A method for forming a copper-chromium alloy eccentric part by using a combined half die

Abstract

The application discloses a forming method of copper-chromium alloy eccentric parts by adopting a combined Haver die body extrusion, and comprises the following steps: S1, blanking: cutting a bar, the volume of the bar being 105-110% of the volume of the eccentric part, so as to obtain a copper-chromium alloy blank; S2, heating the copper-chromium alloy blank: heating the copper-chromium alloy blank to 940-960 DEG C and keeping the temperature for 8-15 min; S3, first stamping: placing the copper-chromium alloy blank into a lower die of a Haver die body, and stamping out the shape of the part by using an upper die of the Haver die body; and S4, second stamping: stamping out the wiring hole of the eccentric part by using the upper die of the Haver die body; the process forming mode is efficient, and solves the problems of high scrap product rate, low material utilization rate, forming difficulty, and too large working load in the forging process of traditional conventional eccentric copper-chromium alloy forging; the method reduces cracks, wrinkles, pores, slag inclusion and other defects in the forged parts caused by the characteristics of the copper-chromium alloy material, and improves the qualified rate of part production.

Description

Technical Field

[0001] This invention relates to the field of metal blank forming technology, specifically to a method for forming eccentric copper-chromium alloy parts by extruding using a combined Haver die. Background Technology

[0002] Eccentric copper-chromium alloy parts are commonly used in high-voltage vacuum circuit breakers and are important current-carrying components. Due to the characteristics of vacuum circuit breakers, the material of these parts must be free of various defects.

[0003] Traditional eccentric blank forming of copper-chromium alloys typically employs forging. Due to the characteristics of copper-chromium alloys, forging easily causes a series of defects such as internal cracks, wrinkles, porosity, and inclusions, resulting in a low product qualification rate. Furthermore, copper-chromium alloys are expensive, forging processes require large blank allowances, and the forging process involves excessively high operator frequency and labor intensity, all of which severely impact the processing efficiency and cost of parts. Summary of the Invention

[0004] The purpose of this invention is to provide a method for forming copper-chromium alloy eccentric parts by extruding using a combined Haval mold, which enables efficient stamping production of copper-chromium alloy eccentric parts used in high-voltage vacuum circuit breakers.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A method for forming eccentric copper-chromium alloy parts by extruding using a combined Haval mold includes the following steps: S1. Material feeding: Cut the bar stock, the volume of which is 105-110% of the volume of the eccentric part; S2. Heating copper-chromium alloy billet: Heat the copper-chromium alloy billet to 940~960℃ and hold for 8~15 minutes; S3, First stamping: The copper-chromium alloy blank is placed into the lower mold of the Haval mold body. A 100t stamping press is used, and the stamping time is 1 second. The shape of the part is first stamped out using one of the upper molds of the Haval mold body. One of the upper molds of the Haval mold body has the same inner hole size as the lower mold of the Haval mold body; S4, Second stamping: A 100t stamping press is used, with a stamping time of 1 second. Then, the wiring hole of the eccentric part is stamped out using the upper die of the Haval mold body. One end of the eccentric part has a wiring hole, and the outer dimensions of the second mold of the Haval mold body are consistent with the dimensions of the wiring hole; S5. Part demolding: The lower mold of the Haval mold body is ejected from the mold fixing sleeve by using the ejector pin, and the stamped copper-chromium alloy eccentric part is demolded and taken out from the lower mold of the Haval mold body; S6. Part Shaping: The copper-chromium alloy eccentric parts are shaped, the stamping burrs are removed by grinding, and then polished to make the surface smooth and clean, so that the surface roughness of the parts reaches Ra0.1~Ra0.2, and the finished copper-chromium alloy eccentric parts are obtained.

[0006] Preferably, in step S3, the interior of the lower mold of the Haval mold body is preheated first, and then the copper-chromium alloy billet is placed into the lower mold of the Haval mold body. The preheating temperature is 650~700℃.

[0007] Preferably, in step S3, after the wiring hole of the eccentric part is punched out by the second die of the upper die of the Haval mold body, the part is then re-punched using a high-speed impact frequency of 1500Hz~2500 Hz, the punching force is 25%~35% of that of the first punching, and the high-frequency punching lasts for 5~10 seconds.

