Low-temperature impact-resistant multi-pressing stainless steel component progressive die and stamping method

Abstract

The present application belongs to the technical field of stamping, and particularly relates to a low-temperature impact-resistant multi-bending stainless steel component progressive die and a stamping method. The die comprises a base, a blanking die and a material punching die arranged on the base, and further comprises a second-stage double-punch bending unit and a third-stage bending unit arranged between the blanking die and the material punching die in sequence. A stainless steel progressive die material plate passes through the blanking die, the second-stage double-punch bending unit, the third-stage bending unit and the material punching die in sequence along a stepping direction to complete the blanking, double-sided punch bending, double-sided bending and material punching processes in sequence, and a multi-bending stainless steel component is obtained. The present application realizes full control of the bending deformation of the multi-bending stainless steel component, effectively prevents local microscopic martensite phase change of the compression strain wrinkle type and the tensile strain crack type, and improves the low-temperature impact service fatigue capacity of the component.

Description

Technical Field

[0001] This invention belongs to the field of stamping technology, specifically relating to a progressive die and stamping method for low-temperature impact-resistant multi-pressure curved stainless steel components. Background Technology

[0002] Stainless steel components are widely used in low-temperature operating conditions due to their excellent corrosion resistance and mechanical properties. The stamping quality of multi-bend stainless steel components directly determines their low-temperature service performance. (See also...) Figure 1 and Figure 2 As shown, in the prior art, the bending process of stainless steel plate 3 involves direct bending by the cooperation of punch 1 and die 2. The surfaces of concave arc 401 and convex arc 402 of part 4 are suspended and randomly deformed. The deformation process is completely uncontrollable, resulting in extremely unstable forming quality.

[0003] Due to uncontrollable deformation, compressive strain wrinkles and cracks easily form at the concave arcs of parts, accompanied by localized microscopic martensitic transformations; tensile strain tearing lines easily form on the convex arc surfaces of parts, also accompanied by localized microscopic martensitic transformations. These microstructural defects severely reduce the fatigue life of stainless steel components under low-temperature impact conditions, failing to meet the requirements of low-temperature equipment for multi-bending stainless steel components. Therefore, there is an urgent need for a stamping die and method that can achieve controllable bending deformation of stainless steel components and avoid microscopic martensitic transformations. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a progressive die and stamping method for low-temperature impact-resistant multi-bending stainless steel components. This method enables full control over the bending deformation of multi-bending stainless steel components, effectively preventing localized microscopic martensitic phase transformations such as compressive strain wrinkling and tensile strain cracking, and improving the low-temperature impact fatigue resistance of the components.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This invention provides a progressive die for low-temperature impact resistant multi-pressure curved stainless steel components, including a base and a blanking die and a blanking die disposed on the base. It also includes a second progressive double-bending unit and a third progressive bending unit disposed between the blanking die and the blanking die. The stainless steel progressive die plate passes through the blanking die, the second progressive double-bending unit, the third progressive bending unit and the blanking die in a stepping direction to complete the blanking, double-sided blanking, double-sided bending and blanking processes in sequence to obtain multi-pressure curved stainless steel components.

[0007] The second-stage double-bending unit includes a support frame, a lifting column, a return spring, a swing rod, a shaped pressure plate, a swinging curved pressure plate, and a bending fixture. The support frame and the bending fixture are both mounted on the base. The upper end of the shaped pressure plate is fixedly connected to the support frame, and the lower end is rotatably mounted with two swinging curved pressure plates. The rotation axis of the swinging curved pressure plates is parallel to the stepping direction of the stainless steel progressive die plate. The lifting column can be slidably mounted on the top of the support frame in the vertical direction, and the lifting column is connected to the support frame through a return spring. The bottom of the lifting column is hinged to the upper end of the two swing rods, and the lower end of the two swing rods is hinged to the two swinging curved pressure plates respectively. The two swinging curved pressure plates are located on both sides above the bending fixture. The two swinging curved pressure plates swing downward and cooperate with the bending fixture to realize the second-stage double-bending process at the root of the punching area of ​​the stainless steel progressive die plate, obtaining the bent arc segment at the root of the punching area.

[0008] The bending fixture includes a fixture base and a fixture head disposed on the upper end of the fixture base; the working surface of the fixture head includes a top surface of the bending fixture, a bottom surface of the bending fixture, and two curved sections located between the top surface and the bottom surface of the bending fixture, and each curved section includes an upper fillet, a side surface, and a lower fillet.

