Brake shoe bolt preparation mold and preparation process thereof

Abstract

The invention discloses a brake shoe bolt preparation mold and a preparation process thereof, and belongs to the technical field of brake shoe bolt preparation processes, the brake shoe bolt preparation mold is characterized in that a blanking mold comprises a blanking upper mold plate and a blanking lower mold plate, the blanking upper mold plate comprises a blanking upper bottom plate, a cutter and a pressing block, the blanking lower die plate comprises a blanking lower bottom plate, a material bearing block and a positioning mechanism, the pressing die comprises an upper pressing die plate and a lower pressing die plate, the upper pressing die plate comprises an upper pressing bottom plate, an upper die stretching punch and an upper corrugation die block, and the lower pressing die plate comprises a lower pressing bottom plate, a lower die concave block and a lower corrugation die plate. The bending die comprises an upper bending die plate and a lower bending die plate, the upper bending die plate comprises an upper bending die bottom plate, an upper bending die block and an upper die floating pre-pressing block, and the lower bending die plate comprises a lower bending die bottom plate, a lower bending die block and a lower die floating pre-pressing block. Compared with the prior art, the method has the characteristic of forming multi-bend appearance through one-time bending.

Description

Technical Field

[0001] The invention relates to the technical field of brake shoe latch preparation technology, in particular to a brake shoe latch preparation mould and a preparation technology thereof. Background Art

[0002] As an indispensable key component and consumable part in the train braking system, the brake shoe latch plays a vital role. It cleverly uses the preset slot design to significantly increase the friction between the brake shoe and the wheel contact surface, which is the basis for achieving effective braking. Furthermore, the anti-skid grooves carefully set on the surface of the latch can ensure that the brake shoe is tightly and stably interlocked with the wheel during emergency braking. This design greatly reduces the risk of the brake shoe falling off due to uneven force, thereby ensuring that at the moment of train braking, the gripping force between the brake shoe and the wheel is significantly improved, making the braking action faster and the braking effect more significant, ensuring the safety of train driving.

[0003] Given the important role of brake shoe pins in the braking process and the complex mechanical environment they face, they must have a considerable degree of hardness and toughness to resist the huge friction and impact forces generated during braking while maintaining structural integrity and stability. In order to achieve these performance requirements, brake shoe pins are usually made of high-quality spring steel, which is known for its excellent elastic recovery ability and good mechanical strength, and is an ideal choice for manufacturing parts that bear dynamic loads.

[0004] However, the manufacturing process of the brake shoe latch is not an easy task. The forging is uniquely designed with chamfers on both ends. It is not only long and thin, but also has a complex and varied shape, including multiple curved parts, as well as wavy patterns on the surface and stretching grooves with embossed characters. Although these design features enhance the functionality and durability of the latch, they also bring challenges to processing. Due to its complex shape and slender size, the brake shoe latch is very prone to bending and deformation during the forging process, which undoubtedly increases the difficulty of production.

[0005] The traditional direct forging method not only has low material utilization and causes waste of resources, but also due to the complex shape, it is often impossible to form it in one go and requires multiple processing and adjustments, which not only prolongs the production cycle and reduces production efficiency, but also increases manufacturing costs. Summary of the invention

[0006] The purpose of the present invention is to provide a brake shoe pin preparation mold and a preparation process thereof to achieve the purpose of one-time bending to form multiple curved appearances in view of the above shortcomings of the prior art.