[0008] Preferably, in step S4, after the wiring hole of the eccentric part is punched out by the upper die of the Haval mold body, the part is then re-punched using a high-speed impact frequency of 1000Hz~1500Hz, the punching force is 25%~35% of that of the second punching, and the high-frequency punching lasts for 8~15s.

[0009] Preferably, in step S6, the polishing is performed using laser cleaning polishing, with the laser having a wavelength of 532 nm and an energy density of 1~10 J / cm². 2 The light source.

[0010] Preferably, as described above, the method for forming eccentric copper-chromium alloy parts by extruding a combined Haval mold includes a lower Haval mold, and one upper Haval mold and another upper Haval mold used in conjunction with the lower Haval mold. The lower mold of the Haval mold body has a cavity forming hole, and the lower mold of the Haval mold body is composed of two parts spliced ​​together along the axial plane of the cavity forming hole; The upper mold of the Haval mold body includes an upper mold connecting seat and an upper mold end face stamping column connected to the lower end of the upper mold connecting seat. The second upper mold of the Haval mold body includes a second upper mold connecting seat and a second upper mold inner hole stamping column connected to the lower end of the second upper mold connecting seat.

[0011] Preferably, the lower die of the Haval mold body is connected to the table of the stamping machine through a lower die fixing mechanism. The lower die fixing mechanism includes a lower die fixing plate, and a die positioning plate is fixed on the top of the lower die fixing plate. The top of the die positioning plate has a positioning and receiving groove. The top of the die positioning plate is fixed with a lower die outer fixing sleeve, and the lower die outer fixing sleeve is fixed with a die fixing constraint sleeve inside the die fixing sleeve. The lower mold of the Haval mold body is fixed and constrained in the die fixing and constraining sleeve, and the die forming hole opening is arranged facing upward; The lower mold fixing plate has multiple vertical through screw connection holes, the lower end of the lower mold outer fixing sleeve has multiple screw fixing holes, and the cavity positioning plate has multiple through screw holes for connecting the screw connection holes and the screw fixing holes. Fastening screws are connected in the screw connection holes and are threaded through the screw through holes and fixed in the screw fixing holes. The cavity positioning plate has a vertically penetrating ejector pin receiving hole, and the lower mold fixing plate has an ejector pin mating through hole that is coaxial with the ejector pin receiving hole. A demolding ejector pin is slidably connected inside the ejector pin receiving hole.

[0012] Note: The lower die fixing mechanism provides good and stable support for the lower die of the Haval mold body, preventing the mold from shifting or misaligning during the stamping process. It also facilitates quick assembly and disassembly of the lower die of the Haval mold body, making it easy to demold and remove the stamped parts.

[0013] Preferably, the inner side of the lower mold outer fixing sleeve has a tapered shape that is wider at the bottom and narrower at the top, with the tapered shape ranging from (1:10) to (1:5). The outer side of the die fixing sleeve has a taper that is the same size as the inner side of the lower die outer fixing sleeve; The inner side of the die fixing constraint sleeve has a taper that is narrower at the bottom and wider at the top, with the taper range being (1:15) to (1:10). The outer side of the lower mold of the Haval mold body has a taper that is the same size as the inner side of the die fixing constraint sleeve.

[0014] Note: This structural design not only provides good stability for the lower mold of the Haval mold body, preventing unnecessary gap shaking during operation, but also facilitates quick assembly and disassembly of the lower mold of the Haval mold body.

[0015] Preferably, both the first upper die of the Haval mold body and the second upper die of the Haval mold body are connected to the slide block of the stamping machine through an upper die fixing mechanism. The upper die fixing mechanism includes an upper die fixing plate, an upper die fixing block is fixed at the lower end of the upper die fixing plate, and the upper die fixing block has a vertically penetrating upper die fixing constraint hole. The connecting seat of the first upper die is fixedly constrained in the upper die fixing constraint hole.

