Spinning forming method for complex curved generatrix shell with large length-diameter ratio and variable wall thickness

Abstract

The invention discloses a spinning forming method for a large-length-diameter-ratio variable-wall-thickness complex curved generatrix shell, and belongs to the technical field of metal pipe plastic machining. The specific process comprises the operation processes of blank size determination, primary machining, fixture and spinning roller determination, spinning forming, heat treatment and the like, the outer contour of a middle straight section is clamped, and then the two ends are subjected to hole shrinkage and thickening spinning. Through the machining mode that the two ends of the pipe are closed and subjected to die-free spinning, the defects and difficulties of common forging, extrusion and welding combined forming at present are overcome, the forming efficiency is improved, materials are saved, and the material utilization rate is high. Meanwhile, due to the fact that welding treatment is not conducted, heat treatment process operation is conducted finally, and the comprehensive mechanical property of a final finished product is more stable. The method is suitable for forming operation of various large-length-diameter-ratio variable-wall-thickness complex curved generatrix shells, and a reliable forming method can be provided for shell forming of spaceflight, weapons and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of plastic processing of metal pipes and relates to a spinning forming method for a complex curved busbar shell with a large aspect ratio, variable wall thickness, etc. Background Art

[0002] With the continuous development of aviation, aerospace, weapons, energy and other industries, complex curved busbar shells with large aspect ratio, variable wall thickness, etc. are widely used in fuel transportation, high and low temperature pressure bearing, and ammunition loading.

[0003] In terms of manufacturing technology, currently, the variable wall thickness complex curved busbar shell is mainly manufactured through forging, extrusion, welding and other processes. Since the forming thickness of the forged and extruded tube is much greater than the required thickness, a large amount of turning and boring processing is required for further finishing to achieve the required size requirements. This processing method has a high material waste rate, low processing efficiency, and large equipment occupation; at the same time, the level of welding technology also directly affects the quality and life of the shell, and has high requirements for welding equipment and operators.

[0004] Therefore, it is necessary to design and provide a spinning forming method suitable for complex curved busbar shells with large aspect ratio and variable wall thickness to solve the above-mentioned problems. Summary of the invention

[0005] The purpose of the present invention is to provide a method for spinning forming a complex curved busbar shell with a large aspect ratio and variable wall thickness. The forming process is flexible, and has the characteristics of high material utilization, high processing efficiency, strong adaptability, etc., and can improve the material strength performance.

[0006] The technical solution adopted by the present invention is a spinning forming method for a complex curved busbar shell with a large aspect ratio and variable wall thickness. The shell is a curved busbar rotating body with a large length-to-diameter ratio, a straight section in the middle, and complex outer contours at both ends. The method is implemented according to the following steps: S1. Determine the size of the blank according to the size structure and processing allowance of the finished shell: The blank is preset as a tubular blank according to the generatrix shape, and is determined according to the relationship that the volume before and after spinning remains basically unchanged; in, is the blank thickness, is the billet length, is the thickness of the finished spinning part, is the length of the finished spinning part; S2. Primary processing: Through extrusion and machining, the outer diameter is obtained , thickness is , length is Tubular spinning blank; S3, determine the fixture, the rotary wheel, the rotary wheel trajectory, and the rotary wheel feed ratio; S4, spinning; S5. Heat treatment: The blank that has been spun is subjected to stress relief heat treatment to finally obtain a finished product of a complex curved busbar shell with a large aspect ratio and variable wall thickness.

[0007] The present invention is also characterized in that: Furthermore, during the S4 spinning, a unidirectional spinning method is adopted to successively perform closing spinning on both ends of the blank; the specific process of closing spinning is as follows: Heating: heating the spinning deformation zone of the blank; Installation: Clamp the heated blank onto the spinning equipment through a fixture; Supplementary heating: Supplementary heating is performed on the blank after installation, and real-time monitoring is performed to ensure that the temperature of the deformation pressure zone meets the process requirements; Processing: When the temperature is appropriate, carry out spinning.

[0008] Furthermore, during the spinning process, the clamp is clamped at the straight section area of ​​the blank, and the length of the clamp is smaller than the length of the straight section of the original blank.

[0009] Furthermore, the clamp is a circumferentially split clamp.

[0010] Furthermore, the clamp is a circumferential 6-petal clamp.

[0011] Furthermore, the surface of the area where the clamp contacts the blank is provided with convex points.

[0012] Furthermore, the rotating wheel is made of tool steel or high-speed steel, and the surface roughness of the rotating wheel is 0.2 μm or above.

[0013] Furthermore, the outer shape of the rotating wheel is a single cone, and the attack angle of the rotating wheel is set to 42°~47°.

[0014] Furthermore, the fillet radius of the rotating wheel ranges from 2 mm to 20 mm.

[0015] Furthermore, the feed ratio of the rotary wheel is controlled at 0.3 mm / r~2.5 mm / r.

[0016] Furthermore, during heating in step S4, the heating temperature of the steel blank is 750°C to 800°C; the heating temperature of the aluminum alloy blank is 350°C to 400°C.

[0017] Furthermore, a supplementary heating module and a temperature measuring module are provided on the spinning equipment. The supplementary heating module is located below the blank processing area, and the temperature measuring module is located above the blank processing area. The supplementary heating module is used to supplement heating in the deformation zone, and at the same time, the temperature measuring module monitors the temperature of the deformation zone in real time and feeds back to the supplementary heating module. The supplementary heating module automatically adjusts the heating temperature according to the set temperature to ensure that the temperature of the deformation zone meets the process requirements.