[0007] The present invention provides a brake shoe latch preparation mold, comprising a blanking mold, a forming mold and a bending mold; the characteristic is that: the blanking mold comprises an upper blanking mold and a lower blanking mold, the upper blanking mold comprises an upper blanking bottom plate, a cutter and a pressure block, a pressure block is installed at the middle position of the lower end surface of the upper bottom plate, cutters are installed at both ends of the pressure block, and the upper end of the cutter is fixedly connected to the upper bottom plate; the lower blanking mold comprises a lower blanking bottom plate, a receiving block and a positioning mechanism, the upper end surface of the lower blanking bottom plate is installed with a receiving block, and the receiving block is fixedly connected to the upper bottom plate. The block is provided with a limiting cavity; the pressing mold comprises a pressing upper template and a pressing lower template, the pressing upper template comprises a pressing upper bottom plate, an upper die stretching punch and a corrugated upper module, the upper die stretching punch and the corrugated upper template are fixedly installed on the lower end surface of the pressing upper bottom plate, and the corrugated upper template has a wave-spinning cavity; the pressing lower template comprises a pressing lower bottom plate, a lower die concave block and a corrugated lower template, the lower die concave block has a stretching groove corresponding to the upper die stretching punch, the corrugated lower template has a wave-spinning cavity, and the corrugated lower template is corresponding to the cavity of the corrugated upper template Correspondingly; the bending mold includes a bending upper template and a bending lower template, the bending upper template includes a bending upper template bottom plate, a bending upper module and an upper mold floating pre-pressing block, the lower end surface of the bending upper template bottom plate is fixedly connected to the bending upper module, the lower end surface of the bending upper module is a bending surface, the rear end of the bending upper module is provided with a guide cavity with a lower end opening, the upper mold floating pre-pressing block is placed in the guide cavity of the bending upper module, the lower end of the upper mold floating pre-pressing block is a wavy-shaped cavity, the wavy-shaped cavity of the upper mold floating pre-pressing block and the wavy-shaped cavity of the corrugated upper template Correspondingly; the bending lower template includes a bending lower template base plate, a bending lower module and a lower template floating pre-pressure block. The upper end surface of the bending lower template base plate is fixedly connected to the bending lower module. The front end of the bending lower module is provided with a guide cavity with an upper end opening. The lower template floating pre-pressure block is placed in the guide cavity of the bending upper module. The upper end of the lower template floating pre-pressure block is rotatably connected to the roller. The front end part of the upper end surface of the bending lower module is a bending surface, and the rear end part is a wave-spinning cavity. The wave-spinning cavity of the bending lower module corresponds to the wave-spinning cavity of the corrugated lower template.

[0008] Furthermore, the blanking upper base plate is connected to the pressing block through a pressing plate, and the blanking upper base plate and the pressing plate are connected by bolts. A spring is sleeved on the outer side of the bolt, and the upper end of the spring is connected to the blanking upper base plate, and the lower end is connected to the pressing plate.

[0009] Furthermore, the positioning mechanism is arranged at one end of the slot of the receiving block, and the positioning mechanism includes a floating positioning block, a spring and a guide pin; the guide pin is fixedly installed on the lower bottom plate of the blanking material, and the floating positioning block is provided with a guide through hole. The guide through hole of the floating positioning block slides up and down with the guide pin, and a spring is sleeved on the outer side of the guide pin. The upper end of the spring is connected to the floating positioning block, and the lower end of the floating positioning block is connected to the lower bottom plate of the blanking material.

[0010] Furthermore, the upper die stretching punch is in a step shape, and its boss is installed on the pressing upper base plate.

[0011] Furthermore, the lower end of the press-formed upper base plate is connected to the upper mold block by bolts, a spring is sleeved on the outer side of the bolt, the upper end of the spring is fixedly connected to the press-formed upper base plate, and the lower end is fixedly connected to the upper mold block, a through hole is provided on the upper mold block, and the upper mold stretching punch passes through the through hole of the upper mold block.

[0012] Furthermore, a lower mold positioning block is installed at one end of the corrugated lower mold block.

[0013] Furthermore, the lower end of the press-formed lower base plate is connected to the lower mold block by bolts, a spring is sleeved on the outer side of the bolt, the upper end of the spring is fixedly connected to the press-formed lower base plate, and the lower end is fixedly connected to the lower mold block. The lower mold block is provided with a through hole, and the lower mold concave block and the corrugated lower mold plate respectively pass through the through holes of the lower mold block.

[0014] A brake shoe latch preparation process based on the above mold is characterized by comprising the following steps: ① Material heating; The long bar is heated in sections, and goes through four stages: preheating, heating, equalizing temperature, and keeping warm. ② Phosphorus removal treatment; Use a dephosphorization machine to remove the oxide scale on the surface of the long bar, which is beneficial to maintain the surface quality of subsequent processing; ③ Rolling billets; During rolling, the long bar is roughly rolled to a thickness of 6±0.25 mm and a width of 18 mm±0.5 mm, then finely rolled to a thickness of 5.2±0.15 mm and a width of 21.8 mm±0.1 mm, and finally shaped to a long billet of 5±0.1 mm in thickness and 22 mm±0.1 mm in width; ④Blanking; Cut a single long billet and chamfer C8 on both ends of the long billet; place the long billet in the limiting cavity of the receiving block and position it with the floating positioning block at the front end; place the long billet in the limiting cavity of the receiving block and position it with the initial positioning surface of the floating positioning block at the front end to complete the initial positioning; the upper blank template moves downward, the pressure block presses the long billet, and the cutter cuts off the first small billet from both ends of the receiving block; the upper blank template moves upward, driving the pressure block and the cutter upward to take out the first small billet; the long billet with the small billet cut off is placed in the limiting cavity of the receiving block and positioned on the subsequent positioning surface of the floating positioning block to complete the secondary positioning; the upper blank template moves downward, the pressure block presses the long billet, and the cutter cuts off the second small billet from both ends of the receiving block; the upper blank template moves upward, driving the pressure block and the cutter upward to take out the second small billet; subsequently, the blanks are cut out in sequence according to the positioning method of the second small billet until the cutting is completed.

