Welding method for automobile manufacturing
By adjusting welding parameters step by step, the problem of weld defects in dissimilar material welding was solved, achieving efficient and low-cost welding quality improvement, and meeting the dissimilar material welding needs of automobile manufacturing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHANGCHUN ENGLEY MOLD MFG
- Filing Date
- 2026-02-10
- Publication Date
- 2026-04-17
AI Technical Summary
In automobile manufacturing, the welding of dissimilar materials is prone to defects such as incomplete penetration, lack of fusion, weld beads, and burn-through due to inconsistent thickness and angle. These defects affect the welding strength, plasticity, and fatigue life, and the welding quality is difficult to meet the requirements of crash tests, resulting in high rework costs and low efficiency.
A step-by-step welding method is adopted, and welding parameters, including welding speed, wire feed speed and included angle, are adjusted according to the welding temperature changes. The junction between the energy-absorbing box and the base plate is welded in four steps to ensure that the welding parameters of each step are adapted to different angle and temperature changes, and to avoid defects caused by a single parameter.
Improve welding efficiency and forming quality, reduce rework rate, lower costs, ensure first-pass yield rate, save labor time, adapt to welding requirements of dissimilar materials, and produce aesthetically pleasing welds.
Smart Images
Figure CN121870205A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of welding process technology in the automotive manufacturing industry, and particularly relates to a welding method for automobile manufacturing. Background Technology
[0002] In the automotive manufacturing industry, welding is a core assembly process that directly determines the structural strength, safety performance, and production efficiency of a vehicle. With the increasing diversification of car models and the trend towards lightweighting, as well as the widespread use of dissimilar materials such as aluminum alloys and high-strength steel in car body manufacturing, welding is becoming increasingly important.
[0003] Currently, when welding a single weld seam in products such as subframes and bumpers produced in the field of aluminum alloy welding, a single welding parameter is used. Due to inconsistencies in the thickness of the base material and the welding angle, welding defects such as incomplete penetration, lack of fusion, weld beads, and burn-through can occur, significantly reducing the strength, plasticity, and fatigue life of the weld and failing to meet welding performance requirements.
[0004] Car bumpers are classified as D-characteristic products (D refers to safety characteristics). To meet product performance requirements, customers conduct bench and full-vehicle crash tests during various stages of vehicle development, including side pole impact, frontal impact, and offset impact. These tests are performed at different phases, such as the vehicle pilot production stage (VFF stage), the mass production pilot stage (PVS stage), and the initial production run stage (OS stage). Therefore, the welding quality of each weld is extremely important. During crash tests, failures due to weld defects are not uncommon. Furthermore, crash tests are expensive, and the causes and analysis of failures require extensive documentation.
[0005] In actual production, taking the welding of energy-absorbing boxes as an example, the bottom ends of the four sides of the energy-absorbing box are welded to the base plate using a single weld seam, with the entire weld seam using the same welding parameters. However, due to the different angles formed between the four sides and the base plate, welding with the same parameters will cause welding defects such as incomplete fusion, incomplete welding, weld beads, and burn-through, resulting in low welding quality, a high repair rate, and a significant increase in labor costs. At the same time, defects such as incomplete penetration, incomplete fusion, and cracks will significantly reduce the tensile strength and fatigue strength of the weld seam; during continuous welding, excessive heat input can easily lead to coarse grains, reducing the impact toughness of the weld seam, causing a decline in the mechanical properties after welding, poor weld formation, and affecting the appearance and visual impact of the weld seam. Summary of the Invention
[0006] In view of this, the present invention aims to provide a welding method for automobile manufacturing that improves welding efficiency, optimizes welding costs, reduces rework rate, achieves a high first-pass welding qualification rate, eliminates the need for repeated welding repairs, grinding, or re-welding, and saves labor time.
[0007] To achieve the above objectives, the technical solution created by this invention is implemented as follows: A welding method for automobile manufacturing, used for one-time welding of the junction between the side end of the welding body and the body to be welded, includes the following steps: S1: Weld along the junction of the bottom end of the first side of the welding body and the welded body, with a welding speed of 50cm / min, the first side of the welding body being perpendicular to the welded body, and the weld angle being 90°. S2: After step S2 is completed, continue welding along the junction of the bottom of the second side of the welding body and the welded body. The welding speed is 60cm / min, the angle between the second side of the welding body and the welded body is less than 90°, and the weld angle is 80°. S3: After step S3 is completed, continue welding along the junction of the bottom of the third side of the welding body and the welded body. The welding speed is 65cm / min. The third side of the welding body is perpendicular to the welded body, and the weld angle is 90°. S4: After step S3 is completed, continue welding along the junction of the bottom of the fourth side of the welding body and the welded body. The welding speed is 70cm / min. The angle formed between the fourth side of the welding body and the welded body is greater than 90°, and the weld angle is 100°.