[0016] Preferably, the upper mold fixing mechanism has an upper mold quick-change mechanism, which includes a quick-change mechanism fixing plate fixed to the lower end of the upper mold fixing plate. The lower end of the quick-change mechanism fixing plate has a plurality of quick-change constraint slide grooves extending radially therein. A quick-change synchronous slider is slidably connected in the quick-change constraint slide groove. A sliding connecting column is fixed to the lower end of the quick-change synchronous slider. The lower end of the quick-change mechanism fixed plate is rotatably connected to a sliding drive plate. The sliding drive plate has multiple vertically penetrating sliding drive constraint grooves. The sliding drive constraint grooves extend spirally along the surface of the sliding drive plate, dividing the upper mold fixed block into multiple upper mold fixed partition blocks along its radial plane. The sliding connecting column passes through the sliding drive constraint grooves and is fixedly connected to the upper mold fixed partition blocks one by one. The quick-change mechanism has a drive disc synchronous ring rotatably connected to the outside of the fixed disc. The drive disc synchronous ring is fixedly connected to the sliding drive disc, and a drive handle is fixed to the outside of the drive disc synchronous ring.

[0017] Note: The quick-change upper mold mechanism allows workers to easily disassemble and replace the first upper mold and the second upper mold of the Haval mold body, improving work efficiency.

[0018] Compared with the prior art, the beneficial effects of the present invention are reflected in the following aspects: 1. The process for producing copper-chromium alloy eccentric parts in this invention is highly efficient in forming and solves the problems of high scrap rate, low material utilization, difficult forming, and excessive workload in the traditional conventional eccentric copper-chromium alloy forging process. 2. The process for producing copper-chromium alloy eccentric parts according to the present invention significantly reduces a series of defects such as cracks, wrinkles, porosity, and slag inclusions inside forged parts caused by the characteristics of copper-chromium alloy materials, and greatly improves the pass rate of parts production. 3. The process for producing copper-chromium alloy eccentric parts according to the present invention has a relatively small blank allowance, which saves a lot of raw materials, and the forging process only requires a small number of personnel to operate. Attached Figure Description

[0019] Figure 1 This is the front view of the present invention; Figure 2 This is a schematic diagram of the structure of the second upper mold of the Haval mold body of the present invention; Figure 3 This is a bottom view of the quick-change mechanism for the upper mold of the present invention.

[0020] In the diagram, 10-Haval mold lower die, 11-Die forming hole, 20-Haval mold upper die one, 21-Upper die one connecting seat, 22-Upper die one end face stamping column, 30-Haval mold upper die two, 31-Upper die two connecting seat, 32-Upper die two inner hole stamping column, 40-Lower die fixing mechanism, 41-Lower die fixing plate, 411-Screw connecting hole, 42-Die positioning plate, 420-Positioning receiving groove, 421-Screw through hole, 43-Lower die outer fixing sleeve, 431-Screw fixing hole, 44-Die die fixing constraint sleeve. 45-Fasting screw, 46-Ejector pin, 461-Ejector pin receiving hole, 462-Ejector pin mating through hole, 50-Upper mold fixing mechanism, 51-Upper mold fixing plate, 52-Upper mold fixing block, 520-Upper mold fixing partition block, 521-Upper mold fixing constraint hole, 53-Upper mold quick change mechanism, 531-Quick change mechanism fixing plate, 532-Quick change constraint slide, 533-Quick change synchronous slider, 534-Sliding connecting column, 535-Sliding drive plate, 536-Sliding drive constraint groove, 537-Drive plate synchronous ring, 538-Drive handle. Detailed Implementation

[0021] The following is combined Figures 1-3 The present invention will be described in detail. For ease of description, the orientations mentioned below are defined as follows: The directions of up, down, left, right, front, and back mentioned below are consistent with the directions of up, down, left, right, front, and back in the projection relationship of the respective main view or structural schematic diagram.

