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CN-122007598-A - Rear frame manufacturing method and rear frame

CN122007598ACN 122007598 ACN122007598 ACN 122007598ACN-122007598-A

Abstract

The application discloses a rear frame manufacturing method and a rear frame, wherein the manufacturing method comprises the steps of 100, conducting block design on rear frame parts to obtain a plurality of part blocks, 200, optimizing welding seam shapes among the part blocks according to the part blocks, wherein the welding seam is an arc welding seam, 300, conducting laser blanking or blanking die blanking according to the outline and the size of the optimized part blocks to obtain plate material blocks, 400, connecting the plate material blocks through laser splice welding to obtain rear frame plates, 500, conducting heat treatment on the rear frame plates, 600, conducting integral hot stamping on the rear frame plates after heat treatment to obtain the rear frame, and 700, detecting the molding accuracy of the rear frame. The production efficiency of the automobile parts is improved, the production cost is reduced, and the collision performance and the light weight level of the parts are improved.

Inventors

  • LI CHUNGUANG
  • MA WENYU
  • ZHANG WEI
  • PAN YUE
  • LIU LIXIAN
  • HE LANG

Assignees

  • 首钢集团有限公司

Dates

Publication Date
20260512
Application Date
20260304

Claims (10)

  1. 1. A method of manufacturing a rear frame, the method comprising: step 100, carrying out block design on rear frame parts to obtain a plurality of part blocks; step 200, optimizing the shape of a welding seam among the part blocks aiming at the part blocks, wherein the welding seam is an arc welding seam; Step 300, obtaining plate material blocks by adopting laser blanking or blanking by a blanking die according to the profile and the size of the optimized part blocks; Step 400, connecting the plate blocks through laser splice welding to obtain a rear frame plate; step 500, performing heat treatment on the rear frame plate; step 600, integrally hot stamping the heat-treated rear frame plate material to obtain a rear frame; And 700, detecting the molding precision of the rear frame.
  2. 2. The method of manufacturing a rear frame of claim 1, wherein step 200, the part segments optimizing a weld shape between the part segments comprises: step 211, numbering a plurality of welding seams according to the distribution of the parts in blocks to form 1-N numbers, wherein N is an integer larger than 1; Step 212, simulating the maximum thinning rate of the straight-line weld after hot stamping from the weld joint No.1, wherein the thinning rate is equal to the thinning amount/the original thickness; 213, adjusting the offset h of the arc-shaped welding seam by taking 1mm as a gradient, and simulating the corresponding thinning rate after each adjustment, wherein the offset h is the arc-shaped height of the arc-shaped welding seam by taking the straight line of the straight line welding seam as a reference; Step 214, selecting the shape of the welding seam corresponding to the minimum thinning rate as the final shape of the welding seam No. 1; Step 215, the step 212-step 214 are repeated in sequence corresponding to the weld joints No. 2-N.
  3. 3. The method according to claim 2, wherein in step 213, the offset h of the arc-shaped weld is adjusted with a gradient of 1mm, the length of the straight-line weld is L, and the value of the offset h ranges from-L/2 to L/2.
  4. 4. The method of manufacturing a rear frame of claim 1, wherein step 200, the part segments optimizing a weld shape between the part segments comprises: 221, numbering a plurality of welding seams according to the distribution of the parts in blocks to form 1-N numbers, wherein N is an integer larger than 1; Step 222, starting from the weld joint No. 1, simulating the thinning rate when the offset h=0, h=l/2, h= -L/2, h=l/4, h= -L/4, wherein L is the length when the weld joint No. 1 is a straight line weld joint, the offset h is the arc height of the arc-shaped weld joint based on the straight line where the straight line weld joint is located, and the thinning rate= |thinning amount/original thickness|; Step 223, selecting the offset h corresponding to the minimum two thinning rates, setting the offset h as h1 and h2, and calculating an intermediate value h3 between h1 and h 2; Step 224, calculating an intermediate value h4 between h1 and h3 and an intermediate value h5 between h2 and h3, and simulating the thinning rates of h1, h2, h3, h4 and h 5; Step 225, repeating step 223 and step 224 until the difference between the two minimum thinning rates is less than or equal to 1%, and selecting the intermediate value of the two offset amounts h corresponding to the two thinning rates as the final shape of the No. 1 weld; step 226, the steps 222-225 are repeated in sequence corresponding to the weld joints No. 2-N.
  5. 5. The method of manufacturing a rear frame as set forth in any one of claims 1 to 4, wherein the plurality of component blocks includes a left side member, a right side member, a front cross member, a center cross member, and a rear cross member, the left side member and the right side member extending longitudinally and being disposed at a lateral interval, the front cross member, the center cross member, and the rear cross member being disposed between the left side member and the right side member, the front cross member, the center cross member, and the rear cross member each extending laterally and being disposed at a longitudinal interval.
  6. 6. The method according to claim 5, wherein the right side member and the left side member are made of CR950/1300HS+AS material and have a thickness of 1.4mm, the rear cross member is made of 1000HS+AS material and has a thickness of 1.0mm, the middle cross member is made of 1000H+AS material and has a thickness of 1.2mm, and the front cross member is made of 1000H+AS material and has a thickness of 0.8mm.
  7. 7. The method according to claim 5, wherein in step 400, when the plate material is split-welded by laser, a patch plate is fixed to the blanks of the left side member and the right side member by spot welding before or after the split welding, the patch plate is made of CR950/1300HS+AS material, the thickness is 1.2mm, and the spot welding position avoids the weld joint region.
  8. 8. The method of manufacturing a rear frame as set forth in claim 1, wherein the heat treating of the rear frame plate in step 500 includes placing the rear frame plate in a heating furnace and maintaining the temperature at 850-950 ℃ for 3-10min.
  9. 9. The method of manufacturing a rear frame as set forth in claim 1, wherein the step 700 of detecting the molding accuracy of the rear frame includes detecting the shape accuracy of the critical assembly surface and the stress portion of the part with a dedicated detecting device, wherein the standard error allowable range is ±0.5mm, calculating an out-of-tolerance coefficient d1= (|actual error value| -0.5)/0.5 if the out-of-tolerance coefficient d1= (|) actual error value| -0.5)/0.5, adjusting the heating temperature T1 of the step 500 according to the formula t1=930+ (1+d1) x 10, and T1 is not more than 950 ℃, and then re-executing the steps 500 to 700.
  10. 10. A rear frame manufactured using the rear frame manufacturing method as claimed in any one of claims 1 to 9.