[0008] Furthermore, the vertical distance between the bottom end of the first side and the corresponding edge on the welded body is less than the vertical distance between the bottom end of the second side and the corresponding edge on the welded body, the vertical distance between the bottom end of the third side and the corresponding edge on the welded body, and the vertical distance between the bottom end of the fourth side and the corresponding edge on the welded body.
[0009] Furthermore, in step S1, the welding wire feed speed is 500 cm / min, the arc length correction is -5, the welding push angle is 80°, and the welding included angle is 45°.
[0010] Furthermore, in step S2, the welding wire feed speed is 600 cm / min, the arc length correction is -10, the welding push angle is 75°, and the welding included angle is 40°.
[0011] Furthermore, in step S3, the welding wire feed speed is 480 cm / min, the arc length correction is 0, the welding push angle is 70°, and the welding included angle is 45°.
[0012] Furthermore, in step S4, the welding wire feed speed is 480 cm / min, the arc length correction is +5, the welding push angle is 70°, and the welding included angle is 45°.
[0013] Compared with the prior art, the present invention can achieve the following beneficial effects: (1) The welding method described in this invention divides a weld into four steps. The welding current changes with the temperature during the welding process, which avoids the welding defects such as lack of fusion, incomplete welding, weld beads, and burn-through that are easily caused by using only one welding parameter to weld a weld in the prior art.
[0014] (2) This invention improves welding efficiency, optimizes welding costs, reduces rework rate, and achieves a high first-time welding pass rate. It eliminates the need for repeated welding, grinding, or re-welding, saving labor time. (3) The present invention creates stable welding parameters and controllable welding speed, thus avoiding downtime caused by fluctuations in welding parameters that affect production efficiency.
[0015] (4) The welding formed by the method described in this invention is beautiful, and the welding process parameters with appropriate parameters will present a neat fish scale pattern weld when welding aluminum alloy. Attached Figure Description
[0016] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A schematic diagram of the welding direction for welding the energy-absorbing box and the base plate in the welding method for automobile manufacturing described in an embodiment of the present invention; Figure 2 A schematic diagram of the structure of the energy-absorbing box and the base plate after welding according to the welding method for automobile manufacturing described in the embodiment of the present invention; Figure 3 for Figure 2 Rear view; Figure 4 for Figure 2 Side view.
[0017] Explanation of reference numerals in the attached figures: 1. Energy-absorbing box; 2. Base plate; 3. First side; 4. Second side; 5. Third side; 6. Fourth side. Detailed Implementation
[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.
[0019] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.
[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.
[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0022] The invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0023] like Figure 1 As shown, a welding method for automobile manufacturing involves welding the junction between the side end of a welding body and the body to be welded in one step. The welding body is an energy-absorbing box 1, and the body to be welded is a base plate 2. The welding is performed using a FANUC welding robot and powered by a FENNES welding power supply. The method includes the following steps: S1: Continue welding along the junction of the bottom end of the first side 3 of the energy-absorbing box 1 and the base plate 2. The vertical distance between the bottom end of the first side 3 and the base plate 2 is smaller than the vertical distance between the other sides and the base plate 2. The first side 3 of the energy-absorbing box 1 is perpendicular to the base plate 2. The welding speed is 50cm / min, the weld angle is 90°, the welding wire feed speed is 500cm / min, the arc length correction is -5, the welding push angle is 80°, and the welding included angle is 45°. Step S1 involves welding along the first side 3 from the beginning to the end; S2: After welding in step S2 is completed, switch the parameters as follows: welding speed is 60cm / min, the angle between the second side 4 of the energy-absorbing box 1 and the base plate 2 is less than 90°, weld angle is 80°, welding wire feed speed is 600cm / min, arc length correction is -10, welding push angle is 75°, and welding included angle is 40°; continue welding along the junction of the bottom end of the second side 4 of the energy-absorbing box 1 and the base plate 2 according to the above parameters. Weld to the tail end of the first side 3, adjust the welding parameters, and continue welding from the head end to the tail end of the second side 4. This welding process is continuous and does not stop. The weld angle in this process is 80°, which requires greater arc heat to meet the welding quality. Since the welding of the area to be welded has been completed in step S1, the welding temperature has increased, and the welding speed should not be too slow to prevent welding defects such as burn-through and weld beads. Therefore, the welding speed needs to be adjusted to 60cm / min. S3; After welding is completed in step S3, switch the parameters as follows: welding speed is 65cm / min, the third side 5 of the energy-absorbing box 1 is perpendicular to the base plate 2, the weld angle is 90°, the welding wire feed speed is 480cm / min, the arc length correction is 0, the welding push angle is 70°, and the welding included angle is 45°; continue welding along the junction of the bottom end of the third side 5 of the energy-absorbing box 1 and the base plate 2 according to the above parameters. Weld to the tail end of the second side 4, adjust the welding parameters, and continue welding from the head end to the tail end of the third side 5. This welding process is continuous and does not stop. S4: After welding in step S3 is completed, switch the parameters as follows: welding speed is 70cm / min, the angle between the fourth side 6 of the energy-absorbing box 1 and the base plate 2 is greater than 90°, weld angle is 100°, welding wire feed speed is 480cm / min, arc length correction is +5, welding push angle is 70°, welding angle is 45°, and welding speed is 50cm / min; continue welding along the junction of the bottom end of the fourth side 6 of the energy-absorbing box 1 and the base plate 2 according to the above parameters. Weld to the tail end of the third side 5, adjust the welding parameters, and continue welding from the head end to the tail end of the fourth side 6. This welding process is continuous and does not stop. When welding the tail end of the fourth side 6, the weld seam coincides with the head end of the first side 3, that is, a square ring structure is formed along the weld seam between the bottom end of the energy-absorbing box 1 and the base plate 2.