[0022] Example 1: A method for forming eccentric copper-chromium alloy parts by extruding using a combined Haval mold includes the following steps: S1. Material feeding: Cut the bar stock; the volume of the bar stock is 110% of the volume of the eccentric part. S2. Heating copper-chromium alloy billet: The copper-chromium alloy billet is heated to 960℃ and held at that temperature for 15 minutes. S3, First stamping: First, preheat the inside of the lower mold of the Haval mold body, and then put the copper-chromium alloy billet into the lower mold of the Haval mold body. The preheating temperature is 700℃. The copper-chromium alloy blank is placed into the lower mold of the Haval mold body. A 100t stamping press is used, and the stamping time is 1 second. The shape of the part is first stamped out using one of the upper molds of the Haval mold body. Next, the parts are re-stamped using a high-speed impact frequency of 2500 Hz, with a stamping force of 35% of that of the first stamping, and high-frequency stamping for 10 seconds. One of the upper molds of the Haval mold body has the same inner hole size as the lower mold of the Haval mold body; S4, Second stamping: A 100t stamping press is used, with a stamping time of 1 second. Then, the wiring hole of the eccentric part is stamped out using the upper die of the Haval mold body. Next, the parts are re-stamped using a high-speed impact frequency of 1500 Hz, with the stamping force being 35% of that used in the second stamping, and the high-frequency stamping lasting for 15 seconds. One end of the eccentric part has a wiring hole, and the outer dimensions of the second mold of the Haval mold body are consistent with the dimensions of the wiring hole; S5. Part demolding: The lower mold of the Haval mold body is ejected from the mold fixing sleeve by using the ejector pin, and the stamped copper-chromium alloy eccentric part is demolded and taken out from the lower mold of the Haval mold body; S6. Part Shaping: The copper-chromium alloy eccentric parts are shaped, the stamping burrs are removed by grinding, and then laser treatment is performed with a wavelength of 532nm and an energy density of 10J / cm². 2 The light source polishes the surface to make it smooth and clean, so that the surface roughness of the part reaches Ra0.2, and the finished copper-chromium alloy eccentric part can be obtained.

[0023] Example 2: A method for forming eccentric copper-chromium alloy parts by extruding using a combined Haval mold includes the following steps: S1. Material feeding: Cut the bar stock; the volume of the bar stock is 105% of the volume of the eccentric part. S2. Heating copper-chromium alloy billet: The copper-chromium alloy billet is heated to 940℃ and held at that temperature for 8 minutes. S3, First stamping: First, preheat the inside of the lower mold of the Haval mold body, and then put the copper-chromium alloy billet into the lower mold of the Haval mold body. The preheating temperature is 650℃. The copper-chromium alloy blank is placed into the lower mold of the Haval mold body. A 100t stamping press is used, and the stamping time is 1 second. The shape of the part is first stamped out using one of the upper molds of the Haval mold body. Next, the parts are re-stamped using a high-speed impact frequency of 1500Hz, with a stamping force of 25% of that of the first stamping, for 5 seconds. One of the upper molds of the Haval mold body has the same inner hole size as the lower mold of the Haval mold body; S4, Second stamping: A 100t stamping press is used, with a stamping time of 1 second. Then, the wiring hole of the eccentric part is stamped out using the upper die of the Haval mold body. Next, the parts are re-stamped using a high-speed impact frequency of 1000Hz, with a stamping force of 25% of that used in the second stamping, for 8 seconds. One end of the eccentric part has a wiring hole, and the outer dimensions of the second mold of the Haval mold body are consistent with the dimensions of the wiring hole; S5. Part demolding: The lower mold of the Haval mold body is ejected from the mold fixing sleeve by using the ejector pin, and the stamped copper-chromium alloy eccentric part is demolded and taken out from the lower mold of the Haval mold body; S6. Part Shaping: The copper-chromium alloy eccentric parts are shaped, the stamping burrs are removed by grinding, and then laser treatment is performed with a wavelength of 532nm and an energy density of 1J / cm². 2 The light source polishes the surface to make it smooth and clean, so that the surface roughness of the part reaches Ra0.1, and the finished copper-chromium alloy eccentric part can be obtained.

