A forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer.

Abstract

This application discloses a forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer, relating to the field of forging technology. Specifically, the forging method involves upsetting and shaping a pre-modified billet to obtain a billet matrix. Then, a positioning recess is pressed into the billet matrix using a small first pressure head. The first pressure head, second pressure head, ..., Nth pressure head are then pressed in sequentially from bottom to top, with the Nth pressure head held within the billet matrix to shape the billet matrix, thereby obtaining a forging blank. Compared to traditional methods for processing bowl-shaped workpieces, this forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer not only effectively reduces material usage, saving material and lowering costs, but also saves machining time and improves production efficiency.

Description

Technical Field

[0001] This invention relates to the field of forging technology, specifically a forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer. Background Technology

[0002] Bowl-shaped workpieces, as the name suggests, are forgings with a concave cross-section and an axisymmetric shape, such as... Figure 1 As shown. Bowl-shaped workpieces are widely used in heavy machinery, pressure vessels, automobile manufacturing, and other fields, and are a widely used form of forging.

[0003] Because hydraulic presses operate using a slow, static pressure method, when forming the concave portion of a bowl-shaped workpiece, significant material residue accumulates at the edges, making it difficult to achieve proper forming and ensure the final dimensional accuracy. Therefore, currently, bowl-shaped forgings are typically forged into rectangular blanks, with the concave portion of the bowl shape then machined. This method uses more material, and machining the concave portion of the bowl shape is time-consuming and difficult, increasing production costs and reducing processing efficiency. Summary of the Invention

[0004] To address the aforementioned issues, this application provides a forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer, which not only saves materials and reduces production costs but also improves processing efficiency.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] A forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer, comprising the following steps:

[0007] S1, the billet is upholstered and drawn to complete the material transformation process;

[0008] S2, Upset the billet to a set height and shape it to obtain the billet matrix;

[0009] S3, machining positioning recesses in the blank substrate;

[0010] 3.1 Place a punching alignment template on the billet substrate and align the center hole of the punching alignment template with the geometric center of the billet substrate;

[0011] 3.2 Insert the first pressure head into the center hole of the punching alignment template;

[0012] 3.3 Start the pressure equipment and press the first pressure head into the billet matrix to form a positioning recess on the billet matrix;

[0013] S4, the conical first pressure head is placed into the positioning recess, and the first pressure head is pressed into the billet matrix by the pressure device to form a primary recess with a depth of H2 on the billet matrix;

[0014] S5, the conical second pressure head is placed into the primary pit, and the pressure device is used to press the second pressure head into the primary pit, thereby expanding the primary pit to form a secondary pit;

[0015] S6. Repeat step S5 until the Nth indenter is pressed into the N-1th indentation, forming the Nth indentation.

[0016] S7, keep the Nth pressure head in the billet matrix and shape the billet matrix.

[0017] Furthermore, in step 3.2, the depth H1 of the first pressure head pressing into the billet matrix satisfies...

[0018]

[0019] In the formula: P is the thickness of the punching alignment template;

[0020] D is the diameter of the center hole of the punching alignment template;

[0021] β is the taper of the first indenter;

[0022] B1 is the diameter of the small end of the first indenter.

[0023] Furthermore, in step 3.2, the depth H1 of the first pressure head pressing into the billet matrix ranges from 15 to 30 mm.

[0024] Furthermore, the small end diameter of the Nth pressure head is less than or equal to the large end diameter of the (N-1)th pressure head.

[0025] Furthermore, N is 3, the large end diameter of the first pressure head is equal to the small end diameter of the second pressure head, and the large end diameter of the second pressure head is equal to the small end diameter of the third pressure head.

[0026] Furthermore, the taper of the first pressure head, the second pressure head...the Nth pressure head is 15-25°.

[0027] Furthermore, the small ends of the first pressure head, the second pressure head...the Nth pressure head are rounded.

[0028] Furthermore, the height of the Nth pressure head is greater than H2.

[0029] Furthermore, the height of the first pressure head, the second pressure head... the (N-1)th pressure head is greater than H2.

[0030] Furthermore, the first pressure head, the second pressure head... the Nth pressure head each includes a cylindrical section and a conical section in sequence along the direction near the small end. The height of the conical section is equal to H2, and the height L1 of the cylindrical section is 30-60mm.