[0015] ⑤ Pressing; The small blank is placed between the stretching groove of the lower die concave block and the lower die positioning block to complete the initial positioning; the upper die plate moves downward, the upper die stretching punch presses the long blank, the upper die stretching punch cooperates with the stretching groove of the lower die concave block to stretch out the workpiece boss and extrude the convex mark; at the same time, the corrugated upper die block and the corrugated lower die block extrude the corrugated pattern of the workpiece; the upper die plate moves upward to take out the workpiece after the press; ⑥Bending; The small blank after forming is positioned according to the corrugated end and placed on the limiting groove of the bending lower module; the small blank is lifted horizontally by the roller of the floating pre-pressing block of the lower die; the bending upper template moves downward, and the floating pre-pressing block of the upper die first pre-presses the corrugated surface of the small blank, and at the same time, the floating pre-pressing block of the lower die starts to move downward; the bending upper template continues to move downward, the bending upper module contacts and gradually compacts the small blank, and at the same time drives the floating pre-pressing block of the lower die to continue to move downward, and the small blank is pulled by the roller of the floating pre-pressing block of the lower die and bent and deformed downward until the bending upper module and the bending lower module are relatively closed, and finally the blank is formed, the bending upper template moves upward, and the floating pre-pressing block of the lower die removes the formed workpiece from the die; ⑦ After the forming process is completed, the temperature is automatically sorted. If it is greater than or equal to 860℃, it will enter the heating and insulation line; otherwise, it will enter the heating and insulation line and then enter the crawler quenching and tempering line after reaching the design temperature; the tempering temperature is 460℃±5℃, and the tempering time is 120±15 min; the hardness after heat treatment reaches HRC44~52; the metallographic structure is better than level 4.

[0016] ⑧ Shot blasting; Choose sand-less or fine steel wire cut shot blasting; ⑨Non-destructive testing Carry out magnetic particle inspection on the workpiece, repair the surface micro cracks not exceeding 0.2mm in depth, and remove and scrap the workpiece with deep cracks; ⑩Cold plastic surgery; The workpiece is cold-formed so that the dimensional angle tolerance of the workpiece does not exceed ±0.5° and the length tolerance does not exceed ±0.76 mm; ⑪Surface treatment; The surface of the workpiece is treated to prevent rust.

[0017] Compared with the prior art, the present invention has the following outstanding beneficial effects: 1. The present invention can form multiple curved appearances in one bending process through a bending die, and the forming size reliability is high; 2. The present invention can make the long bar material blanking pattern connected front and back through the blanking die, resulting in less waste and high material utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the blanking die of the present invention; Figure 2yes Figure 1 A partial enlarged view of part A; Figure 3 It is a structural schematic diagram of the pressing mold of the present invention; Figure 4 It is a structural schematic diagram of the bending die of the present invention; Among them, 1. blanking upper template; 11. material pressing block; 12. cutter; 13. blanking upper bottom plate; 2. blanking lower template; 21. blanking lower bottom plate; 22. material receiving block; 23. positioning mechanism; 231. floating positioning block; 232. guide pin; 233. initial positioning surface; 234. subsequent positioning surface; 3. pressing upper template; 31. pressing upper bottom plate; 32. upper die stretching punch; 33. upper die pressing block; 34. corrugated upper die Block; 4, pressing lower template; 41, pressing lower bottom plate; 42, lower die concave block; 43, lower die positioning block; 44, corrugated lower template; 45, lower die positioning block; 5, bending upper template; 51, bending upper die bottom plate; 52, bending upper module; 53, upper die floating pre-pressing block; 6, bending lower template; 61, bending lower module; 62, lower die floating pre-pressing block; 63, bending lower die bottom plate; 64, roller; 65, bending lower positioning block. DETAILED DESCRIPTION

[0019] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0020] The invention comprises a blanking die, a pressing die and a bending die.