[0009] The working surface of the swinging curved pressure plate is a multi-curved surface structure composed of a first arc segment, a second arc segment, and a third arc segment. The second arc segment is adapted to the contour curve of the upper rounded corner of the tooling head, and the third arc segment is adapted to the contour line of the side curved surface of the tooling head.

[0010] The third-stage bending unit includes a left-side bending module and a right-side bending module arranged sequentially along the stepping direction of the stainless steel progressive die plate.

[0011] The left and right bending modules have the same structure, both including a hook-shaped component, a pressure block, a bending pressure plate, and a bending head. The hook-shaped component and the pressure block are arranged opposite each other. The hook-shaped component has a two-dimensional degree of freedom of movement in the horizontal direction, and the pressure block has a degree of freedom of movement in the direction of approaching or moving away from the hook-shaped component. The hook-shaped component and the pressure block cooperate to clamp and position the bending arc segment of the punching area of ​​the stainless steel progressive die material plate. The bending pressure plate has a three-dimensional degree of freedom of movement and rotation. The pressure block is set on the bending pressure plate and has a degree of freedom of movement relative to the bending pressure plate. The pressure block and the bending pressure plate cooperate to clamp the end straight segment of the punching area of ​​the stainless steel progressive die material plate, and the bending pressure plate couples the movement to bend the end straight segment.

[0012] The working surfaces of the hook-shaped component and the pressure block are compatible curved surface structures.

[0013] The working surface of the bending head includes a fixed area and a top arc area, wherein the fixed area cooperates with the bending pressure plate to clamp the end straight section; the top arc area is used to form the deformation bending section area between the pressure arc section and the end straight section.

[0014] The left bending module and the right bending module also include a drive component;

[0015] The drive assembly includes a transverse linear module I, a ground rail, a column, a transverse linear module II, a lifting linear module, a lifting block, a transverse linear module III, and a rotary drive module. The transverse linear module I and the ground rail are mounted on the base. The transverse linear module I outputs power along a stepping direction perpendicular to the stainless steel progressive die plate, and its output end is connected to the pressure block. The ground rail contains two sets of longitudinal linear modules I and II, both outputting power along a stepping direction parallel to the stainless steel progressive die plate. The output end of the longitudinal linear module I is connected to the column. The upper end of the column is provided with a horizontal straight module II parallel to the horizontal straight module I, and the output end of the horizontal straight module II is connected to the hook-shaped component; the output end of the vertical straight module II is connected to the lifting straight module, the output end of the lifting straight module is connected to the lifting block, and a horizontal straight module III parallel to the horizontal straight module I is installed on the lifting block. The output end of the horizontal straight module III is connected to the rotary drive module, and the output end of the rotary drive module is connected to the bending head. The rotary drive module is used to drive the bending head to rotate, and the rotation axis of the bending head is parallel to the stepping direction of the stainless steel progressive die plate.

[0016] Another aspect of the present invention provides a stamping method based on the progressive die for low-temperature impact-resistant multi-pressure curved stainless steel components as described above, comprising the following steps:

[0017] Step S1, First process punching: Two C-shaped plates are punched out of the stainless steel progressive die plate using a punching die to prepare for the subsequent double punching process;

[0018] Step S2, Second-stage double punching: The punching area of ​​the stainless steel progressive die plate supported by the bending tool is compacted by the irregular pressure plate; the lifting column drives the swing rod to move, so that the swing curved pressure plate swings in a controllable trajectory. The swing curved pressure plate uses the multi-curved surface structure working surface to cooperate with the bending tool to punch out the pressed curved section at the root of the punching area.

[0019] Step S3, Third-stage side bending: First, the hook-shaped part and pressure block in the second-stage double-bending unit are used to clamp the curved section on one side of the punching area; then, the bending pressure plate and bending head are used to clamp the straight section at the end of the punching area; and then, the bending of the straight section at the end is achieved through the coupled movement of the bending head.

[0020] Step S4, Fourth stage bending on the other side: Using the same bending process as in step S3, bend and shape the other side of the punching area;

[0021] Step S5, Fifth Progressive Workpiece Single Punch-Off: The formed stainless steel component is punched off the stainless steel progressive die plate using a punching die to complete the overall stamping process.