[0031] The beneficial effects of this invention are:

[0032] 1. The forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer provided in this application embodiment generates almost no waste compared to traditional methods for processing bowl-shaped workpieces, effectively reducing material usage, saving materials, and lowering costs. Experiments have shown that the forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer provided in this application embodiment can save 16.5% of raw material usage, effectively reducing raw material procurement costs.

[0033] 2. The forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer provided in this application embodiment can achieve one-time forming without secondary processing (machining), thus effectively improving production efficiency. Experiments have shown that using the forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer provided in this application embodiment can save approximately 10% of machining time, improving production efficiency and reducing processing costs.

[0034] 3. The forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer provided in this application embodiment ensures the integrity of the metal flow lines of the forging, and the use of a pressure head forming method is equivalent to center compaction, which is more conducive to the UT pass rate of blind plate forgings.

[0035] 4. The bowl-shaped workpiece with a near-net-shape forming method on a hammer provided in the embodiments of this application has better concave formation, and the edge end face of the concave is flat, without the situation of being skewed by the press head during press forming. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the structure of a bowl-shaped workpiece;

[0037] Figure 2 This is a schematic diagram of the structure of the first pressure head;

[0038] Figure 3 This is a schematic diagram of the second pressure head;

[0039] Figure 4 This is a schematic diagram of the third pressure head;

[0040] Figure 5 A structural diagram of a punching alignment template;

[0041] Figure 6 A schematic diagram of the structure during the machining of the positioning recess;

[0042] Figure 7 A schematic diagram of the blank substrate after the positioning recess has been machined;

[0043] Figure 8 This is a schematic diagram of the structure after the first pressure head is pressed into the billet matrix;

[0044] Figure 9 A schematic diagram showing the structure for placing the second pressure head into the primary recess;

[0045] Figure 10 This is a schematic diagram of the structure after the second pressure head is pressed into the billet matrix.

[0046] In the diagram: 1. Blank substrate; 11. Positioning recess; 12. Primary recess;

[0047] 2. Punching and alignment template; 21. Center hole;

[0048] 31. First pressure head; 32. Second pressure head; 33. Third pressure head. Detailed Implementation

[0049] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be described in detail below with reference to the accompanying drawings. The described embodiments are merely a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort should fall within the protection scope of this application.

[0050] A forging method for near-net-shape forming of a bowl-shaped workpiece on a hammer includes the following steps:

[0051] S1 involves roughing and elongating the billet to complete the material transformation process.

[0052] After the billet undergoes upsetting and drawing processes, defects such as porosity inside the steel ingot can be improved to meet the requirements of UT testing in the later stages of forging.

[0053] S2, After the material change is completed, the billet is upset to the set height and shaped to obtain the billet base 1. The shaping process can obtain a regular-shaped billet base 1, which makes it easier to find the center in subsequent processing.

[0054] S3, the blank substrate 1 obtained in step S2 is machined with positioning recesses 11.

[0055] 3.1 such as Figure 5 and Figure 6 As shown, the blank substrate 1 is placed in the processing position of the pressure equipment, and the punching alignment template 2 is placed on the upper side of the blank substrate 1, and the center hole 21 of the punching alignment template 2 is aligned with the geometric center of the blank substrate 1.

[0056] 3.2 such as Figure 6 As shown, the first pressure head 31 is inserted into the center hole 21 of the punching alignment template 2, and the first pressure head 31 is kept coaxial with the center hole 21 of the punching alignment template 2.

[0057] 3.3 Start the pressure equipment and press the first pressure head 31 into the billet substrate 1, thereby forming a shape on the billet substrate 1 as shown in the figure. Figure 7 The positioning recess 11 shown is used as the positioning reference for subsequent punching.

[0058] 3.4 Lift the pressure head of the pressure equipment, remove the first pressure head 31 and the punching alignment template 2.

[0059] In one specific embodiment, the shape of the punching alignment template 2 is exactly the same as the shape of the blank substrate 1, and the center hole 21 is located at the geometric center of the punching alignment template 2. When the punching alignment template 2 is placed on the upper side of the blank substrate 1 and the edge of the punching alignment template 2 is completely aligned with the edge of the blank substrate 1, the position of the center hole 21 of the punching alignment template 2 is the geometric center of the blank substrate 1.