[0021] like Figure 1 As shown, the blanking die includes an upper blanking template 1 and a lower blanking template 2. The upper blanking template 1 includes an upper blanking base plate 13, a cutter 12 and a pressing block 11. The pressing block 11 is installed in the middle position of the lower end surface of the upper base plate, and the cutters 12 are respectively installed at both ends of the pressing block 11. The upper end of the cutter 12 is fixedly connected to the upper base plate.

[0022] In the optimization scheme, the upper bottom plate 13 of the blanking material is connected to the pressing block 11 through a pressing plate, and the upper bottom plate 13 of the blanking material and the pressing plate are connected by bolts. A spring is sleeved on the outside of the bolt, and the upper end of the spring is connected to the upper bottom plate 13 of the blanking material, and the lower end is connected to the pressing plate.

[0023] The blanking lower template 2 includes a blanking lower base plate 21, a receiving block 22 and a positioning mechanism 23. The upper end surface of the blanking lower base plate 21 is installed with a receiving block 22. The receiving block 22 is provided with a limiting cavity with a groove width of 22.1 mm±0.05mm and a depth of 2.5mm±0.05mm, which is used to position the blank in the width direction to prevent deflection; the positioning mechanism 23 is arranged at one end of the slot of the receiving block 22, and the positioning mechanism 23 includes a floating positioning block 231, a spring and a guide pin 232.

[0024] like Figure 2 As shown, a guide pin 232 is fixedly installed on the blanking lower base plate 21, a guide through hole is provided on the floating positioning block 231, the guide through hole of the floating positioning block 231 and the guide pin 232 slide up and down, a spring is sleeved on the outer side of the guide pin 232, the upper end of the spring is connected to the floating positioning block 231, and the lower end of the floating positioning block 231 is connected to the blanking lower base plate 21.

[0025] The floating positioning block 231 is in an inverted L-shape and is positioned in two levels. The upper level is an initial positioning surface 233 for initial punching and positioning of long blanks, and the lower level is a subsequent positioning surface 234 for subsequent blanking positioning.

[0026] like Figure 3 As shown, the pressing mold includes a pressing upper template 3 and a pressing lower template 4. The pressing upper template 3 includes a pressing upper base plate 31, an upper die stretching punch 32 and a corrugated upper module 34. The upper die stretching punch 32 and the corrugated upper template are fixedly installed on the lower end surface of the pressing upper base plate 31. The corrugated upper template has a wavy cavity. The upper die stretching punch 32 maintains a certain drop from the mold surface of the corrugated upper module 34.

[0027] The upper die stretch punch 32 is made with reverse concave characters.

[0028] In the optimized solution, the upper die stretch punch 32 is step-shaped, and its boss is installed on the pressing upper base plate 31.

[0029] The lower end of the press-formed upper base plate 31 is connected to the upper die pressing block 33 by bolts, and a spring is sleeved on the outer side of the bolt. The upper end of the spring is fixedly connected to the press-formed upper base plate 31, and the lower end is fixedly connected to the upper die pressing block 33. A through hole is provided on the upper die pressing block 33, and the upper die stretching punch 32 passes through the through hole of the upper die pressing block 33.

[0030] The embossing lower template 4 includes a embossing lower base plate 41, a lower die recess 42 and a corrugated lower template 44. The lower die recess 42 has a stretching groove corresponding to the upper die stretching punch 32. The corrugated lower template 44 has a wave-shaped cavity, and the corrugated lower template 44 corresponds to the cavity of the corrugated upper template.

[0031] The stretching groove of the lower die concave block 42 has a width of 22.25 mm±0.05 mm and a depth of 2.5 mm±0.05 mm, and is used to position the long blank in the width direction to prevent deflection.

[0032] A lower die positioning block is installed at one end of the corrugated lower die block to limit the length direction of the small blank.

[0033] In the optimization scheme, the lower end of the pressed lower base plate 41 is connected to the lower mold block by bolts, and a spring is sleeved on the outer side of the bolt. The upper end of the spring is fixedly connected to the pressed lower base plate 41, and the lower end is fixedly connected to the lower mold block. A through hole is provided on the lower mold block, and the lower mold recess 42 and the corrugated lower mold plate 44 respectively pass through the through holes of the lower mold block.