[0022] In step S3, the coupled motion of the bending head is a coupling of three-dimensional planar motion and rotational motion, which realizes the gradual fit between the top arc area of ​​the bending head and the deformed bending section area, thus avoiding local stress concentration.

[0023] The present invention has the following beneficial effects and advantages:

[0024] 1. This invention designs a five-stage progressive stamping process, which decomposes the forming of multi-bend stainless steel components into punching, double punching, double-sided bending, and finished product punching, realizing step-by-step controllable forming of complex bending structures and solving the problem of suspended random deformation in the prior art.

[0025] 2. In the double-bending process of the present invention, the coordinated cooperation of the irregular pressure plate, the swing curved surface pressure plate and the bending tooling makes the bending arc segment in a biaxial compressive strain plastic state, and realizes the controllable strain gradual transformation along the specified direction. The plastic strain is less than the material's ultimate strength, effectively preventing local microscopic martensitic phase transformation of compressive strain wrinkling cracks and tensile strain tearing.

[0026] 3. The bending process of the present invention adopts a multi-degree-of-freedom hook-shaped component, pressure block, and bending head structure, which realizes the flexible fixing and gradual bending of the material plate, avoids local stress concentration, and further ensures the controllability of deformation.

[0027] 4. The multi-bend stainless steel components formed by the mold and method of the present invention eliminate microstructural defects under low-temperature impact conditions, significantly improve the low-temperature service fatigue life of the components, and meet the usage requirements of low-temperature equipment;

[0028] 5. The shape design of the bending tooling of the present invention is adapted to the stamping springback characteristics of thin-walled stainless steel. It can be optimized through existing technologies such as finite element simulation and experimental design, and has good versatility and adaptability. It can be widely applied to the stamping of multi-bend stainless steel components of different specifications.

[0029] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0030] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0031] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0032] Figure 1 This is a schematic diagram of the structure of a stainless steel plate before it is suspended and deformed using existing technology.

[0033] Figure 2 This is a schematic diagram of the structure of a stainless steel plate after it has been suspended and deformed using existing technology.

[0034] Figure 3 This is an isometric view of a progressive die for a low-temperature impact-resistant, multi-pressure curved stainless steel component according to the present invention.

[0035] Figure 4 for Figure 3 AA section view;

[0036] Figure 5 for Figure 4 Enlarged view of a section at point I;

[0037] Figure 6 This is a schematic diagram of the working state of the oscillating curved pressure plate in this invention;

[0038] Figure 7 for Figure 3 BB section view;

[0039] Figure 8 This is a schematic diagram of the working state of the second-stage double-bending unit in this invention;

[0040] Figure 9 for Figure 8 Enlarged view of section II in the middle;

[0041] Figure 10 This is a schematic diagram of the working state of the third-stage bending unit before bending in this invention.

[0042] Figure 11 This is a schematic diagram of the working state of the third-stage bending unit after bending in this invention.

[0043] Figure 12 This is one of the isometric views of the driving component in this invention;

[0044] Figure 13 This is the second isometric view of the driving component in this invention;

[0045] Figure 14 This is a front view of the progressive processing layout of the stainless steel progressive die plate in this invention.

[0046] Figure 15 This is a schematic diagram of the back side of the progressive processing layout of the stainless steel progressive die plate in this invention.

[0047] In the diagram: 1. Punch; 2. Die; 3. Stainless steel plate; 4. Part; 401. Concave arc; 402. Convex arc; 5. Stainless steel progressive die plate; 501. First punching operation; 502. Second progressive double punching; 503. Third progressive one-sided bending; 504. Fourth progressive other-sided bending; 505. Fifth progressive single punching operation; 506. Folded flat section; 507. First bending arc section; 508. Second bending arc section; 509. Deformation bending section area; 510. End straight section; 511. Bending arc section; 6. Hook-shaped part; 7. Pressure block; 8. Bending pressure plate; 9. Bending head; 901. Fixing area; 902. Top arc area; 10. Punching die; 11. Support frame ; 12. Base; 13. Lifting column; 14. Return spring; 15. Swing rod; 17. Irregularly shaped pressure plate; 18. Swinging curved pressure plate; 1801. First axis; 1802. First arc segment; 1803. Second arc segment; 1804. Third arc segment; 1805. Second axis; 19. Bending fixture; 1901. Top surface of bending fixture; 1902. Upper fillet; 1903. Side curved surface; 1904. Lower fillet; 1905. Bottom surface of bending fixture; 20. Horizontal straight module I; 21. Ground rail; 22. Column; 23. Horizontal straight module II; 24. Lifting straight module; 25. Lifting block; 26. Horizontal straight module III; 27. Rotation drive module. Detailed Implementation

