adopting the optimized design method.

[0034] In summary, the present invention, through the design of a special forging structure with a two-step boss on the bottom of the forging and a matching die shape, effectively increases the deformation of the central deformation dead zone at the bottom, preventing the possibility of a deformation dead zone in the center of the bottom. Simultaneously, the two deformation dead zones on either side are moved outward and downward below the area of ​​the part to be machined, thereby ensuring uniform strain distribution and smooth and reasonable flow lines in the area of ​​the part to be machined at the bottom of the large special-shaped barrel forging. This completely overcomes the problem of difficult-to-deform zones or deformation dead zones that often occur in forgings with flat bottom designs.

[0035] It can be seen that the present invention can effectively increase the deformation of the bottom center deformation dead zone by designing a special forging structure with a pit at the bottom of the forging and further thickened edges on both sides, and a matching mold shape, thereby preventing the possibility of a deformation dead zone in the bottom center area. At the same time, the two deformation dead zones on both sides can be moved outward and downward to below the area of ​​the part to be processed, thereby ensuring that the strain in the area of ​​the part to be processed at the bottom of the large barrel forging is evenly distributed and the streamline is smooth and reasonable.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the technical solutions. Those skilled in the art should understand that modifications or equivalent replacements of the technical solutions of the present invention that do not depart from the purpose and scope of the technical solutions of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A forging design method for preventing the deformation dead zone at the bottom of a large special-shaped barrel forging, characterized in that: The steps include: Step 1: Based on traditional forging design methods, the bottom of a barrel-shaped forging is generally designed to be flat. This design adds a two-step boss structure to the outer area of ​​the flat bottom of the forging. Step 2: Based on step 1, design the corresponding lower die and lower ejector die at the bottom of the forging to match the shape; Step 3: Based on steps 1 and 2, three-dimensional modeling of the designed forging and corresponding die is performed; Step 4: Simulate the large special-shaped barrel forging and adjust the height and width of the two-step boss structure at the bottom of the forging as well as the matching shape and size of the lower die and lower ejector die according to the strain distribution of the large special-shaped barrel forging; Step 5: Analyze the streamline distribution of large special-shaped barrel forgings to ensure that the deformation of the processing area is uniform, the streamline is smooth, and the organizational performance requirements are met; In step 1, a two-step boss structure is added to the outer area of ​​the flat bottom of the forging, wherein the width b0 of the flat bottom of the forging is 400~800mm, the height h1 of the first step platform is designed to be 20~50mm, the single-side width b1 is 50~100mm, the height h2 of the second step platform is 50mm, the single-side width b2 is 50~100mm, and the step draft angle is 15~30°.

2. A die for preventing the bottom deformation dead zone of a large special-shaped barrel forging, characterized in that: The forging design method for preventing the deformation dead zone at the bottom of a large special-shaped barrel forging is obtained according to claim 1.

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