[0034] like Figure 4 As shown, the bending mold includes a bending upper template 5 and a bending lower template 6. The bending upper template 5 includes a bending upper template base plate 51, a bending upper module 52 and an upper template floating pre-pressure block 53. The lower end surface of the bending upper template base plate 51 is fixedly connected to the bending upper module 52. The lower end surface of the bending upper module 52 is a bending surface. The rear end of the bending upper module 52 is provided with a guide cavity with an opening at the lower end. The upper template floating pre-pressure block 53 is placed in the guide cavity of the bending upper module 52. The lower end of the upper template floating pre-pressure block 53 is a wavy cavity. The wavy cavity of the upper template floating pre-pressure block 53 corresponds to the wavy cavity of the corrugated upper template.

[0035] In the optimization scheme, a bolt is fixedly installed on the top wall of the guide cavity of the bending upper module 52, and a threaded blind hole is provided at the upper end of the upper mold floating pre-load block 53. The bolt is threadedly matched with the threaded blind hole of the upper mold floating pre-load block 53. A spring is sleeved on the outer side of the bolt, and the upper end of the spring is fixedly connected to the bending upper module 52, and the lower end is fixedly connected to the upper mold floating pre-load block 53.

[0036] The bending lower template 6 includes a bending lower template base plate 63, a bending lower module 61 and a lower template floating pre-load block 62. The upper end surface of the bending lower template base plate 63 is fixedly connected to the bending lower module 61. The front end of the bending lower module 61 is provided with a guide cavity with an upper end opening. The lower template floating pre-load block 62 is placed in the guide cavity of the bending upper module 52. The upper end of the lower template floating pre-load block 62 is rotatably connected to the roller 64. The front end portion of the upper end surface of the bending lower module 61 is a bending surface, and the rear end portion is a wave-spinning cavity. The wave-spinning cavity of the bending lower module 61 corresponds to the wave-spinning cavity of the corrugated lower template 44.

[0037] The lower bending module 61 is provided with a limiting groove with a depth of about 3 mm and a width of about 0.5 mm larger than the blank in the length direction.

[0038] In the optimization scheme, bolts are fixedly installed on the bottom wall of the guide cavity of the bending lower module 61, and a blind hole is provided at the lower end of the lower die floating preload block 62. The bolts are inserted into the blind hole of the lower die floating preload block 62. A spring is sleeved on the outer side of the bolt. The lower end of the spring is fixedly connected to the bending lower module 61, and the lower end is fixedly connected to the lower die floating preload block 62.

[0039] A lower bending positioning block 65 is fixedly mounted on the rear end wall of the lower bending module 61 .

[0040] A process for preparing a brake shoe latch using the above-mentioned mold specifically comprises the following steps: 1. Material heating; The long bar is heated in sections, and goes through four sections in sequence: preheating, heating, equalizing temperature and keeping warm. The temperatures are: 0-250℃±10℃, 250℃±10℃-1200℃±15℃, 1200℃±5℃, 1200℃±5℃. The total heating time for each bar is 10s-12s, which keeps the material fully heated and reduces oxidation of the material.

[0041] 2. Phosphorus removal; Use a dephosphorization machine to remove more than 90% of the oxide scale on the surface of the long bar, which is beneficial to maintain the surface quality of subsequent processing; the dephosphorization time is 8s to 10s.

[0042] 3. Rolling; During rolling, the long bar is roughly rolled to a thickness of 6±0.25 mm and a width of 18 mm±0.5 mm, then finely rolled to a thickness of 5.2±0.15 mm and a width of 21.8 mm±0.1 mm, and finally shaped into a long billet with a thickness of 5±0.1 mm and a width of 22 mm±0.1 mm; the total rolling time is 610 s.

[0043] 4. Blanking; Cut a single long blank and chamfer the two ends of the long blank C8; put the long blank into the limiting cavity of the receiving block 22 and position it with the floating positioning block 231 at the front end; the stamping time is 1s to 2s; The long billet is placed in the limiting cavity of the receiving block 22 and positioned with the initial positioning surface 233 of the floating positioning block 231 at the front end to complete the initial positioning; the upper template 1 for blanking moves downward, the pressing block 11 presses the long billet, and the cutter 12 cuts off the first small billet from both ends of the receiving block 22; the upper template 1 for blanking moves upward, driving the pressing block 11 and the cutter 12 upward to take out the first small billet; the long billet with the small billet cut off is placed in the limiting cavity of the receiving block 22 and positioned with the subsequent positioning surface 234 of the floating positioning block 231 to complete the secondary positioning; the upper template 1 for blanking moves downward, the pressing block 11 presses the long billet, and the cutter 12 cuts off the second small billet from both ends of the receiving block 22; the upper template 1 for blanking moves upward, driving the pressing block 11 and the cutter 12 upward to take out the second small billet; subsequently, the materials are unloaded in sequence according to the positioning method of the second small billet until the unloading is completed.