[0048] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0049] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0050] See Figures 3 to 15As shown, one embodiment of the present invention provides a progressive die for low-temperature impact-resistant multi-pressure curved stainless steel components, including a base 12 and a blanking die 10 and a blanking mold disposed on the base 12. It also includes a second progressive double-bending unit and a third progressive bending unit sequentially disposed between the blanking die 10 and the blanking mold. The stainless steel progressive die plate 5 passes along the stepping direction through the blanking die 10, the second progressive double-bending unit, the third progressive bending unit, and the blanking mold, sequentially completing the first process of punching down 501, the second progressive double-bending 502, the third progressive one-sided bending 503, the fourth progressive other-sided bending 504, and the fifth progressive single punching down 505, ultimately obtaining a multi-pressure curved stainless steel component. The first process, punching down 501, punches down two C-shaped plates from the stainless steel progressive die plate 5, preparing for the subsequent process, the second progressive double-bending 502.

[0051] See Figure 7 As shown, the multi-curved stainless steel component finally obtained by the present invention includes a flat section 506, a curved section 511, a deformed bending section area 509, and a straight end section 510. The curved section 511 includes a first curved section 507 and a second curved section 508, and the first curved section 507 and the second curved section 508 are a convex arc surface and a concave arc surface, respectively, with smooth transitions between each section.

[0052] See Figures 3 to 9 As shown, in an embodiment of the present invention, the second progressive double-bending unit includes a support frame 11, a lifting column 13, a return spring 14, a swing rod 15, a shaped pressure plate 17, a swinging curved surface pressure plate 18, and a bending fixture 19. The support frame 11 and the bending fixture 19 are both mounted on the base 12. The upper end of the shaped pressure plate 17 is fixedly connected to the support frame 11, and the lower end is rotatably mounted with two swinging curved surface pressure plates 18 via two first shafts 1801. The rotation axis of the swinging curved surface pressure plates 18 is parallel to the stepping direction of the stainless steel progressive die plate 5. The lifting column 13 can be slidably mounted on the top of the support frame 11 in the vertical direction, and... The lifting column 13 is connected to the support frame 11 via a return spring 14; the bottom of the lifting column 13 is hinged to the upper ends of the two swing rods 15, the upper ends of the swing rods 15 and the lifting column 13 form a rotating pair and are maintained in a stable state by a torsion spring; the lower ends of the two swing rods 15 are respectively hinged to the two swing curved surface pressure plates 18 via the second shaft 1805, the two swing curved surface pressure plates 18 are located on both sides above the bending fixture 19, the two swing curved surface pressure plates 18 swing downward and cooperate with the bending fixture 19 to realize the second progressive double punching process at the root of the punching area of ​​the stainless steel progressive die plate 5, and obtain the bent arc segment 511 at the root of the punching area.

[0053] In an embodiment of the present invention, the bending fixture 19 includes a fixture base and a fixture head disposed on the upper end of the fixture base; the working surface of the fixture head includes a top surface 1901, a bottom surface 1905, and two curved segments located between the top surface 1901 and the bottom surface 1905 of the bending fixture, each curved segment including an upper fillet 1902, a side curved surface 1903, and a lower fillet 1904. The working surface of the swing curved pressure plate 18 is a multi-curved surface structure composed of a first curved segment 1802, a second curved segment 1803, and a third curved segment 1804, wherein the second curved segment 1803 is adapted to the contour curve of the upper fillet 1902 of the fixture head, and the third curved segment 1804 is adapted to the contour line of the side curved surface 1903 of the fixture head.