[0018] Furthermore, the heat treatment temperature of the steel billet is 500℃~550℃, the holding time is 3h~4h, and it is cooled to below 400℃ in the furnace and then air-cooled; the heat treatment temperature of the aluminum alloy billet is 240℃~260℃, the holding time is 4h-6h, and it can be air-cooled.

[0019] The spinning forming method of the complex curved busbar shell with large aspect ratio and variable wall thickness of the present invention solves the shortcomings and difficulties of the current common forging, extrusion and welding combined forming through the dieless spinning processing mode of closing the ends of the tube material, improves the forming efficiency, saves materials, and has a high material utilization rate. At the same time, since it is not welded and the heat treatment process is finally performed, the comprehensive mechanical properties of the final finished product are more stable. It is suitable for various large aspect ratio and variable wall thickness complex curved busbar shell forming operations, and can provide a reliable forming method for the shell forming of aerospace, weapons, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the process of the present invention; Figure 2 It is a schematic diagram of a finished product of a complex curved busbar housing with a large aspect ratio and variable wall thickness according to the present invention; Figure 3 This is a schematic diagram of the operation of the blank A end during the spin forming process of the present invention; Figure 4 It is a schematic diagram of the operation of the blank B end during the spin forming process of the present invention.

[0021] In the figure, 1. spinning equipment; 2. fixture; 3. spinning wheel; 4. supplementary heating module; 5. temperature measurement module; 6. blank. DETAILED DESCRIPTION

[0022] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Traditional forging and extrusion processes require pre-processing of materials to obtain billets close to the target shape. A large amount of cutting of materials will cause a lot of material waste and reduce processing efficiency. The welding process requires multiple operations and has high requirements for welding equipment and operators. In addition, the welding quality is difficult to guarantee and welding defects are prone to occur, affecting the quality and life of the shell.

[0024] like Figure 1As shown, a method for spinning a complex curved busbar shell with a large aspect ratio and variable wall thickness of the present invention specifically includes determining the size of the blank, preliminary processing, determining the fixture 2 and the spinning wheel 3, spinning, and heat treatment.

[0025] S1. Determine the size of the blank 6 according to the size structure and machining allowance of the finished shell: like Figure 2 As shown, according to the structure of the finished product, the complex curved busbar shell with a large aspect ratio and variable wall thickness is generally of relatively large length and diameter, a straight section in the middle, and a complex curved busbar rotating body at both ends; for such finished products, the outer contour of the straight section in the middle can be clamped by a fixture 2, and then the two ends can be processed by a method of reducing the diameter and thickening the spinning.

[0026] The size of the original blank 6 is calculated based on the size structure and machining allowance of the final spinning product. The blank 6 can be preset as a tube blank according to the generatrix shape. According to the relationship that the volume before and after spinning remains roughly unchanged, the size of the blank before spinning is obtained: in, is the blank thickness, is the billet length, is the thickness of the finished spinning part, is the length of the finished spinning part.

[0027] S2. Primary processing: The outer diameter is obtained by extrusion, machining, etc. , thickness is , length is The tubular spinning blank is subjected to nondestructive testing to eliminate internal defects of the blank 6, as well as physical and chemical property testing.

[0028] S3, determine the fixture 2, the rotary wheel 3, the rotary wheel trajectory, and the rotary wheel feed ratio; Design of spinning fixture: For this type of spun part that is closed only at both ends, the clamp 2 is clamped in the straight section area in the middle where no spinning is performed, and the length of the clamp 2 is generally smaller than the length of the straight section at the clamping position; the clamp 2 mostly adopts a circumferentially divided clamp, and the clamp 2 of the present invention is divided into 6 circumferential petals; in order to prevent the blank 6 from moving during spinning, convex points are added to the inner surface of the clamp 2 to increase the friction between the clamp 2 and the blank 6 during spinning, thereby preventing the blank 6 from moving during spinning.

[0029] Rotating wheel design: The roller 3 is one of the main process equipment for spinning. It applies forming force to the workpiece. Under the action of friction, the spinning part drives the roller 3 to rotate at high speed. During the spinning process, the roller 3 is subjected to severe force and friction, so the roller 3 should have sufficient rigidity, hardness, heat resistance and good surface quality. The roller 3 is made of high-quality tool steel or high-speed steel, and the surface roughness of the roller 3 is 0.2μm or above.

[0030] For the closing spinning, in order to prevent the interference between the rotating wheel 3 and the blank 6, the attack angle of the rotating wheel 3 is set to 42°~47°, and the outer shape of the rotating wheel 3 is set to a single cone surface.

[0031] The fillet radius of the roller 3 has a significant impact on the forming process and the surface quality of the workpiece. The fillet radius of the roller 3 ranges from 2 mm to 20 mm. For blanks 6 with a thickness of 10 mm or more, the fillet radius of the roller 3 is set to 20 mm.

[0032] Draw the wheel trajectory: The motion trajectory of the roller 3 will affect the final size and surface quality of the spun part. For the closed and thickened spun parts, the diameter difference before and after closing is calculated and combined with the springback of the blank 6 to determine the amount of each downward pressure to draw the trajectory of the roller. The closed and thickened spinning is a multi-pass rolling forming of the roller, and the roller trajectory can be adjusted according to the actual spinning situation.

[0033] Programming the spinning program: According to the drawing of the spinning wheel trajectory, the corresponding spinning program is compiled, the program is simulated in the system, the correctness of the program is checked, and whether the spinning wheel 3 interferes with the spinning equipment 1 or the fixture 2 is checked.

[0034] Design spinning parameters: During spinning, the feed ratio of the spinning wheel has a significant effect on the spinning deformation, and the influence varies with the type of material and depends on the specific situation. The feed ratio of tubular spinning can be selected in the range of 0.3mm / r~2.5mm / r. If the surface roughness of the workpiece is not considered and there is a large reduction in diameter, a higher feed ratio can be used, which can be selected within 0.5mm / r~3mm / r.