[0024] Example 3: A method for forming eccentric copper-chromium alloy parts by extruding using a combined Haval mold includes the following steps: S1. Material feeding: Cut the bar stock; the volume of the bar stock is 106% of the volume of the eccentric part. S2. Heating copper-chromium alloy billet: The copper-chromium alloy billet is heated to 950℃ and held for 12 minutes; S3, First stamping: First, preheat the inside of the lower mold of the Haval mold body, and then put the copper-chromium alloy billet into the lower mold of the Haval mold body. The preheating temperature is 680℃. The copper-chromium alloy blank is placed into the lower mold of the Haval mold body. A 100t stamping press is used, and the stamping time is 1 second. The shape of the part is first stamped out using one of the upper molds of the Haval mold body. Next, the parts are re-stamped using a high-speed impact frequency of 1800Hz, with the stamping force being 30% of that used in the first stamping, for 8 seconds. One of the upper molds of the Haval mold body has the same inner hole size as the lower mold of the Haval mold body; S4, Second stamping: A 100t stamping press is used, with a stamping time of 1 second. Then, the wiring hole of the eccentric part is stamped out using the upper die of the Haval mold body. Next, the parts are re-stamped using a high-speed impact frequency of 1350Hz, with the stamping force being 30% of that used in the second stamping, and the high-frequency stamping lasting for 10 seconds. One end of the eccentric part has a wiring hole, and the outer dimensions of the second mold of the Haval mold body are consistent with the dimensions of the wiring hole; S5. Part demolding: The lower mold of the Haval mold body is ejected from the mold fixing sleeve by using the ejector pin, and the stamped copper-chromium alloy eccentric part is demolded and taken out from the lower mold of the Haval mold body; S6. Part Shaping: The copper-chromium alloy eccentric parts are shaped, the stamping burrs are removed by grinding, and then laser treatment is performed with a wavelength of 532nm and an energy density of 6J / cm². 2 The light source polishes the surface to make it smooth and clean, so that the surface roughness of the part reaches Ra0.1, and the finished copper-chromium alloy eccentric part can be obtained.

[0025] Example 4: This embodiment describes the structure of a combined Haval mold used in the above embodiment 3 for forming copper-chromium alloy eccentric parts by extruding a combined Haval mold. The combined Haval mold includes a lower Haval mold 10, and a first Haval mold 20 and a second Haval mold 30 used in conjunction with the lower Haval mold 10. The lower mold 10 of the Haval mold body has a cavity forming hole 11. The lower mold 10 of the Haval mold body is composed of two parts spliced ​​together along the axial plane of the cavity forming hole 11. The upper mold 20 of the Haval mold body includes an upper mold connecting seat 21 and an upper mold end face stamping column 22 connected to the lower end of the upper mold connecting seat 21. The second upper mold 30 of the Haval mold body includes a second upper mold connecting seat 31 and a second upper mold inner hole stamping column 32 connected to the lower end of the second upper mold connecting seat 31.

[0026] The lower mold 10 of the Haval mold body is connected to the table of the stamping machine through the lower mold fixing mechanism 40. The lower mold fixing mechanism 40 includes a lower mold fixing plate 41, and a die positioning plate 42 is fixed on the top of the lower mold fixing plate 41. The die positioning plate 42 has a positioning and receiving groove 420 on the top. The top of the die positioning plate 42 is fixed with a lower die outer fixing sleeve 43, and the lower die outer fixing sleeve 43 is fixed with a die fixing constraint sleeve 44 inside the die fixing sleeve 43. The lower mold 10 of the Haval mold body is fixedly constrained in the die fixing constraint sleeve 44, and the die forming hole 11 is arranged with the opening facing upward. The lower mold fixing plate 41 has multiple vertically penetrating screw connection holes 411, the lower end of the lower mold outer fixing sleeve 43 has multiple screw fixing holes 431, the cavity mold positioning plate 42 has multiple screw through holes 421 for connecting the screw connection holes 411 and the screw fixing holes 431, a fastening screw 45 is connected in the screw connection hole 411, and the fastening screw 45 passes through the screw through hole 421 and is threaded in the screw fixing hole 431; The cavity positioning plate 42 has a vertically penetrating ejector pin receiving hole 461, and the lower mold fixing plate 41 has an ejector pin mating through hole 462 that is coaxially connected to the ejector pin receiving hole 461. A demolding ejector pin 46 is slidably connected inside the ejector pin receiving hole 461.