[0054] Specifically, the bending fixture 19 is a slightly smaller structure that matches the concave shape of the bending arc segment 511 of the stainless steel progressive die plate 5, adapting to the stamping springback characteristics of thin-walled stainless steel. The specific shape can be determined through finite element simulation, experimental design, or empirical mold modification. The bending fixture 19 includes a top surface 1901, an upper fillet 1902, a side curved surface 1903, and a lower fillet 1904; the swinging curved pressure plate 18 is provided with a first arc segment 1802, a second arc segment 1803, and a third arc segment 1804. During operation, the irregularly shaped pressure plate 17 lowers and compacts the top surface 1901 of the curved tooling and the folded plane section 506 of the stainless steel progressive die material plate 5 to prevent the material plate from shifting during the stamping process. The lifting column 13 drives the swing rod 15 to move, causing the swinging curved pressure plate 18 to swing around the first axis 1801 in a controllable trajectory. The first arc section 1802 of the swinging curved pressure plate 18 forms a small gap with the top surface 1901 of the curved tooling for frictionless relative motion. The second arc section 1803 is adapted to the upper fillet 1902 of the curved tooling 19 to stamp the first curved section 507. The third arc section 1804 is adapted to the side curved surface 1903 of the curved tooling 19 to stamp the second curved section 508. Both the first and second curved sections achieve controllable strain gradual shaping in a biaxial compressive strain plastic state along the direction away from the first axis 1801 of the swinging curved pressure plate 18. See [link to relevant documentation]. Figure 5 and Figure 6 As shown, the plastic strain is guaranteed to be less than the material's ultimate strength.

[0055] See Figure 10 and Figure 11As shown, in an embodiment of the present invention, the third progressive bending unit includes a left bending module and a right bending module arranged sequentially along the stepping direction of the stainless steel progressive die plate 5, and the left bending module and the right bending module are arranged left and right. The left bending module and the right bending module have the same structure, both including a hook-shaped part 6, a pressure block 7, a bending pressure plate 8 and a bending head 9. The hook-shaped part 6 and the pressure block 7 are arranged opposite to each other. The hook-shaped part 6 has a two-dimensional degree of freedom of movement in the horizontal direction, and the pressure block 7 has a degree of freedom of movement in the direction of moving closer to or away from the hook-shaped part 6. The hook-shaped part 6 and the pressure block 7 cooperate to clamp and position the bending arc segment 511 of the punching area of ​​the stainless steel progressive die plate 5. The bending pressure plate 8 has a three-dimensional degree of freedom of movement and rotation. The pressure block 7 is set on the bending pressure plate 8 and has a degree of freedom of movement relative to the bending pressure plate 8. The pressure block 7 and the bending pressure plate 8 cooperate to clamp the end straight segment 510 of the punching area of ​​the stainless steel progressive die plate 5. The bending pressure plate 8 couples the movement to bend the end straight segment 510.

[0056] Furthermore, the working surfaces of the hook-shaped component 6 and the pressure block 7 are adapted curved surface structures. The working surface of the bending head 9 includes a fixed area 901 and a top arc area 902, wherein the fixed area 901 cooperates with the bending pressure plate 8 to clamp the end straight section 510; the top arc area 902 is used to form the deformable bending section area 509 between the bending arc section 511 and the end straight section 510.

[0057] See Figure 12 and Figure 13 As shown, in the embodiment of the present invention, the left bending module and the right bending module further include a driving assembly; the driving assembly includes a transverse linear module I 20, a ground rail 21, a column 22, a transverse linear module II 23, a lifting linear module 24, a lifting block 25, a transverse linear module III 26, and a rotary driving module 27, wherein the transverse linear module I 20 and the ground rail 21 are disposed on the base 12, the transverse linear module I 20 outputs power along the stepping direction perpendicular to the stainless steel progressive die plate 5, and the output end of the transverse linear module I 20 is connected to the pressure block 7; the ground rail 21 is provided with two sets of longitudinal linear modules I and longitudinal linear modules II, both of which output power along the stepping direction parallel to the stainless steel progressive die plate 5, wherein the longitudinal linear module I outputs power along the stepping direction parallel to the stainless steel progressive die plate 5, wherein the longitudinal linear module II outputs power along the stepping direction parallel to the stainless steel progressive die plate 5, and the vertical linear module II outputs power along the stepping direction parallel to the stainless steel progressive die plate 5. The output end of line module I is connected to column 22. The upper end of column 22 is provided with a horizontal straight module II 23 parallel to the horizontal straight module I 20. The output end of horizontal straight module II 23 is connected to hook-shaped part 6. The output end of vertical straight module II is connected to lifting straight module 24. The output end of lifting straight module 24 is connected to lifting block 25. A horizontal straight module III 26 parallel to the horizontal straight module I 20 is installed on lifting block 25. The output end of horizontal straight module III 26 is connected to rotary drive module 27. The output end of rotary drive module 27 is connected to bending head 9. Rotary drive module 27 is used to drive bending head 9 to rotate. The rotation axis of bending head 9 is parallel to the stepping direction of stainless steel progressive die plate 5.