[0060] Further, the thickness of the punching alignment template 2 is P, the diameter of the central hole 21 of the punching alignment template 2 is D, the taper of the first pressure head 31 is β, the diameter of the small end of the first pressure head 31 is B1, and the depth H1 of the first pressure head 31 pressing into the blank substrate 1 in step 3.2 satisfies .

[0061] Preferably, the depth H1 of the first pressing head 31 pressing into the blank substrate 1 in step 3.2 is in the range of 15-30mm. As a specific embodiment, the depth H1 of the first pressing head 31 pressing into the blank substrate 1 in step 3.2 of this embodiment is 20mm.

[0062] S4, spray release agent into the positioning recess 11, place the first pressure head 31 with a conical structure into the positioning recess 11, with the small end of the first pressure head 31 facing downwards, and then start the pressure equipment, such as... Figure 8 As shown, a first pressure head 31 is pressed into the blank substrate 1 using a pressure device, forming a primary recess 12 with a depth of H2 on the blank substrate 1, that is, the pressing depth of the first pressure head 31 is H2. Then the first pressure head 31 is removed from the primary recess 12.

[0063] The pressing depth H2 of the first pressure head 31 is the design dimension of the forging blank.

[0064] In one specific implementation, the design depth of the concave portion of the bowl-shaped workpiece in this embodiment is 260mm, and the design depth of the concave portion of the forging blank used to process the bowl-shaped workpiece is 250mm (leaving a processing allowance of 10mm). Therefore, the pressing depth H2 of the first pressing head 31 in step S4 is 250mm.

[0065] S5, spray a release agent into the recess 12 formed in step S4, such as Figure 9 As shown, the second pressure head 32, which has a conical structure, is placed into the primary recess 12 formed in step S4, with the small end of the second pressure head 32 facing downwards. Then, the pressure device is started. Figure 10 As shown, a second pressure head 32 is pressed into the primary recess 12 using a pressure device, thereby enlarging the primary recess 12 formed in step S4 and forming a secondary recess with the same depth as the primary recess 12. Then, the second pressure head 32 is removed from the secondary recess.

[0066] S6. Repeat step S5 until the Nth pressure head is pressed into the N-1th recess obtained in the previous step, forming an Nth recess with the same depth as the first recess 12, and the size of the Nth recess (including depth, taper and diameter) is equal to the size of the concave part of the forging blank.

[0067] The small end diameter of the Nth pressure head is less than or equal to the large end diameter of the (N-1)th pressure head. Preferably, the small end diameter of the Nth pressure head is equal to the large end diameter of the (N-1)th pressure head. In this way, the large and small ends of the N pressure heads are connected sequentially, and the large end diameter of the front pressure head is the small end diameter of the rear pressure head, which can reduce the probability of burrs during pressing and improve the molding quality.

[0068] In one specific implementation, N is 3 in this embodiment, meaning the pressure head group includes a first pressure head 31, a second pressure head 32, and a third pressure head 33 in ascending order. For example... Figure 2 , Figure 3 and Figure 4 As shown, the large end diameter A1 of the first pressure head 31 is equal to the small end diameter B2 of the second pressure head 32, and the large end diameter A2 of the second pressure head 32 is equal to the small end diameter B3 of the third pressure head 33.

[0069] Applying a release agent before pressing the mold head helps the mold head to come out smoothly.

[0070] Furthermore, the taper β of the first pressure head 31, the second pressure head 32... the Nth pressure head is 15-25°, and this taper design facilitates the smooth insertion and removal of the pressure head.

[0071] In one specific implementation, the taper β of the first pressure head 31, the second pressure head 32...the Nth pressure head is 23°.

[0072] Furthermore, the small ends of the first pressure head 31, the second pressure head 32... the Nth pressure head are rounded to ensure that the bottom is not damaged when pressing into the blank.

[0073] S7, keep the Nth pressure head inside the blank base 1 and shape the blank base 1 to obtain the designed external shape, such as a circle or a square. After the shaping is completed, remove the Nth pressure head to obtain the forging blank of the bowl-shaped workpiece.

[0074] Furthermore, the height of the Nth pressure head is greater than the depth H2 of the concave portion of the forging blank. This prevents the Nth pressure head from being encased in the forging recess during shaping.

[0075] Furthermore, the height of the first pressure head 31, the second pressure head 32... the (N-1)th pressure head is greater than the depth H2 of the concave portion of the forging blank.