[0027] The inner side of the lower mold outer fixing sleeve 43 has a tapered shape that is wider at the bottom and narrower at the top, with a tapered ratio of 1:5; The outer side of the die fixing sleeve 44 has a taper that is the same size as the inner side of the lower die outer fixing sleeve 43; The inner side of the die fixing constraint sleeve 44 has a taper that is narrower at the bottom and wider at the top, with a taper ratio of 1:10; The outer side of the lower mold 10 of the Haval mold body has a taper that is the same size as the inner side of the die fixing constraint sleeve 44.

[0028] Both the first upper die 20 and the second upper die 30 of the Haval mold body are connected to the slide block of the stamping machine through the upper die fixing mechanism 50. The upper die fixing mechanism 50 includes an upper die fixing plate 51, and an upper die fixing block 52 is fixed at the lower end of the upper die fixing plate 51. The upper die fixing block 52 has a vertically penetrating upper die fixing constraint hole 521, and the first upper die connecting seat 21 is fixedly constrained in the upper die fixing constraint hole 521.

[0029] The upper mold fixing mechanism 50 has an upper mold quick change mechanism 53. The upper mold quick change mechanism 53 includes a quick change mechanism fixing plate 531 fixed to the lower end of the upper mold fixing plate 51. The lower end of the quick change mechanism fixing plate 531 has a plurality of quick change constraint slide grooves 532 extending radially therein. A quick change synchronous slider 533 is slidably connected in the quick change constraint slide groove 532. A sliding connecting column 534 is fixed to the lower end of the quick change synchronous slider 533. The lower end of the quick-change mechanism fixed plate 531 is rotatably connected to the sliding drive plate 535. The sliding drive plate 535 has multiple vertically penetrating sliding drive constraint grooves 536. The sliding drive constraint grooves 536 extend spirally along the plate surface of the sliding drive plate 535, dividing the upper mold fixed block 52 into multiple upper mold fixed partition blocks 520 along its radial plane. The sliding connecting column 534 passes through the sliding drive constraint grooves 536 and is fixedly connected to the upper mold fixed partition blocks 520 one by one. A drive disk synchronization ring 537 is rotatably connected to the outer side of the quick-change mechanism fixed plate 531. The drive disk synchronization ring 537 is fixedly connected to the sliding drive plate 535. A drive handle 538 is fixed to the outer side of the drive disk synchronization ring 537.

[0030] Example 5: The difference from Embodiment 4 is that the inner side of the lower mold outer fixing sleeve 43 has a tapered shape that is wider at the bottom and narrower at the top, with a tapered ratio of 1:10; The inner side of the die fixing constraint sleeve 44 has a taper that is narrower at the bottom and wider at the top, with a taper ratio of 1:15.

[0031] Example 6: The difference from Example 4 is that the inner side of the lower mold outer fixing sleeve 43 has a tapered shape that is wider at the bottom and narrower at the top, with a tapered ratio of 1:8; The inner side of the die fixing constraint sleeve 44 has a taper that is narrower at the bottom and wider at the top, with a taper ratio of 1:12.

[0032] In practical applications, the copper-chromium alloy eccentric part of this invention has the following structure: one end of a column is connected to an end column that is eccentric to it, and the other end of the column has a connection hole. The copper-chromium alloy eccentric part is used to connect the contacts in a high-voltage vacuum circuit breaker. The lower die fixing plate 41 is fixedly connected to the platform of the stamping machine by multiple fastening bolts, and the upper die fixing plate 51 is fixedly connected to the slide of the stamping machine. When switching between the first upper mold 20 and the second upper mold 30 of the Haval mold body, simply turn the drive handle 538. The drive handle 538 drives the synchronous ring 537 of the drive disk and the sliding drive disk 535 to rotate together. Under the constraint of the sliding drive constraint groove 536, the sliding drive constraint groove 536 drives the sliding connecting column 534 and the quick-change synchronous slider 533 to move along the quick-change constraint groove 532. Each sliding connecting column 534 then drives the upper mold fixing partition block 520 to move away from each other synchronously, so that the first upper mold connecting seat 21 of the first upper mold 20 of the Haval mold body is disengaged from the upper mold fixing constraint hole 521. Then, the second upper mold connecting seat 31 of the second upper mold 30 of the Haval mold body is placed into the upper mold fixing constraint hole 521. Turn the drive handle 538 in the opposite direction to make each upper mold fixing partition block 520 move closer to each other synchronously, and fix the second upper mold connecting seat 31 in the upper mold fixing constraint hole 521.