[0058] Specifically, the transverse linear module I 20, transverse linear module II 23, lifting linear module 24, transverse linear module III 26, longitudinal linear module I, and longitudinal linear module II all employ hydraulic drives consisting of hydraulic cylinders and slide rails, or any existing mechanism for achieving linear motion, without specific limitations. The rotary drive module 27 employs a rotary drive consisting of a hydraulic motor and a planetary reducer, or any existing drive mechanism for achieving rotary function, without specific limitations.

[0059] During operation, the hook-shaped part 6 presses down on the inner wall of the bending arc section 511, and the pressure block 7 presses down on the outer wall of the bending arc section 511 to fix the material plate; the bending pressure plate 8 presses the end straight section 510 of the punching area onto the fixed area 901 of the bending head 9, first causing tensile strain inside the deformed bending section area 509, and then through the four-degree-of-freedom coupled motion of the bending head 9, the top arc area 902 of the bending head 9 gradually fits into the deformed bending section area 509 to achieve bending and forming, avoiding local stress concentration.

[0060] Specifically, the fifth progressive workpiece single punch 505 uses existing punching technology to punch the formed stainless steel component off the stainless steel progressive die plate 5 to complete the overall stamping forming.

[0061] This invention provides a low-temperature impact-resistant progressive die for multi-pressure bending stainless steel components. Addressing the problems of uncontrollable deformation, easy martensitic transformation, and low low-temperature fatigue life in existing stainless steel bending processes, the stainless steel progressive die plate 5 employs a five-segment progressive stamping process. The stamping steps of the stainless steel progressive die plate 5 include: a first step of punching down 501, a second step of progressive double punching and bending 502, a third step of progressive bending on one side 503, a fourth step of progressive bending on the other side 504, and a fifth step of progressive single punching down 505. (See also...) Figure 14 and Figure 15 As shown, the double-bending process incorporates controllable forming structures such as an irregularly shaped pressure plate 17, a swinging curved surface pressure plate 18, and a bending fixture 19, allowing the bent arc segment 511 to be controlled and formed under biaxial compressive strain plasticity. The bending process utilizes multi-degree-of-freedom fixtures to achieve gradual conforming deformation. This invention achieves full control over the compressive bending deformation of stainless steel components, effectively avoiding localized microscopic martensitic phase transformations such as compressive strain wrinkling cracks and tensile strain tearing, and significantly improving the low-temperature impact fatigue life of multi-bend stainless steel components.

[0062] See Figures 3 to 15 As shown, another embodiment of the present invention provides a stamping method based on the low-temperature impact-resistant multi-pressure curved stainless steel component progressive die as described above, comprising the following steps:

[0063] Step S1, First process punching: Two C-shaped plates are punched off the stainless steel progressive die plate 5 using the punching die 10 to prepare for the subsequent double punching process;

[0064] Step S2, Second-stage double punching: The punching area of ​​the stainless steel progressive die plate 5 supported by the bending fixture 19 is pressed by the irregular pressure plate 17; the lifting column 13 drives the swing rod 15 to move, so that the swing curved pressure plate 18 swings in a controllable trajectory. The swing curved pressure plate 18 uses the multi-curved surface structure working surface to cooperate with the bending fixture 19 to punch out the pressed curved section 511 at the root of the punching area.

[0065] Step S3, Third-stage side bending: First, the hook-shaped part 6 and the pressure block 7 in the second-stage double punching unit are used to clamp the bent arc segment 511 on one side of the punching area; then, the bending pressure plate 8 and the bending head 9 are used to clamp the end straight segment 510 of the punching area; then, the bending of the end straight segment 510 is achieved through the coupled movement of the bending head 9.

[0066] Step S4, Fourth stage bending on the other side: Using the same bending process as in step S3, bend and shape the other side of the punching area;

[0067] Step S5, Fifth Progressive Workpiece Single Punch-Off: The formed stainless steel component is punched off the stainless steel progressive die plate 5 using a punching die to complete the overall stamping process.