[0076] Furthermore, the first pressure head 31, the second pressure head 32... the Nth pressure head sequentially include a cylindrical section and a conical section along the direction near the small end, and the height L2 of the conical section is equal to the depth H2 of the concave portion of the forging blank. The height L1 of the cylindrical section is 30-60mm.

[0077] In one specific implementation, the height L1 of the cylindrical segment in this embodiment is 50mm.

[0078] By setting a cylindrical section, the pressing depth of the pressure head can be visually observed, thus avoiding excessive pressing that would result in insufficient machining allowance for the concave part of the forging blank.

[0079] Furthermore, the pressure device is an electro-hydraulic hammer. Compared to the static pressure method of a hydraulic press, the electro-hydraulic hammer is a dynamic load with a fast striking speed and large instantaneous impact force. It can quickly change the shape of the forging, making it more suitable for forming bowl-shaped workpieces and more advantageous for forming the concave center of the bowl-shaped workpiece.

[0080] As one specific implementation, the pressure device described in this embodiment is a 10-ton electro-hydraulic hammer.

[0081] Other embodiments obtained by those skilled in the art based on the embodiments provided in this application by combining, splitting, or reorganizing the embodiments of this application do not exceed the protection scope of this application.

[0082] The above detailed embodiments have provided a detailed explanation of the purpose, technical solutions, and beneficial effects of the embodiments of this application. The above are merely specific embodiments of the embodiments of this application and are not intended to limit the protection scope of the embodiments of this application. That is, any modifications, equivalent substitutions, improvements, etc., made on the basis of the embodiments of this application should be included within the protection scope of the embodiments of this application.

Claims

1. A method of forging a bowl-shaped workpiece on a near-net shape hammer, characterized by: Includes the following steps, S1, the billet is upset and drawn to complete the material transformation process; S2, the billet is upturned to a set height and shaped to obtain the billet matrix (1). S3, a positioning recess (11) is machined in the blank substrate (1). 3.1 Place a punching alignment template (2) on the blank substrate (1) and align the center hole (21) of the punching alignment template (2) with the geometric center of the blank substrate (1); 3.2 Insert the first pressure head (31) into the center hole (21) of the punching alignment template (2); 3.3 Start the pressure equipment and press the first pressure head (31) into the billet substrate (1) to form a positioning pit (11) on the billet substrate (1). S4, the conical first pressure head (31) is placed into the positioning recess (11), and the first pressure head (31) is pressed into the blank substrate (1) by the pressure device, forming a primary recess (12) with a depth of H2 on the blank substrate (1). S5, the conical second pressure head (32) is placed into the primary recess (12), and the second pressure head (32) is pressed into the primary recess (12) by the pressure device, thereby expanding the primary recess (12) to form a secondary recess; S6. Repeat step S5 until the Nth indenter is pressed into the N-1th indentation, forming the Nth indentation. S7, keep the Nth pressure head inside the billet matrix (1) and shape the billet matrix (1); In step 3.2, the depth H1 of the first pressure head (31) pressing into the billet matrix (1) satisfies In the formula: P is the thickness of the punching alignment template (2); D is the diameter of the center hole (21) of the punching alignment template (2); β is the taper of the first indenter (31); B1 is the diameter of the small end of the first pressure head (31); The taper of the first pressure head (31), the second pressure head (32) ... the Nth pressure head is 15-25°; The height of the Nth pressure head is greater than H2; The heights of the first pressure head (31), the second pressure head (32), ... the (N-1)th pressure head are greater than H2; The first pressure head (31), the second pressure head (32) ... the Nth pressure head each include a cylindrical section and a conical section in sequence along the direction close to the small end. The height of the conical section is equal to H2, and the height L1 of the cylindrical section is 30-60mm. N is 3, the large end diameter of the first pressure head (31) is equal to the small end diameter of the second pressure head (32), and the large end diameter of the second pressure head (32) is equal to the small end diameter of the third pressure head (33).

2. A method of near-net shape forging of a bowl-shaped workpiece on a bowl machine as defined in claim 1, wherein: In step 3.2, the depth H1 of the first pressure head (31) pressing into the blank matrix (1) is 15-30mm.

3. A method of near net shape forging of a bowl-shaped workpiece on a bowl- shaped workpiece hammer as defined in claim 1, wherein: The small ends of the first pressure head (31), the second pressure head (32) and the third pressure head (33) are rounded.

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