[0035] S4, Spinning: The one-way spinning processing method is adopted to spin the two ends of the blank respectively.

[0036] like Figure 3 As shown, the spinning of the end A of the blank is specifically performed as follows: S4.1. Heat the spinning deformation zone at the A end of the blank, monitor the temperature in real time, and heat the temperature to the set temperature value. The heating temperature varies according to the material of the blank. Specifically, the heating temperature of steel is 700℃~800℃; the heating temperature of aluminum alloy is 300℃~400℃.

[0037] S4.2. After the temperature reaches the set temperature, the blank 6 is installed on the spinning equipment 1 by a lifting tool and clamped by a clamp 2. Pay attention to the clamping position during installation.

[0038] S4.3, the heating module 4 is used to perform heating in the spinning deformation area, and the temperature measurement module 5 monitors the temperature of the deformation area in real time and feeds back to the heating module 4. According to the set temperature, the heating module 4 automatically adjusts the heating temperature to ensure that the temperature of the deformation area meets the process requirements.

[0039] S4.4. When the temperature reaches the set temperature, start the spinning program to spin, and ensure that the temperature of the spinning deformation zone meets the process requirements. The heating temperature of steel parts is 750℃~800℃, and the heating temperature of aluminum alloy is 350℃~400℃; After the seam spinning is completed, check the size of the seam and record it.

[0040] After the end of the blank A is tested to meet the requirements, Figure 4 As shown, continue spinning the end B of the blank, the specific operations are as follows: S4.5. Heat the spinning deformation zone at the B end of the billet, monitor the temperature in real time, and heat the temperature to the set temperature value. Since the B end of the billet and the A end of the billet are made of the same material, the heating temperature is kept consistent. Similarly, the heating temperature of steel parts is 750℃~800℃; the heating temperature of aluminum alloy is 350℃~400℃.

[0041] S4.6. After the temperature reaches the set temperature, the blank 6 is installed on the spinning equipment 1 by the lifting tool and clamped by the clamp 2. Pay attention to the clamping position during installation.

[0042] S4.7, use the heating module 4 to perform heating in the spinning deformation area, and the temperature measurement module 5 monitors the temperature of the deformation area in real time and feeds back to the heating module 4. According to the set temperature, the heating module 4 automatically adjusts the heating temperature to ensure that the temperature of the deformation area meets the process requirements. The heating module 4 is located below the blank processing area, and the temperature measurement module 5 is located above the blank processing area.

[0043] S4.8. When the temperature reaches the set temperature, start the spinning program to spin, and ensure that the temperature of the deformation zone meets the process requirements during spinning. The temperature is consistent with the temperature of the billet A end during spinning operation. The heating temperature of steel parts is 750℃~800℃, and the heating temperature of aluminum alloy is 350℃~400℃.

[0044] After the B end of the blank is spun, the size of the spinning end is also detected and recorded.

[0045] S5. Heat treatment: During the spinning process, continuous heating and rolling of the blank will cause internal stress in the material. In order to prevent the spinning parts from deforming due to internal stress in the later stage, stress relief heat treatment is required. The stress relief heat treatment process needs to be formulated according to the material type and the performance requirements of the final product to eliminate internal stress, ensure the product size is stable, and the performance meets the design requirements.

[0046] Specifically, the heat treatment temperature of the steel billet is 500℃~550℃, the holding time is 3h~4h, and it is cooled to below 400℃ in the furnace and then air-cooled; the heat treatment temperature of the aluminum alloy billet is 240℃~260℃, the holding time is 4h~6h, and it can be air-cooled, and finally a finished product of a complex curved busbar shell with a large aspect ratio and variable wall thickness is obtained.

[0047] In order to further illustrate the technical solution of the present invention, the following specific embodiments are provided.

[0048] Example 1 The finished product of the complex curved busbar housing with large aspect ratio and variable wall thickness in this embodiment is a steel part with large aspect ratio, a straight section in the middle, and a complex curved busbar rotating body at both ends. The outer contour of the straight section in the middle is clamped by the fixture 2, and then the two ends are subjected to the processing method of shrinking the diameter and thickening the spinning. The specific specifications are: the thickness of the spinning finished product The length of the finished spinning part is 17mm The outer diameter of the finished spinning part is 280mm It is 100mm.

[0049] S1. Determine the size of the blank 6 according to the size structure and machining allowance of the finished shell: The size of the original blank 6 is calculated based on the size structure and machining allowance of the final spinning product. The blank 6 can be preset as a tube blank according to the generatrix shape. According to the relationship between the unchanged volume before and after spinning, the size of the blank before spinning is obtained: According to the above formula, determine the thickness of blank 6 15mm, length of blank 6 The outer diameter of blank 6 is 310 mm. It is 200mm.

[0050] S2. Primary processing: The tubular spinning blank 6 with the above-mentioned size requirements is obtained by extrusion, mechanical processing and the like, and the blank 6 is subjected to non-destructive testing to eliminate internal defects of the blank 6, as well as physical and chemical property testing.

[0051] S3, determine the fixture, the rotary wheel, the rotary wheel trajectory, and the rotary wheel feed ratio; Design of spinning fixture: For this type of spun part that only closes at both ends, the clamp 2 is clamped in the straight section area in the middle of the blank 6 that is not spun, and the length of the clamp 2 is generally less than the length of the straight section at the clamping position; the clamp 2 adopts a circumferentially split clamp, and the clamp 2 is divided into 6 petals in the circumferential direction. In order to prevent the blank 6 from moving during spinning, convex points are added to the inner surface of the clamp 2 to increase the friction between the clamp 2 and the blank 6 during spinning.