Description

Rear frame manufacturing method and rear frame Technical Field The application belongs to the technical field of vehicle part manufacturing, and particularly relates to a rear frame manufacturing method and a rear frame. Background The number of parts of the traditional rear frame assembly is up to more than ten, and after each part is punched independently, the parts are connected together in a welding mode. Therefore, in the conventional production process, 10 sets of stamping dies and corresponding detectors are required to be designed. And meanwhile, the single stamping production and storage are required, and then the welding is performed. The welding is usually carried out in a spot welding mode, the position of the welding point is easy to become a stress concentration position, the automobile is invalid in service and collision, and the problems of low production efficiency and high production cost exist. Disclosure of Invention The present application aims to solve at least one of the technical problems existing in the prior art. Therefore, the application provides a rear frame manufacturing method and a rear frame, which improve the production efficiency of automobile parts, reduce the production cost and improve the collision performance and the light weight level of the parts. In a first aspect, the present application provides a method for manufacturing a rear frame, the method comprising: step 100, carrying out block design on rear frame parts to obtain a plurality of part blocks; step 200, optimizing the shape of welding seams among the part blocks aiming at the part blocks, wherein the welding seams are arc welding seams; step 300, obtaining plate material blocks by adopting laser blanking or blanking by a blanking die according to the outline and the size of the optimized part blocks; step 400, connecting the plate blocks through laser splice welding to obtain a rear frame plate; Step 500, performing heat treatment on the rear frame plate; step 600, integrally hot stamping the heat-treated rear frame plate material to obtain a rear frame; and 700, detecting the molding precision of the rear frame. According to the rear frame manufacturing method, the problems of a large number of parts, low production efficiency, high production cost, poor collision performance and the like in the traditional rear frame manufacturing are effectively solved through a series of steps of block design, arc welding seam optimization, accurate blanking, laser welding, reasonable heat treatment, integral hot stamping, strict precision detection and the like. Compared with the traditional manufacturing method, the method reduces the number of parts, reduces the investment cost of the die and the checking fixture, improves the strength and toughness of the welding seam by adopting the arc welding seam, further improves the collision performance of the rear frame, integrally forms an integral structure by hot stamping, reduces the assembly process and assembly errors, and improves the integral precision and reliability of the rear frame. Meanwhile, the production efficiency is improved due to the optimized design of each step, the production cost is reduced, the weight of the rear frame is reduced, and the development requirement of modern automobile manufacturing is met. According to one embodiment of the application, step 200, part segmentation optimizing the shape of the weld between part segments includes: step 211, numbering a plurality of welding seams according to the distribution of the part blocks to form 1-N numbers, wherein N is an integer larger than 1; Step 212, simulating the maximum thinning rate of the straight-line weld after hot stamping from the weld joint No.1, wherein the thinning rate is equal to the thinning amount/the original thickness; 213, adjusting the offset h of the arc-shaped welding seam by taking 1mm as a gradient, and simulating the corresponding thinning rate after each adjustment, wherein the offset h is the arc-shaped height of the arc-shaped welding seam by taking the straight line of the straight line welding seam as a reference; Step 214, selecting the shape of the welding seam corresponding to the minimum thinning rate as the final shape of the welding seam No. 1; Step 215, the step 212-step 214 are repeated in sequence corresponding to the weld joints No. 2-N. According to an embodiment of the present application, in step 213, the offset h of the arc-shaped weld is adjusted with a gradient of 1mm, the length of the straight-line weld is L, and the value of the offset h ranges from-L/2 to L/2. According to one embodiment of the application, step 200, part segmentation optimizing the shape of the weld between part segments includes: 221, numbering a plurality of welding seams according to the distribution of the part blocks to form 1-N numbers, wherein N is an integer larger than 1; Step 222, starting from the weld joint No. 1, simulating the thinning rate when the offset h=0,