[0068] In step S3, the coupled motion of the bending head 9 is a coupling of three-dimensional planar motion and rotational motion, so as to achieve the gradual fit between the top arc area 902 of the bending head 9 and the deformed bending section area 509, thereby avoiding local stress concentration.

[0069] In step S2, the convex and concave arc surfaces of the first bending arc segment 507 and the second bending arc segment 508 are both subjected to biaxial compressive strain plastic forming, and no local microscopic martensitic phase transformations such as compressive strain wrinkles and cracks or tensile strain tears are generated.

[0070] This invention enables full control over the bending deformation of multi-bend stainless steel components, effectively preventing local microscopic martensitic phase transformations of compressive strain wrinkling and tensile strain cracking, and improving the low-temperature impact fatigue resistance of the components.

[0071] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A progressive die for low-temperature impact-resistant multi-pressure bending stainless steel components, comprising a base (12) and a blanking die (10) and a punching die disposed on the base (12), characterized in that, It also includes a second-stage double-bending unit and a third-stage bending unit arranged sequentially between the blanking die (10) and the stamping die. The stainless steel progressive die plate (5) passes through the blanking die (10), the second-stage double-bending unit, the third-stage bending unit and the stamping die in sequence to complete the blanking, double-sided bending, double-sided bending and stamping processes, thereby obtaining a multi-pressed curved stainless steel component.

2. The progressive die for low-temperature impact-resistant multi-pressure bending stainless steel components according to claim 1, characterized in that, The second progressive double-bending unit includes a support frame (11), a lifting column (13), a return spring (14), a swing rod (15), a shaped pressure plate (17), a swing curved surface pressure plate (18), and a bending fixture (19). The support frame (11) and the bending fixture (19) are both mounted on the base (12). The upper end of the shaped pressure plate (17) is fixedly connected to the support frame (11), and the lower end is rotatably mounted with two swing curved surface pressure plates (18). The rotation axis of the swing curved surface pressure plates (18) is parallel to the stepping direction of the stainless steel progressive die plate (5). The lifting column (13) can be slidably mounted in the vertical direction. At the top of the support frame (11), the lifting column (13) is connected to the support frame (11) through the return spring (14). The bottom of the lifting column (13) is hinged to the upper end of the two swing rods (15). The lower end of the two swing rods (15) is hinged to the two swing curved pressure plates (18) respectively. The two swing curved pressure plates (18) are located on both sides above the bending fixture (19). The two swing curved pressure plates (18) swing downward and cooperate with the bending fixture (19) to realize the second progressive double punching process at the root of the punching area of ​​the stainless steel progressive die plate (5), and obtain the bent arc segment (511) at the root of the punching area.

3. The progressive die for low-temperature impact-resistant multi-pressure bending stainless steel components according to claim 2, characterized in that, The bending fixture (19) includes a fixture base and a fixture head disposed on the upper end of the fixture base; the working surface of the fixture head includes a top surface (1901) of the bending fixture, a bottom surface (1905) of the bending fixture, and two curved sections located between the top surface (1901) and the bottom surface (1905) of the bending fixture. Each curved section includes an upper fillet (1902), a side curved surface (1903), and a lower fillet (1904).

4. The progressive die for low-temperature impact-resistant multi-pressure bending stainless steel components according to claim 3, characterized in that, The working surface of the swing curved pressure plate (18) is a multi-curved surface structure composed of a first arc segment (1802), a second arc segment (1803) and a third arc segment (1804). The second arc segment (1803) is adapted to the contour curve of the upper fillet (1902) of the tooling head, and the third arc segment (1804) is adapted to the contour line of the side curved surface (1903) of the tooling head.

5. The progressive die for low-temperature impact-resistant multi-pressure bending stainless steel components according to claim 2, characterized in that, The third progressive bending unit includes a left bending module and a right bending module arranged sequentially along the stepping direction of the stainless steel progressive die plate (5); The left and right bending modules have the same structure, both including a hook-shaped part (6), a pressure block (7), a bending pressure plate (8), and a bending head (9). The hook-shaped part (6) and the pressure block (7) are arranged opposite to each other. The hook-shaped part (6) has a two-dimensional degree of freedom of movement in the horizontal direction, and the pressure block (7) has a degree of freedom of movement in the direction of moving closer to or away from the hook-shaped part (6). The hook-shaped part (6) and the pressure block (7) cooperate to clamp and position the bending arc segment (511) of the punching area of ​​the stainless steel progressive die plate (5). The bending pressure plate (8) has a three-dimensional degree of freedom of movement and rotation. The pressure block (7) is set on the bending pressure plate (8) and has a degree of freedom of movement relative to the bending pressure plate (8). The pressure block (7) and the bending pressure plate (8) cooperate to clamp the end straight segment (510) of the punching area of ​​the stainless steel progressive die plate (5). The bending pressure plate (8) couples the movement to bend the end straight segment (510).