[0052] Rotating wheel design: The roller 3 is made of high-quality tool steel, and the surface roughness of the roller 3 is 0.2 μm.

[0053] For the closing spinning, in order to prevent the interference between the rotating wheel 3 and the blank 6, the attack angle of the rotating wheel 3 is set to 42°, and the outer shape of the rotating wheel 3 is set to a single cone.

[0054] The fillet radius of the rotating wheel 3 is 20 mm.

[0055] Draw the wheel trajectory: According to the diameter difference between before and after closing, combined with the rebound of the blank 6, the pressing amount each time is determined, and then the wheel trajectory is finally determined. Closing and thickening spinning are multi-pass rolling forming of the wheel, and the wheel trajectory is adjusted according to the actual spinning situation.

[0056] Programming the spinning program: According to the trajectory of the spinning wheel, the corresponding spinning program is compiled, the program is simulated in the system, the correctness of the program is checked, and whether the spinning wheel 3 interferes with the spinning equipment 1 or the fixture 2 is checked.

[0057] Design spinning parameters: The feed rate of the tubular spinning was set to 0.3 mm / r.

[0058] S4, Spinning: The one-way spinning processing method is adopted to spin the two ends of the blank respectively.

[0059] like Figure 3 As shown, the spinning of the end A of the blank is specifically performed as follows: S4.1. Heat the spinning deformation zone at the end A of the blank, monitor the temperature in real time, and heat the temperature to a set temperature value. In this embodiment, the heating temperature is 700°C.

[0060] S4.2. After the temperature reaches the set temperature, the blank 6 is installed on the spinning equipment 1 by a lifting tool and clamped by a clamp 2. Pay attention to the clamping position during installation.

[0061] S4.3, the heating module 4 is used to perform heating in the spinning deformation area, and the temperature measurement module 5 monitors the temperature of the deformation area in real time and feeds back to the heating module 4. According to the set temperature, the heating module 4 automatically adjusts the heating temperature to ensure that the temperature of the deformation area meets the process requirements.

[0062] S4.4, when the temperature reaches the set temperature, start the spinning program to perform spinning, and ensure that the temperature of the spinning deformation zone meets the process requirements during spinning. The heating temperature of this embodiment is 750°C; After the seam spinning is completed, check the size of the seam and record it.

[0063] After the end of the blank A is tested to meet the requirements, Figure 4 As shown, continue spinning the end B of the blank, the specific operations are as follows: S4.5. Heat the spinning deformation zone at the B end of the blank, monitor the temperature in real time, and heat the temperature to the set temperature value. Since the B end of the blank and the A end of the blank are made of the same material, the heating temperature is kept consistent. Similarly, the heating temperature is 750℃.

[0064] S4.6. After the temperature reaches the set temperature, the blank 6 is installed on the spinning equipment 1 by the lifting tool and clamped by the clamp 2. Pay attention to the clamping position during installation.

[0065] S4.7, the heating module 4 is used to perform heating in the spinning deformation area, and the temperature measurement module 5 monitors the temperature of the deformation area in real time and feeds back to the heating module 4. According to the set temperature, the heating module 4 automatically adjusts the heating temperature to ensure that the temperature of the deformation area meets the process requirements.

[0066] S4.8, when the temperature reaches the set temperature, start the spinning program to spin, and ensure that the temperature of the deformation zone meets the process requirements during spinning. The temperature is consistent with the temperature of the blank A end during spinning operation, and the heating temperature is 750℃.

[0067] After the B end of the blank is spun, the size of the spinning end is also detected and recorded.

[0068] S5. Heat treatment: The heat treatment temperature of the steel blank is 500°C, the holding time is 4h, and it is cooled to below 400°C in the furnace and then air-cooled to finally obtain a finished product of a complex curved busbar shell with a large aspect ratio and variable wall thickness.

[0069] Example 2 The finished product of the complex curved busbar housing with large aspect ratio and variable wall thickness in this embodiment is also a steel part, with a large aspect ratio, a straight section in the middle, and a complex curved busbar rotating body at both ends; the outer contour of the straight section in the middle is clamped by the clamp 2, and then the two ends are subjected to the processing method of shrinking the diameter and thickening the spinning. The specific specifications are: the thickness of the spinning finished product The length of the finished spinning part is 17mm The outer diameter of the finished spinning part is 300mm It is 95mm.

[0070] S1. Determine the size of the blank 6 according to the size structure and machining allowance of the finished shell: The size of the original blank 6 is calculated based on the size structure and machining allowance of the final spinning product. The blank 6 can be preset as a tube blank according to the generatrix shape. According to the relationship between the unchanged volume before and after spinning, the size of the blank before spinning is obtained: According to the above formula, determine the thickness of blank 6 15mm, length of blank 6 The outer diameter of the blank 6 is 340 mm. It is 200mm.

[0071] S2. Primary processing: The tubular spinning blank 6 with the above-mentioned size requirements is obtained by extrusion, mechanical processing and the like, and the blank 6 is subjected to non-destructive testing to eliminate the internal defects of the blank, as well as physical and chemical property testing.

[0072] S3, determine the fixture, the rotary wheel, the rotary wheel trajectory, and the rotary wheel feed ratio; Design of spinning fixture: For this type of spun parts that are only closed at both ends, the clamp 2 is clamped in the straight section area in the middle of the blank 6 where no spinning is performed, and the length of the clamp 2 is generally smaller than the length of the straight section at the clamping position; the clamp 2 adopts a circumferentially divided clamp, and the clamp 2 is divided into 6 lobes in the circumferential direction, and protrusions are provided on the inner surface of the clamp 2.