Claims

1. A method for forming eccentric copper-chromium alloy parts by extruding using a combined Haval mold, characterized in that, Includes the following steps: S1. Material feeding: Cut the bar stock, the volume of which is 105~110% of the volume of the eccentric part, to obtain a copper-chromium alloy billet. S2. Heating copper-chromium alloy billet: Heat the copper-chromium alloy billet to 940~960℃ and hold for 8~15 minutes; S3, First stamping: The copper-chromium alloy blank is placed into the lower mold of the Haval mold body. A 100t stamping press is used, and the stamping time is 1 second. The shape of the part is first stamped out using one of the upper molds of the Haval mold body. One of the upper molds of the Haval mold body has the same inner hole size as the lower mold of the Haval mold body; In step S3, the interior of the lower mold of the Haval mold body is preheated first, and then the copper-chromium alloy billet is placed into the lower mold of the Haval mold body. The preheating temperature is 650~700℃. In step S3, the part is first stamped out using one of the upper dies of the Haval mold body, and then the part is re-stamped using a high-speed impact frequency of 1500Hz~2500 Hz, with the stamping force being 25%~35% of that of the first stamping, and the high-frequency stamping lasting 5~10 seconds. S4, Second stamping: A 100t stamping press is used, with a stamping time of 1 second. Then, the wiring hole of the eccentric part is stamped out using the upper die of the Haval mold body. One end of the eccentric part has a wiring hole, and the outer dimensions of the second mold of the Haval mold body are consistent with the dimensions of the wiring hole; In step S4, after the wiring hole of the eccentric part is punched out by the upper die of the Haval mold body, the part is then re-punched using a high-speed impact frequency of 1000Hz~1500 Hz, the punching force is 25%~35% of that of the second punching, and the high-frequency punching lasts for 8~15s. S5. Part demolding: The lower mold of the Haval mold body is ejected from the mold fixing sleeve by using the ejector pin, and the stamped copper-chromium alloy eccentric part is demolded and taken out from the lower mold of the Haval mold body; S6. Part Shaping: The copper-chromium alloy eccentric parts are shaped, the stamping burrs are removed by grinding, and then polished to make the surface smooth and clean, so that the surface roughness of the parts reaches Ra0.1~Ra0.2, and the finished copper-chromium alloy eccentric parts are obtained.

2. The method for forming eccentric copper-chromium alloy parts by extrusion using a combined Haval die as described in claim 1, characterized in that: In step S6, polishing is performed using laser cleaning and polishing. The laser has a wavelength of 532nm and an energy density of 1~10J / cm². 2 The light source.

3. A method for forming eccentric copper-chromium alloy parts by extruding using a combined Haval die, as described in any one of claims 1 to 2, characterized in that... The combined Haval mold includes a lower Haval mold (10), and a first Haval mold (20) and a second Haval mold (30) used in conjunction with the lower Haval mold (10). The lower mold (10) of the Haval mold body has a concave mold forming hole (11), and the lower mold (10) of the Haval mold body is divided into two parts and spliced ​​together along the axial plane of the concave mold forming hole (11); The upper mold of the Haval mold (20) includes an upper mold connecting seat (21) and an upper mold end face stamping column (22) connected to the lower end of the upper mold connecting seat (21). The second upper mold (30) of the Haval mold body includes a second upper mold connecting seat (31) and a second upper mold inner hole stamping column (32) connected to the lower end of the second upper mold connecting seat (31).