6. The progressive die for low-temperature impact-resistant multi-pressure bending stainless steel components according to claim 5, characterized in that, The working surfaces of the hook-shaped component (6) and the pressure block (7) are compatible curved surface structures.

7. The progressive die for low-temperature impact-resistant multi-pressure curved stainless steel components according to claim 5, characterized in that, The working surface of the bending head (9) includes a fixed area (901) and a top arc area (902), wherein the fixed area (901) cooperates with the bending pressure plate (8) to clamp the end straight section (510); the top arc area (902) is used to form the deformation bending section area (509) between the bending arc section (511) and the end straight section (510).

8. The progressive die for low-temperature impact-resistant multi-pressure curved stainless steel components according to claim 5, characterized in that, The left bending module and the right bending module also include a drive component; The drive assembly includes a transverse linear module I (20), a ground rail (21), a column (22), a transverse linear module II (23), a lifting linear module (24), a lifting block (25), a transverse linear module III (26), and a rotary drive module (27). The transverse linear module I (20) and the ground rail (21) are mounted on the base (12). The transverse linear module I (20) outputs power along a stepping direction perpendicular to the stainless steel progressive die plate (5), and the output end of the transverse linear module I (20) is connected to the pressure block (7). The ground rail (21) contains two sets of longitudinal linear modules I and II, both outputting power along a stepping direction parallel to the stainless steel progressive die plate (5). The output end of the longitudinal linear module I is connected to the column (22). The upper end of the column (22) is provided with a horizontal straight module II (23) parallel to the horizontal straight module I (20), and the output end of the horizontal straight module II (23) is connected to the hook-shaped part (6); the output end of the vertical straight module II is connected to the lifting straight module (24), the output end of the lifting straight module (24) is connected to the lifting block (25), and a horizontal straight module III (26) parallel to the horizontal straight module I (20) is installed on the lifting block (25). The output end of the horizontal straight module III (26) is connected to the rotary drive module (27), and the output end of the rotary drive module (27) is connected to the bending head (9). The rotary drive module (27) is used to drive the bending head (9) to rotate, and the rotation axis of the bending head (9) is parallel to the stepping direction of the stainless steel progressive die plate (5).

9. A stamping method based on the progressive die for low-temperature impact-resistant multi-pressure curved stainless steel components as described in claim 7, characterized in that, Includes the following steps: Step S1, First process punching: Two C-shaped plates are punched off the stainless steel progressive die plate (5) using the punching die (10) to prepare for the subsequent double punching process; Step S2, Second-stage double punching: The punching area of ​​the stainless steel progressive die plate (5) supported by the bending fixture (19) is compacted by the irregular pressure plate (17); the lifting column (13) drives the swing rod (15) to move, so that the swing curved pressure plate (18) swings in a controllable trajectory. The swing curved pressure plate (18) uses the multi-curved surface structure working surface to cooperate with the bending fixture (19) to punch out the pressed curved section (511) at the root of the punching area. Step S3, Third-stage side bending: First, the hook-shaped part (6) and the pressure block (7) in the second-stage double-bending unit are used to clamp the bending arc segment (511) on one side of the punching area; then, the bending pressure plate (8) and the bending head (9) are used to clamp the end straight segment (510) of the punching area; and then, the bending of the end straight segment (510) is achieved by the coupling movement of the bending head (9). Step S4, Fourth stage bending on the other side: Using the same bending process as in step S3, bend and shape the other side of the punching area; Step S5, fifth progressive workpiece single punching: The formed stainless steel component is punched off the stainless steel progressive die plate (5) through the punching die to complete the overall stamping.

10. The stamping method according to claim 9, characterized in that, In step S3, the coupled motion of the bending head (9) is a coupling of three-dimensional planar motion and rotational motion, so as to achieve the gradual fit between the top arc area (902) of the bending head (9) and the deformed bending section area (509) and avoid local stress concentration.

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