[0073] Rotating wheel design: The rotating wheel 3 is made of high-speed steel, and the surface roughness of the rotating wheel 3 is 0.3 μm.

[0074] In order to prevent the rotating wheel 3 from interfering with the blank 6, the attack angle of the rotating wheel 3 is set to 45°, and the outer shape of the rotating wheel 3 is set to a single cone.

[0075] The radius of the fillet of the rotating wheel 3 is in the range of 10 mm.

[0076] Draw the wheel trajectory: According to the diameter difference between before and after closing, combined with the rebound of the blank 6, the pressing amount each time is determined, and then the wheel trajectory is finally determined. Closing and thickening spinning are multi-pass rolling forming of the wheel, and the wheel trajectory is adjusted according to the actual spinning situation.

[0077] Programming the spinning program: According to the trajectory of the spinning wheel, the corresponding spinning program is compiled, the program is simulated in the system, the correctness of the program is checked, and whether the spinning wheel 3 interferes with the spinning equipment 1 or the fixture 2 is checked.

[0078] Design spinning parameters: In this embodiment, since the surface roughness of the workpiece is not considered, as long as there is a large reduction in diameter, the feed ratio is selected as 3mm / r.

[0079] S4, Spinning: The unidirectional spinning processing method is adopted to perform closing spinning on both ends of the blank 6 respectively.

[0080] like Figure 3 As shown, the spinning of the end A of the blank is specifically performed as follows: S4.1. Heat the spinning deformation zone at the A end of the blank, monitor the temperature in real time, and heat the temperature to a set temperature value. The heating temperature varies according to the material of the blank. In this embodiment, the heating temperature is 750°C.

[0081] S4.2. After the temperature reaches the set temperature, the blank 6 is installed on the spinning equipment 1 by a lifting tool and clamped by a clamp 2. Pay attention to the clamping position during installation.

[0082] S4.3, the heating module 4 is used to perform heating in the spinning deformation area, and the temperature measurement module 5 monitors the temperature of the deformation area in real time and feeds back to the heating module 4. According to the set temperature, the heating module 4 automatically adjusts the heating temperature to ensure that the temperature of the deformation area meets the process requirements.

[0083] S4.4. When the temperature reaches the set temperature, start the spinning program to perform spinning. During spinning, ensure that the temperature of the spinning deformation zone meets the process requirements. The heating temperature is 780°C. After the end of the spinning, check the size of the spinning end and record it.

[0084] After the end of the blank A is tested to meet the requirements, continue to spin the end of the blank B. The specific operations are as follows: S4.5. Heat the spinning deformation zone at the B end of the blank, monitor the temperature in real time, and heat the temperature to the set temperature value. Since the B end of the blank and the A end of the blank are made of the same material, the heating temperature is kept consistent. Similarly, the heating temperature is 780℃.

[0085] S4.6. After the temperature reaches the set temperature, the blank 6 is installed on the spinning equipment 1 by the lifting tool and clamped by the clamp 2. Pay attention to the clamping position during installation.

[0086] S4.7, the heating module 4 is used to perform heating in the spinning deformation area, and the temperature measurement module 5 monitors the temperature of the deformation area in real time and feeds back to the heating module 4. According to the set temperature, the heating module 4 automatically adjusts the heating temperature to ensure that the temperature of the deformation area meets the process requirements.

[0087] S4.8, when the temperature reaches the set temperature, start the spinning program to spin, and ensure that the temperature of the deformation zone meets the process requirements during spinning. The temperature is consistent with the temperature of the blank A end during spinning operation, and the heating temperature is 780℃.

[0088] After the B end of the blank is spun, the size of the spinning end is also detected and recorded.

[0089] S5. Heat treatment: The heat treatment temperature of the steel blank is 520℃, the holding time is 3.5h, and it is cooled to below 400℃ in the furnace and then air-cooled to finally obtain a finished product of a complex curved busbar shell with a large aspect ratio and variable wall thickness.

[0090] Example 3 The finished product of the complex curved busbar housing with large aspect ratio and variable wall thickness in this embodiment is a steel part with large aspect ratio, a straight section in the middle, and a complex curved busbar rotating body at both ends. The outer contour of the straight section in the middle is clamped by the fixture 2, and then the two ends are subjected to the processing method of shrinking the diameter and thickening the spinning. The specific specifications are: the thickness of the spinning finished product The length of the finished spinning part is 18mm The outer diameter of the finished spinning part is 200mm It is 80mm.

[0091] S1. Determine the size of the blank 6 according to the size structure and machining allowance of the finished shell: The size of the original blank 6 is calculated based on the size structure and machining allowance of the final spinning product. The blank 6 can be preset as a tube blank according to the generatrix shape. According to the relationship between the unchanged volume before and after spinning, the size of the blank before spinning is obtained: According to the above formula, determine the thickness of blank 6 17mm, length of blank 6 The outer diameter of blank 6 is 220 mm. It is 200mm.

[0092] S2. Primary processing: The tubular spinning blank 6 with the above-mentioned size requirements is obtained by extrusion, mechanical processing and the like, and the blank 6 is subjected to non-destructive testing to eliminate the internal defects of the blank, as well as physical and chemical property testing.

[0093] S3, determine the fixture, the rotary wheel, the rotary wheel trajectory, and the rotary wheel feed ratio; Design of spinning fixture: For this type of spun part that only closes at both ends, the clamp 2 is clamped in the straight section area in the middle of the blank 6 that is not spun, and the length of the clamp 2 is generally less than the length of the straight section at the clamping position; the clamp 2 adopts a circumferentially split clamp, and the clamp 2 is divided into 6 petals in the circumferential direction. Protrusions are added to the inner surface of the clamp 2 to increase the friction between the clamp 2 and the blank 6 during spinning.