[0044] 5. Pressing; Place the small blank between the stretching groove of the lower die concave block 42 and the lower die positioning block to complete the initial positioning; the embossing upper template 3 moves downward, and the upper die stretching punch 32 presses the long blank, and the upper die stretching punch 32 cooperates with the stretching groove of the lower die concave block 42 to stretch out the workpiece boss and extrude the convex mark; at the same time, the corrugated upper module 34 and the corrugated lower module extrude the corrugated pattern of the workpiece; the embossing upper template 3 moves upward to take out the embossed workpiece, and the stamping time beat is 2s to 3s.

[0045] 6. Bending; The small blank after forming is positioned according to the corrugated end and placed on the limiting groove of the bending lower module 61; the small blank is lifted horizontally by the roller 64 of the lower die floating pre-pressing block 62; the bending upper template 5 moves downward, and the upper die floating pre-pressing block 53 first pre-presses the corrugated surface of the small blank, and at the same time, the lower die floating pre-pressing block 62 starts to move downward; the bending upper template 5 continues to move downward, the bending upper module 52 and the bending lower module 61 contact and gradually compact the small blank, and at the same time drive the lower die floating pre-pressing block 62 to continue to move downward, and the small blank is pulled by the roller 64 of the lower die floating pre-pressing block 62 and bent and deformed downward until the bending upper module 52 and the bending lower module 61 are relatively closed, and finally the blank is formed, the bending upper template 5 moves upward, and the lower die floating pre-pressing block 62 removes the formed workpiece from the die; the stamping time is 2s to 3s; 7. After the forming process is completed, the temperature is automatically sorted. If it is greater than or equal to 860℃, it will enter the heating and insulation line; otherwise, it will enter the heating and insulation line and then enter the crawler quenching and tempering line after reaching the design temperature; the tempering temperature is 460℃±5℃, and the tempering time is 120±15 min; the hardness after heat treatment reaches HRC44~52; the metallographic structure is better than level 4.

[0046] 8. Shot blasting; Use deficient sand or fine wire cut shot (specification Ф0.6 ~ 0.8 mm) for shot blasting. The time is measured by referring to the loading amount. Set it to 8 min ~ 10 min for each shot of 0.5t.

[0047] 9. NDT Carry out magnetic particle inspection on the workpiece, repair the surface micro cracks not exceeding 0.2mm in depth, and remove and scrap the workpiece with deep cracks.

[0048] 10. Cold shaping; The workpiece is cold-formed so that the dimensional angle tolerance of the workpiece does not exceed ±0.5° and the length tolerance does not exceed ±0.76 mm.

[0049] 11. Surface treatment; The surface of the workpiece is treated to prevent rust.

[0050] It should be noted that the specific embodiments of the present invention have been described in detail. For those skilled in the art, various obvious changes to the present invention without departing from the spirit and scope of the present invention are within the protection scope of the present invention.

