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CN-122007809-A - Multi-material composite forming process for door frame

CN122007809ACN 122007809 ACN122007809 ACN 122007809ACN-122007809-A

Abstract

The invention discloses a multi-material composite forming process of a vehicle door frame, which adopts a multi-material partition matching design and completes forming through a closed-loop continuous processing line, and comprises the following steps of S1, raw material pretreatment, feeding, uncoiling, leveling, tension elimination and thickness detection of coiled materials of different materials, S2, parametric roll forming, progressive rolling and real-time precision straightening of the pretreated raw materials through multi-axis servo roll pressing lines, S3, on-line laser cutting, fixed-length cutting and cutting surface treatment of a formed workpiece, S4, precise punching, stamping and hole position detection of a workpiece mounting hole, S5, flanging and shaping detection of the workpiece end by a numerical control oil pressure punch, S6, detection and warehousing, full detection and precise detection by a special gauge and precise measurement device, and warehousing after rust prevention treatment. The invention completely meets the composite design requirement of multiple materials and ensures the forming consistency from the source.

Inventors

  • LENG QIUBO

Assignees

  • 上海敏孚汽车饰件有限公司

Dates

Publication Date
20260512
Application Date
20260211

Claims (10)

  1. 1. The multi-material composite forming process for the door frame is characterized in that a multi-material partition matching design is adopted, and the forming is completed through a closed-loop continuous processing line, and comprises the following steps: s1, raw material pretreatment, namely feeding, uncoiling, leveling, tension eliminating and thickness detecting are carried out on coiled materials with different materials; S2, parametric roll forming, namely gradually rolling and real-time precision straightening are carried out on the pretreated raw materials by adopting multi-axis servo roller pressing lines; S3, online laser cutting, namely performing fixed-length cutting and cutting surface treatment on the formed workpiece; s4, precisely punching, namely finishing punching and hole position detection of the workpiece mounting hole through a numerical control punch; S5, flanging and shaping, namely carrying out flanging processing and shaping detection on the end part of the workpiece by adopting a numerical control oil pressure punch; s6, detecting and warehousing, namely finishing full detection and accurate detection through a special detection tool and accurate measurement equipment, and warehousing after rust-proof treatment; The closed-loop continuous processing line is formed by connecting core processing equipment through a servo synchronous conveying mechanism, and a workpiece anti-deformation lifting tool is arranged in the conveying process.
  2. 2. The composite molding process of the door frame made of multiple materials is characterized in that the multi-material partition matching design is specifically that a non-bearing area is made of 1.0mm thick DC01 low-carbon steel, a secondary bearing area is made of 1.2mm thick B340LA low-alloy high-strength steel, and a core bearing area is made of 1.5mm thick HC420LA high-strength steel.
  3. 3. The composite molding process of the door frame made of multiple materials according to claim 1, wherein the core processing equipment comprises a 50-axis servo roller pressing line, a 1500W fiber laser cutting machine, a five-axis numerical control punch press, a 15T numerical control oil hydraulic punch press, a three-coordinate measuring instrument and a four-in-one special gauge for a door frame, the 50-axis servo roller pressing line is provided with an adjustable pressure module and 12 sections of general molding rollers, the precision of the three-coordinate measuring instrument is 0.001mm, and the conveying speed of a servo synchronous conveying mechanism is adjustable between 0 m/min and 6 m/min.
  4. 4. The composite molding process of the door frame made of multiple materials according to claim 1, wherein in the raw material pretreatment, a three-station hydraulic uncoiler is adopted for raw material feeding, an expanding chuck is arranged on the uncoiler, the adjusting range of the expanding force of the chuck is 60-80kN, a 24-roller precision leveling machine is adopted for uncoiling and leveling, the upper roller gap of the leveling machine is adjusted according to the thickness of the raw material, the adjusting tolerance is +/-0.02- +/-0.03 mm, the rotating speed of a lower roller is 3-5M/min, and the planeness of the raw material after leveling is less than or equal to 0.15mm/M.
  5. 5. The composite molding process of the door frame made of multiple materials according to claim 1, wherein in the pretreatment of raw materials, a closed loop or adjustable tension control system is adopted for tension elimination, the applied tension is 12-15kN, the tension fluctuation is less than or equal to +/-0.5- +/-0.8 kN, an online laser thickness gauge or a handheld thickness gauge is adopted for raw material detection, and the raw material thickness deviation is directly removed when the deviation exceeds +/-0.02 mm.
  6. 6. The process for composite molding of multiple door frames according to claim 1, wherein in the parametric roll molding, the working pressure of a hydraulic system of a 50-axis servo roller wire is preheated to 20MPa, the temperature of a roller is controlled to 25-35 ℃ by a water cooling system, differential rolling parameters are set for three different materials, wherein the DC01 rolling pressure is 85-90MPa, the rolling speed is 5m/min, the B340LA rolling pressure is 105-110MPa, the rolling speed is 4m/min, the HC420LA rolling pressure is 135-140MPa, and the rolling speed is 3m/min.
  7. 7. The multi-material composite forming process of the door frame according to claim 1, wherein in the parametric roll forming, 12 sections of general forming rollers divide work according to 'front 3 sections of leveling, middle 6 sections of section forming and rear 3 sections of finishing and straightening', the finishing and straightening is provided with a double-laser displacement sensor, the straightness and the torsion of the door frame are detected in real time, the detection frequency is 10 times/second, the straightness and the torsion of the door frame after forming are less than or equal to 0.5mm/M, and the tolerance of the section size is less than or equal to +/-0.2 mm.
  8. 8. The multi-material composite forming process of the door frame is characterized in that in the online laser cutting, a pneumatic linkage positioning clamp or a quick-change positioning clamp is adopted to position a workpiece, the positioning repetition precision is less than or equal to 0.05-0.06mm, the clamping force is 6-8kN, the laser cutting parameters are that the cutting power is 1000-1200W, the cutting speed is 2.5-3m/min, the auxiliary gas is nitrogen, the pressure is 0.7-0.8MPa, the focal position is 0.5mm below the upper surface of the workpiece, the length tolerance of the workpiece after cutting is controlled to be +/-0.3 mm, and the end burr height is less than or equal to 0.05mm.
  9. 9. The composite molding process of the door frame multi-material according to claim 1, wherein the precise punching adopts a phi 8mm and phi 10mm precise punching die, the die clearance is adjusted to be 0.04-0.055mm, the punching speed is 10-15 times/min, the punching force is 75-100kN, the punching sequence is 'small hole first, large hole later, front end part later and middle', the hole position detection adopts a visual detection system or a hand-held hole position detection gauge, the hole position tolerance is less than or equal to 0.1mm, and the hole diameter tolerance is +/-0.02 mm.
  10. 10. The composite molding process of the door frame and the materials is characterized by being suitable for single-frame large-scale continuous production or four-frame small-batch multi-batch alternate production, wherein when the small-batch multi-batch production is performed, a fixture and a die adopt a toolless quick-change structure, the time for changing the die is less than or equal to 28 minutes, the first part after the die is fully checked by a special checking tool and a three-coordinate measuring instrument and then is produced in batches, when the die is detected and put in storage, the precise detection is performed according to batch sampling, the sampling proportion is that 5 parts are extracted every 200 parts or 3 parts are extracted every 50 parts, and all detection data are automatically stored to form a batch quality report.