[0094] Rotating wheel design: The rotating wheel 3 is made of high-speed steel, and the surface roughness of the rotating wheel 3 is 0.5 μm.

[0095] For the closing spinning, in order to prevent the interference between the rotating wheel and the blank, the attack angle of the rotating wheel 3 is set to 47°, and the outer shape of the rotating wheel 3 is set to a single cone.

[0096] The fillet radius of the rotating wheel 3 is 20 mm.

[0097] Draw the wheel trajectory: According to the diameter difference between before and after closing, combined with the rebound of the blank 6, the pressing amount each time is determined, and then the wheel trajectory is finally determined. Closing and thickening spinning are multi-pass rolling forming of the wheel, and the wheel trajectory is adjusted according to the actual spinning situation.

[0098] Programming the spinning program: According to the trajectory of the spinning wheel, the corresponding spinning program is compiled, the program is simulated in the system, the correctness of the program is checked, and whether the spinning wheel 3 interferes with the spinning equipment 1 or the fixture 2 is checked.

[0099] Design spinning parameters: The feed rate of the tubular spinning was set at 1.5 mm / r.

[0100] S4, Spinning: The unidirectional spinning processing method is adopted to perform closing spinning on both ends of the blank 6 respectively.

[0101] like Figure 3 As shown, the spinning of the end A of the blank is specifically performed as follows: S4.1. Heat the spinning deformation zone at the end A of the blank, monitor the temperature in real time, and heat the temperature to a set temperature value. The heating temperature varies according to the material of the blank. In this embodiment, the heating temperature is 800°C.

[0102] S4.2. After the temperature reaches the set temperature, the blank 6 is installed on the spinning equipment 1 by a lifting tool and clamped by a clamp 2. Pay attention to the clamping position during installation.

[0103] S4.3, the heating module 4 is used to perform heating in the spinning deformation area, and the temperature measurement module 5 monitors the temperature of the deformation area in real time and feeds back to the heating module 4. According to the set temperature, the heating module 4 automatically adjusts the heating temperature to ensure that the temperature of the deformation area meets the process requirements.

[0104] S4.4. When the temperature reaches the set temperature, start the spinning program to perform spinning. During spinning, ensure that the temperature of the spinning deformation zone meets the process requirements. The heating temperature of the steel part is 800℃. After the end of the spinning, check the size of the spinning end and record it.

[0105] After the end of the blank A is tested to meet the requirements, Figure 4 As shown, continue spinning the end B of the blank, the specific operations are as follows: S4.5. Heat the spinning deformation zone at the B end of the blank, monitor the temperature in real time, and heat the temperature to the set temperature value. Since the B end of the blank and the A end of the blank are made of the same material, the heating temperature is kept consistent. Similarly, the heating temperature of the steel part is 800℃.

[0106] S4.6. After the temperature reaches the set temperature, the blank 6 is installed on the spinning equipment 1 by the lifting tool and clamped by the clamp 2. Pay attention to the clamping position during installation.

[0107] S4.7, the heating module 4 is used to perform heating in the spinning deformation area, and the temperature measurement module 5 monitors the temperature of the deformation area in real time and feeds back to the heating module 4. According to the set temperature, the heating module 4 automatically adjusts the heating temperature to ensure that the temperature of the deformation area meets the process requirements.

[0108] S4.8, when the temperature reaches the set temperature, start the spinning program to spin, and ensure that the temperature of the deformation zone meets the process requirements during spinning. The temperature is consistent with the temperature of the blank A end during spinning operation, which is set to 800℃.

[0109] After the B end of the blank is spun, the size of the spinning end is also detected and recorded.

[0110] S5. Heat treatment: The heat treatment temperature of the steel blank is 550°C, the holding time is 3h, and it is cooled to below 400°C in the furnace and then air-cooled to finally obtain a finished product of a complex curved busbar shell with a large aspect ratio and variable wall thickness.

[0111] Example 4 The finished product of the complex curved busbar housing with large aspect ratio and variable wall thickness in this embodiment is made of aluminum alloy, with a large aspect ratio, a straight section in the middle, and a complex curved busbar rotating body at both ends. The outer contour of the straight section in the middle is clamped by the fixture 2, and then the two ends are subjected to the processing method of shrinking the diameter and thickening the spinning. The specific specifications are: the thickness of the spinning finished product The length of the finished spinning part is 18mm The outer diameter of the finished spinning part is 300mm It is 80mm.

[0112] S1. Determine the size of the blank 6 according to the size structure and machining allowance of the finished shell: The size of the original blank 6 is calculated based on the size structure and machining allowance of the final spinning product. The blank 6 can be preset as a tube blank according to the generatrix shape. According to the relationship between the unchanged volume before and after spinning, the size of the blank before spinning is obtained: According to the above formula, determine the thickness of blank 6 17mm, length of blank 6 The outer diameter of the blank 6 is 330 mm. It is 200mm.

[0113] S2. Primary processing: The tubular spinning blank 6 with the above-mentioned size requirements is obtained by extrusion, mechanical processing and the like, and the blank 6 is subjected to non-destructive testing to eliminate the internal defects of the blank, as well as physical and chemical property testing.

[0114] S3, determine the fixture, the rotary wheel, the rotary wheel trajectory, and the rotary wheel feed ratio; Design of spinning fixture: For this type of spun part that only closes at both ends, the clamp 2 is clamped in the straight section area in the middle of the blank 6 that is not spun, and the length of the clamp 2 is generally less than the length of the straight section at the clamping position; the clamp 2 adopts a circumferentially split clamp, and the clamp 2 is divided into 6 petals in the circumferential direction. In order to prevent the blank 6 from moving during spinning, convex points are added to the inner surface of the clamp 2 to increase the friction between the clamp 2 and the blank 6 during spinning.