Claims

1. A brake shoe latch preparation mold, comprising a blanking mold, a pressing mold and a bending mold; characterized in that: The blanking die comprises an upper blanking die plate (1) and a lower blanking die plate (2), wherein the upper blanking die plate (1) comprises an upper blanking base plate (13), a cutter (12) and a pressure block (11), wherein a pressure block (11) is installed in the middle of the lower end surface of the upper base plate, and cutters (12) are installed at both ends of the pressure block (11), and the upper end of the cutter (12) is fixedly connected to the upper base plate; the lower blanking die plate (2) comprises a lower blanking base plate (21), a receiving block (22) and a positioning mechanism (23), wherein a receiving block (22) is installed on the upper end surface of the lower blanking base plate (21), and the receiving block (22) is provided with a limiting cavity; the pressing die comprises an upper pressing die plate (3) and a pressing lower template (4), the pressing upper template (3) comprising a pressing upper base plate (31), an upper die stretching punch (32) and a corrugated upper template (34), the upper die stretching punch (32) and the corrugated upper template being fixedly mounted on the lower end surface of the pressing upper base plate (31), the corrugated upper template having a cavity in the shape of a wave; the pressing lower template (4) comprising a pressing lower base plate (41), a lower die concave block (42) and a corrugated lower template (44), the lower die concave block (42) having a stretching groove corresponding to the upper die stretching punch (32), the corrugated lower template (44) having a cavity in the shape of a wave, and the corrugated lower template (44) corresponding to the cavity of the corrugated upper template; the bending die comprising a bending die An upper folding template (5) and a lower bending template (6), wherein the upper bending template (5) comprises an upper bending template bottom plate (51), an upper bending module (52) and an upper floating pre-pressing block (53), wherein the lower end surface of the upper bending template bottom plate (51) is fixedly connected to the upper bending module (52), the lower end surface of the upper bending module (52) is a bending surface, the rear end of the upper bending module (52) is provided with a guide cavity with an opening at the lower end, the upper floating pre-pressing block (53) is placed in the guide cavity of the upper bending module (52), the lower end of the upper floating pre-pressing block (53) is a wave-spinning-shaped cavity, and the wave-spinning-shaped cavity of the upper floating pre-pressing block (53) corresponds to the wave-spinning-shaped cavity of the corrugated upper template; The bending lower template (6) comprises a bending lower template base plate (63), a bending lower module (61) and a lower template floating pre-pressing block (62); the upper end surface of the bending lower template base plate (63) is fixedly connected to the bending lower module (61); the front end of the bending lower module (61) is provided with a guide cavity with an upper end opening; the lower template floating pre-pressing block (62) is placed in the guide cavity of the bending upper module (52); the upper end of the lower template floating pre-pressing block (62) is rotatably connected to a roller (64); the front end portion of the upper end surface of the bending lower module (61) is a bending surface, and the rear end portion is a corrugated cavity; the corrugated cavity of the bending lower module (61) corresponds to the corrugated cavity of the corrugated lower template (44).

2. A brake shoe pin preparation mold according to claim 1, characterized in that: The blanking upper bottom plate (13) is connected to the pressing block (11) via a pressing plate, and the blanking upper bottom plate (13) and the pressing plate are connected via bolts. A spring is sleeved on the outer side of the bolt, and the upper end of the spring is connected to the blanking upper bottom plate (13), and the lower end is connected to the pressing plate.

3. A brake shoe pin preparation mold according to claim 1, characterized in that: The positioning mechanism (23) is arranged at one end of the slot of the material receiving block (22), and the positioning mechanism (23) comprises a floating positioning block (231), a spring and a guide pin (232); the guide pin (232) is fixedly mounted on the blanking lower bottom plate (21), the floating positioning block (231) is provided with a guide through hole, the guide through hole of the floating positioning block (231) and the guide pin (232) are slidably matched up and down, the outer side of the guide pin (232) is sleeved with a spring, the upper end of the spring is connected to the floating positioning block (231), and the lower end of the floating positioning block (231) is connected to the blanking lower bottom plate (21).

4. A brake shoe pin preparation mold according to claim 1, characterized in that: The upper die stretching punch (32) is in a step shape, and its boss is mounted on the pressing upper base plate (31).

5. A brake shoe pin preparation mold according to claim 1, characterized in that: The lower end of the press-formed upper base plate (31) is connected to the upper die pressing block (33) by means of bolts. A spring is sleeved on the outer side of the bolts. The upper end of the spring is fixedly connected to the press-formed upper base plate (31), and the lower end of the spring is fixedly connected to the upper die pressing block (33). The upper die pressing block (33) is provided with a through hole, and the upper die stretching punch (32) passes through the through hole of the upper die pressing block (33).

6. A brake shoe pin preparation mold according to claim 1, characterized in that: A lower die positioning block is installed at one end of the corrugated lower die block.

7. A brake shoe pin preparation mold according to claim 1, characterized in that: The lower end of the press-formed lower bottom plate (41) is connected to the lower die pressing block via a bolt, a spring is sleeved on the outer side of the bolt, the upper end of the spring is fixedly connected to the press-formed lower bottom plate (41), and the lower end of the spring is fixedly connected to the lower die pressing block, a through hole is provided on the lower die pressing block, and the lower die concave block (42) and the corrugated lower mold plate (44) respectively pass through the through holes of the lower die pressing block.