4. The method for forming eccentric copper-chromium alloy parts by extrusion using a combined Haval die as described in claim 3, characterized in that: The lower mold (10) of the Haval mold body is connected to the platform of the stamping machine through the lower mold fixing mechanism (40). The lower mold fixing mechanism (40) includes a lower mold fixing plate (41). A die positioning plate (42) is fixed on the top of the lower mold fixing plate (41). The die positioning plate (42) has a positioning and receiving groove (420) on the top. The top of the die positioning plate (42) is fixed with a lower die outer fixing sleeve (43), and the lower die outer fixing sleeve (43) is fixed with a die fixing constraint sleeve (44). The lower mold (10) of the Haval mold body is fixedly constrained in the die fixing constraint sleeve (44), and the die forming hole (11) is arranged with the opening facing upward; The lower mold fixing plate (41) has multiple vertically penetrating screw connection holes (411), the lower mold outer fixing sleeve (43) has multiple screw fixing holes (431) at its lower end, the concave mold positioning plate (42) has multiple screw through holes (421) for connecting the screw connection holes (411) and the screw fixing holes (431), a fastening screw (45) is connected in the screw connection hole (411), and the fastening screw (45) passes through the screw through hole (421) and is threaded in the screw fixing hole (431); The cavity positioning plate (42) has a vertically penetrating ejector rod receiving hole (461), and the lower mold fixing plate (41) has an ejector rod mating through hole (462) coaxially penetrating the ejector rod receiving hole (461). A demolding ejector rod (46) is slidably connected in the ejector rod receiving hole (461).

5. The method for forming eccentric copper-chromium alloy parts by extrusion using a combined Haval die as described in claim 4, characterized in that: The inner side of the lower mold outer fixing sleeve (43) has a tapered shape that is wider at the bottom and narrower at the top, with the tapered shape ranging from (1:10) to (1:5). The outer side of the die fixing sleeve (44) has a taper that is the same size as the inner side of the lower die peripheral fixing sleeve (43); The inner side of the die fixing constraint sleeve (44) has a tapered shape that is narrow at the bottom and wide at the top, with the tapered shape ranging from (1:15) to (1:10). The outer side of the lower mold (10) of the Haval mold body has a taper that is the same size as the inner side of the die fixing constraint sleeve (44).

6. The method for forming eccentric copper-chromium alloy parts by extrusion using a combined Haval die as described in claim 3, characterized in that: Both the first upper mold (20) and the second upper mold (30) of the Haval mold body are connected to the slide block of the stamping machine through the upper mold fixing mechanism (50). The upper mold fixing mechanism (50) includes an upper mold fixing plate (51), and an upper mold fixing block (52) is fixed at the lower end of the upper mold fixing plate (51). The upper mold fixing block (52) has a vertically penetrating upper mold fixing constraint hole (521). The connecting seat (21) of the first upper mold is fixedly constrained in the upper mold fixing constraint hole (521).

7. The method for forming eccentric copper-chromium alloy parts by extrusion using a combined Haval die as described in claim 6, characterized in that: The upper mold fixing mechanism (50) has an upper mold quick change mechanism (53), which includes a quick change mechanism fixing plate (531) fixed at the lower end of the upper mold fixing plate (51). The lower end of the quick change mechanism fixing plate (531) has a plurality of quick change constraint slide grooves (532) extending radially therein. A quick change synchronous slider (533) is slidably connected in the quick change constraint slide groove (532). A sliding connecting column (534) is fixed at the lower end of the quick change synchronous slider (533). The lower end of the quick-change mechanism fixed plate (531) is rotatably connected to a sliding drive plate (535). The sliding drive plate (535) has multiple vertically penetrating sliding drive constraint grooves (536). The sliding drive constraint grooves (536) extend spirally along the plate surface of the sliding drive plate (535), dividing the upper mold fixing block (52) into multiple upper mold fixing partition blocks (520) along its radial plane. The sliding connecting column (534) passes through the sliding drive constraint grooves (536) and is fixedly connected to the upper mold fixing partition blocks (520) one by one. The quick-change mechanism fixed plate (531) is rotatably connected to the outside of the drive plate synchronous ring (537), the drive plate synchronous ring (537) is fixedly connected to the sliding drive plate (535), and the drive handle (538) is fixed to the outside of the drive plate synchronous ring (537).

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