[0115] Rotating wheel design: The rotating wheel 3 is made of high-speed steel, and the surface roughness of the rotating wheel 3 is 0.3 μm.

[0116] For the closing spinning, in order to prevent the interference between the rotating wheel and the blank, the attack angle of the rotating wheel 3 is set to 45°, and the outer shape of the rotating wheel 3 is set to a single cone.

[0117] The fillet radius of the rotating wheel 3 is 15 mm.

[0118] Draw the wheel trajectory: According to the diameter difference between before and after closing, combined with the rebound of the blank 6, the pressing amount each time is determined, and then the wheel trajectory is finally determined. Closing and thickening spinning are multi-pass rolling forming of the wheel, and the wheel trajectory is adjusted according to the actual spinning situation.

[0119] Programming the spinning program: According to the trajectory of the spinning wheel, the corresponding spinning program is compiled, the program is simulated in the system, the correctness of the program is checked, and whether the spinning wheel 3 interferes with the spinning equipment 1 or the fixture 2 is checked.

[0120] Design spinning parameters: The feed rate of spinning tubular parts is set to 2mm / r. If the surface roughness of the workpiece is not considered and there is a large reduction in diameter, a higher feed rate, such as 3mm / r, can be used.

[0121] S4, Spinning: The unidirectional spinning processing method is adopted to perform closing spinning on both ends of the blank 6 respectively.

[0122] like Figure 3 As shown, the spinning of the end A of the blank is specifically performed as follows: S4.1. Heat the spinning deformation zone at the end A of the blank, monitor the temperature in real time, and heat the temperature to a set temperature value. The heating temperature varies according to the material of the blank, and the heating temperature in this embodiment is 300°C.

[0123] S4.2. After the temperature reaches the set temperature, the blank 6 is installed on the spinning equipment 1 by a lifting tool and clamped by a clamp 2. Pay attention to the clamping position during installation.

[0124] S4.3, the heating module 4 is used to perform heating in the spinning deformation area, and the temperature measurement module 5 monitors the temperature of the deformation area in real time and feeds back to the heating module 4. According to the set temperature, the heating module 4 automatically adjusts the heating temperature to ensure that the temperature of the deformation area meets the process requirements.

[0125] S4.4. When the temperature reaches the set temperature, start the spinning program to perform spinning. During spinning, ensure that the temperature of the spinning deformation zone meets the process requirements. The heating temperature is 350°C. After the end of the spinning, check the size of the spinning end and record it.

[0126] After the end of the blank A is tested to meet the requirements, Figure 4 As shown, continue spinning the end B of the blank, the specific operations are as follows: S4.5. Heat the spinning deformation zone at the B end of the blank, monitor the temperature in real time, and heat the temperature to the set temperature value. Since the B end of the blank and the A end of the blank are made of the same material, the heating temperature is kept consistent. Similarly, the heating temperature is 350°C.

[0127] S4.6. After the temperature reaches the set temperature, the blank 6 is installed on the spinning equipment 1 by the lifting tool and clamped by the clamp 2. Pay attention to the clamping position during installation.

[0128] S4.7, the heating module 4 is used to perform heating in the spinning deformation area, and the temperature measurement module 5 monitors the temperature of the deformation area in real time and feeds back to the heating module 4. According to the set temperature, the heating module 4 automatically adjusts the heating temperature to ensure that the temperature of the deformation area meets the process requirements.

[0129] S4.8, when the temperature reaches the set temperature, start the spinning program to spin, and ensure that the temperature of the deformation zone meets the process requirements during spinning. The temperature is consistent with the temperature of the blank A end during spinning operation, and the heating temperature is 350℃.

[0130] After the B end of the blank is spun, the size of the spinning end is also detected and recorded.

[0131] S5. Heat treatment: The heat treatment temperature of the aluminum alloy billet is 240°C, the holding time is 6 hours, and air cooling is sufficient to finally obtain a finished product of a complex curved busbar shell with a large aspect ratio and variable wall thickness.

[0132] Example 5 The material of the blanks in this embodiment and embodiment 4 is the same, both are aluminum alloys, and the forming methods are the same, and the only difference is the heat treatment temperature and holding time. Specifically, the heat treatment temperature of the aluminum alloy blank is 250°C, the holding time is 5 hours, and air cooling is sufficient, and finally a finished product of a complex curved busbar shell with a large aspect ratio and variable wall thickness is obtained.

[0133] Example 6 The material of the blanks in this embodiment is the same as that in embodiment 4 and embodiment 5, which is aluminum alloy, and the forming method is the same. The only difference is the heat treatment temperature and holding time. Specifically, the heat treatment temperature of the aluminum alloy blank is 260°C, the holding time is 4 hours, and air cooling is sufficient, and finally a finished product of a complex curved busbar shell with a large aspect ratio and variable wall thickness is obtained.

[0134] The finished product of the complex curved busbar shell with a large aspect ratio and variable wall thickness processed in the above embodiment is a rotating body with a complex and changing curved surface contour. Spin forming can realize this surface contour more flexibly and accurately. Compared with combined forming methods such as welding process, this forming method improves the comprehensive mechanical properties of the finished product of the complex curved busbar shell with a large aspect ratio and variable wall thickness, and increases the service life of the product.