Description

Multi-material composite forming process for door frame Technical Field The invention relates to the field of automobile door frames, in particular to a multi-material composite forming process of an automobile door frame. Background The automobile door frame is used as a key bearing and decorating part of an automobile body, and directly influences the assembly precision, the structural strength, the sealing performance and the whole automobile safety of the automobile door, and the processing quality and the production efficiency of the automobile door frame have important influences on the mass production, the cost control and the product competitiveness of the automobile manufacturing industry. In order to meet the dual requirements of strength and light weight of different parts of the car door frame, the existing door frame is generally designed by adopting a multi-material combination, specifically, DC01 low-carbon steel is used for a non-bearing area, B340LA low-alloy high-strength steel is used for a secondary bearing area, HC420LA high-strength steel is used for a core bearing area, and the optimal balance of structural performance and light weight is realized through material differentiation collocation. However, the current processing technology for the multi-material combined door frame still has obvious defects, and is difficult to adapt to design requirements and production requirements, and the specific defects are as follows: Firstly, the suitability of material switching is poor, because the strength difference of three steels of DC01, B340LA and HC420LA is large, the roll forming parameters (pressure and speed) of the prior art cannot be commonly used, and when the steel with different strengths is switched and processed, the section size deviation is easy to occur, and the forming quality of a door frame is influenced; secondly, the working procedures are dispersed, core working procedures such as roll forming, laser cutting, precise punching, flanging and shaping are independently carried out, a workpiece is required to be transported for multiple times, deformation is easy to occur in the transportation process, the straightness and torsion precision (the design requirement is less than or equal to 0.5 mm/M) of the door frame are further affected, and the high-precision processing requirement is difficult to meet; Thirdly, the special tool input amount is large, the front left, front right, back left and back right door frames are required to be independently designed with the forming roller and the tool clamp, no generalized part exists, the transformation period is too long (usually more than or equal to 2 hours), the production efficiency is reduced, and the tool input and the production cost are greatly increased. Therefore, a person skilled in the art provides a multi-material composite molding process for a door frame to solve the problems set forth in the background art. Disclosure of Invention In order to solve the technical problems, the invention provides a multi-material composite molding process for a vehicle door frame, which adopts multi-material partition matching design and completes molding through a closed-loop continuous processing line, and comprises the following steps: s1, raw material pretreatment, namely feeding, uncoiling, leveling, tension eliminating and thickness detecting are carried out on coiled materials with different materials; S2, parametric roll forming, namely gradually rolling and real-time precision straightening are carried out on the pretreated raw materials by adopting multi-axis servo roller pressing lines; S3, online laser cutting, namely performing fixed-length cutting and cutting surface treatment on the formed workpiece; s4, precisely punching, namely finishing punching and hole position detection of the workpiece mounting hole through a numerical control punch; S5, flanging and shaping, namely carrying out flanging processing and shaping detection on the end part of the workpiece by adopting a numerical control oil pressure punch; s6, detecting and warehousing, namely finishing full detection and accurate detection through a special detection tool and accurate measurement equipment, and warehousing after rust-proof treatment; The closed-loop continuous processing line is formed by connecting core processing equipment through a servo synchronous conveying mechanism, and a workpiece anti-deformation lifting tool is arranged in the conveying process. The multi-material partition matching design is particularly characterized in that a non-bearing area adopts 1.0mm thick DC01 low-carbon steel, a secondary bearing area adopts 1.2mm thick B340LA low-alloy high-strength steel, and a core bearing area adopts 1.5mm thick HC420LA high-strength steel. Preferably, the core processing equipment comprises a 50-axis servo roller pressing line, a 1500W optical fiber laser cutting machine, a five-axis numerical control punch press, a 15T numerical control