8. A process for preparing a brake shoe latch based on the above mold, characterized in that: The following steps are included: ① Material heating; The long bar is heated in sections, and goes through four stages: preheating, heating, equalizing temperature, and keeping warm. ② Phosphorus removal treatment; Use a dephosphorization machine to remove the oxide scale on the surface of the long bar, which is beneficial to maintain the surface quality of subsequent processing; ③ Rolling billets; During rolling, the long bar is roughly rolled to a thickness of 6±0.25 mm and a width of 18 mm±0.5 mm, then finely rolled to a thickness of 5.2±0.15 mm and a width of 21.8 mm±0.1 mm, and finally shaped to a long billet of 5±0.1 mm in thickness and 22 mm±0.1 mm in width; ④Blanking; A single long blank is cut and both ends of the long blank are chamfered to C8; the long blank is placed in the limiting cavity of the receiving block (22) and positioned by the floating positioning block (231) at the front end; the long blank is placed in the limiting cavity of the receiving block (22) and positioned by the initial positioning surface (233) of the floating positioning block (231) at the front end to complete the initial positioning; the blanking upper template (1) moves downward, the pressing block (11) presses the long blank, and the cutter (12) cuts the first small blank from both ends of the receiving block (22); the blanking upper template (1) moves upward, driving the pressing block (11) and the cutter ( 12) moves upward to take out the first small blank; the long blank cut from the small blank is placed in the limiting cavity of the receiving block (22) and positioned on the subsequent positioning surface (234) of the floating positioning block (231) to complete the secondary positioning; the blanking upper template (1) moves downward, the pressing block (11) presses the long blank, and the cutter (12) cuts off the second small blank from both ends of the receiving block (22); the blanking upper template (1) moves upward, driving the pressing block (11) and the cutter (12) to move upward to take out the second small blank; and subsequently, blanking is performed in sequence according to the positioning method of the second small blank until blanking is completed; ⑤ Pressing; The small blank is placed between the stretching groove of the lower die concave block (42) and the lower die positioning block to complete the initial positioning; the upper die pressing plate (3) moves downward, the upper die stretching punch (32) presses the long blank, and the upper die stretching punch (32) cooperates with the stretching groove of the lower die concave block (42) to stretch out the workpiece boss and extrude the convex character mark; at the same time, the corrugated upper die block (34) and the corrugated lower die block extrude the corrugated pattern of the workpiece; the upper die pressing plate (3) moves upward to take out the workpiece after pressing; ⑥Bending; The small blank after being pressed is positioned according to the corrugated end and placed on the limiting groove of the bending lower module (61); the small blank is lifted horizontally by the roller (64) of the lower die floating pre-pressing block (62); the bending upper template (5) moves downward, the upper die floating pre-pressing block (53) first pre-presses the corrugated surface of the small blank, and at the same time the lower die floating pre-pressing block (62) starts to move downward; the bending upper template (5) continues to move downward, the bending upper module (52) and the bending lower module (61) contact and gradually compact the small blank, and at the same time drive the lower die floating pre-pressing block (62) to continue to move downward, the small blank is pulled by the roller (64) of the lower die floating pre-pressing block (62) and bent and deformed downward, until the bending upper module (52) and the bending lower module (61) are relatively closed, and finally the blank is formed, the bending upper template (5) moves upward, and the lower die floating pre-pressing block (62) removes the formed workpiece from the mold; ⑦ After the forming process is completed, the temperature is automatically sorted, and if it is greater than or equal to 860℃, it will enter the heating and insulation line; Otherwise, it will enter the heating and holding line and then enter the crawler quenching and tempering line after reaching the design temperature; the tempering temperature is 460℃±5℃, the tempering time is 120±15 min; the hardness after heat treatment reaches HRC44~52; the metallographic structure is better than grade 4; ⑧ Shot blasting; Choose sand-less or fine steel wire cut shot blasting; ⑨Non-destructive testing Carry out magnetic particle inspection on the workpiece, repair the surface micro cracks not exceeding 0.2mm in depth, and remove and scrap the workpiece with deep cracks; ⑩Cold plastic surgery; Cold shaping is performed on the workpiece so that the dimensional angle tolerance of the workpiece does not exceed ±0.5° and the length tolerance does not exceed ±0.76mm; ⑪Surface treatment; The surface of the workpiece is treated to prevent rust.

Images