[0135] The present invention adopts a spinning forming process, and applies plastic deformation to the tubular blank through a rotating wheel, so that it is gradually shaped into a shell of a target shape. The method utilizes the plastic flow characteristics of the material under stress, and gradually shapes the blank into a desired shape through the rotation and feeding of the wheel. Compared with the traditional forging, extrusion, and welding combined forming methods, this method directly plastically deforms the blank through the dieless spinning processing method of closing the ends of the tube material, without excessive pre-processing or welding, which greatly improves the processing efficiency, high material utilization rate, and reduces production costs. The spinning forming process can make the grain structure of the metal material more refined, and generate stress inside the material, thereby improving the strength, toughness, and fatigue resistance of the material. At the same time, the present invention performs stress relief heat treatment on the blank after the spinning process, further improving the strength performance of the material and ensuring that the shell has good load-bearing capacity.

[0136] The spinning process can realize the forming of complex curved surfaces without shape restrictions, and is suitable for various large aspect ratio variable wall thickness complex curved busbar shell forming operations. The processing parameters, such as the feed speed of the spinning wheel and the shape of the spinning wheel, can be adjusted according to the characteristics of different materials to obtain the best forming effect. The forming efficiency is improved, materials are saved, and the material utilization rate is high. Since it is not welded and the heat treatment process is performed at the end, the comprehensive mechanical properties of the final finished product are more stable. It is suitable for various large aspect ratio variable wall thickness complex curved busbar shell forming operations, and can provide a reliable forming method for the shell forming of aerospace, weapons, etc.

[0137] Therefore, the present invention has important application value and can effectively improve the efficiency and quality of the manufacturing process of complex curved busbar shells with large aspect ratio and variable wall thickness, and provide more economical, efficient and reliable solutions for the fields of aviation, aerospace, weapons, etc.

Claims

1. A spinning forming method for a complex curved busbar housing with a large aspect ratio and variable wall thickness, characterized in that: The shell is a rotating body with a large length-to-diameter ratio, a straight section in the middle, and complex curved generatrix outer contours at both ends, and is implemented according to the following steps: S1. Determine the size of the blank (6) according to the size structure and machining allowance of the finished shell: The blank (6) is preset as a tubular blank according to the generatrix shape, and is determined according to the relationship that the volume before and after spinning remains substantially unchanged; in, is the thickness of the blank (6), is the length of the blank (6), is the thickness of the finished spinning part, is the length of the finished spinning part; S2. Primary processing: Through extrusion and machining, the outer diameter is obtained , thickness is , length is A tubular spinning blank (6); S3, determining the fixture (2), the rotary wheel (3), the rotary wheel trajectory, and the rotary wheel feed ratio; S4, spinning; S5. Heat treatment: The blank (6) that has undergone the spinning treatment is subjected to stress relief heat treatment, and finally a finished product of a complex curved busbar housing with a large aspect ratio and variable wall thickness is obtained.

2. The method for spinning a complex curved busbar housing with a large aspect ratio and variable wall thickness according to claim 1 is characterized in that: The S4 spinning process adopts a unidirectional spinning method, and the two ends of the blank (6) are respectively subjected to closing spinning. The specific process of the closing spinning is as follows: Heating: heating the spinning deformation zone of the blank (6); Installation: The heated blank (6) is clamped on the spinning device (1) by a clamp (2); repair Heating: reheating the installed blank (6) and monitoring it in real time to ensure that the temperature of the deformation pressure zone meets the process requirements; Processing: When the temperature is appropriate, carry out spinning.

3. The method for spinning forming a complex curved busbar housing with a large aspect ratio and variable wall thickness according to claim 1 is characterized in that: The clamp (2) is a circumferentially split clamp.

4. The method for spinning forming a complex curved busbar housing with a large aspect ratio and variable wall thickness according to claim 1 is characterized in that: The rotating wheel (3) is made of tool steel or high-speed steel, and the surface roughness of the rotating wheel (3) is 0.2 μm or above.

5. The method for spinning forming a complex curved busbar housing with a large aspect ratio and variable wall thickness according to claim 1 is characterized in that: The outer shape of the rotating wheel (3) is a single cone, and the attack angle of the rotating wheel (3) is set to 42° to 47°.

6. The method for spinning forming a complex curved busbar housing with a large aspect ratio and variable wall thickness according to claim 1 is characterized in that: The fillet radius of the rotating wheel (3) ranges from 2 mm to 20 mm.

7. The method for spinning forming a complex curved busbar housing with a large aspect ratio and variable wall thickness according to claim 1 is characterized in that: The feed ratio of the rotating wheel (3) is controlled within a range of 0.3 mm / r to 2.5 mm / r.

8. The method for spinning forming a complex curved busbar housing with a large aspect ratio and variable wall thickness according to claim 1 is characterized in that: During heating in step S4, the heating temperature of the steel blank is 750°C to 800°C; the heating temperature of the aluminum alloy blank is 350°C to 400°C.

9. The method for spinning a complex curved busbar housing with a large aspect ratio and variable wall thickness according to claim 2, characterized in that: The spinning device (1) is provided with a heating module (4) and a temperature measurement module (5), wherein the heating module (4) is located below the blank processing zone, and the temperature measurement module (5) is located above the blank processing zone; the heating module (4) performs heating in the deformation zone, while the temperature measurement module (5) monitors the temperature of the deformation zone in real time and feeds back to the heating module (4); the heating module (4) automatically adjusts the heating temperature according to the set temperature to ensure that the temperature of the deformation zone meets the process requirements.

10. The method for spinning forming a complex curved busbar housing with a large aspect ratio and variable wall thickness according to claim 1, characterized in that: The heat treatment temperature of the steel billet is 500℃~550℃, the holding time is 3h~4h, and it is cooled to below 400℃ with the furnace and then air-cooled; the heat treatment temperature of the aluminum alloy billet is 240℃~260℃, the holding time is 4h~6h, and air-cooling is sufficient.

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