[0024] After welding is completed, as follows Figure 2-4As shown, the energy-absorbing box 1 and the base plate 2 are welded together by a single weld. The weld parameters on the corresponding first side 3, second side 4, third side 5 and fourth side 6 of the same weld are all different. The included angles between the first side 3 and the third side 5 of the energy-absorbing box 1 and the base plate 2 are both 90°, the included angle between the second side 4 and the base plate 2 is 80°, and the included angle between the fourth side 6 and the base plate 2 is 100°.
[0025] The vertical distance between the bottom of the first side 3 and the corresponding edge of the base plate 2 is 15mm; the vertical distance between the bottom of the second side 4 and the corresponding edge of the base plate 2 is 50cm; the vertical distance between the bottom of the third side 5 and the corresponding edge of the base plate 2 is 35cm; and the vertical distance between the bottom of the fourth side 6 and the corresponding edge of the base plate 2 is 64cm.
[0026] The welding method of this invention produces products suitable for bench testing and vehicle testing, with a high first-pass yield, saving significant costs associated with secondary testing and reducing the need for extensive collision failure analysis reports and documentation.
[0027] The welding method of this application involves four steps in welding a single weld. In each step, the welding current changes with the temperature during the welding process. This avoids the common problem in existing technologies where only one welding parameter is used to weld the entire weld. It improves welding efficiency, optimizes welding costs, reduces rework rate, and achieves a high first-pass yield. It eliminates the need for repeated welding, grinding, or re-welding, saving labor time. Stable welding parameters and controllable welding speed prevent downtime caused by fluctuations in welding parameters, thus avoiding impacts on production efficiency.
[0028] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.
[0029] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.
Claims
1. A welding method for automobile manufacturing for one-time welding forming of a joint between a side end portion of a main body and a welded main body, characterized by: Includes the following steps: S1: Weld along the junction of the bottom end of the first side of the welding body and the welded body, at a welding speed of 50cm / min, with the first side of the welding body perpendicular to the welded body and the weld angle being 90°. S2: After step S2 is completed, continue welding along the junction of the bottom end of the second side of the welding body and the welded body. The welding speed is 60cm / min, the angle between the second side of the welding body and the welded body is less than 90°, and the weld angle is 80°. S3: After step S3 is completed, continue welding along the junction of the bottom end of the third side of the welding body and the welded body. The welding speed is 65cm / min. The third side of the welding body is perpendicular to the welded body, and the weld angle is 90°. S4: After step S3 is completed, continue welding along the junction of the bottom of the fourth side of the welding body and the welded body. The welding speed is 70cm / min, the angle formed between the fourth side of the welding body and the welded body is greater than 90°, and the weld angle is 100°.
2. The welding method for automobile manufacturing according to claim 1, characterized in that: The vertical distance between the bottom end of the first side and the corresponding edge of the welded body is less than the vertical distance between the bottom end of the second side and the corresponding edge of the welded body, the vertical distance between the bottom end of the third side and the corresponding edge of the welded body, and the vertical distance between the bottom end of the fourth side and the corresponding edge of the welded body.
3. The welding method for automobile manufacturing according to claim 2, characterized in that: In step S1, the welding wire feed speed is 500 cm / min, the arc length correction is -5, the welding push angle is 80°, and the welding included angle is 45°.
4. The welding method for automobile manufacturing according to claim 2, characterized in that: In step S2, the welding wire feed speed is 600 cm / min, the arc length correction is -10, the welding push angle is 75°, and the welding included angle is 40°.
5. The welding method for automobile manufacturing according to claim 2, characterized in that: In step S3, the wire feeding speed is 480 cm / min, the arc length correction is 0, the welding push angle is 70°, and the welding included angle is 45°.
6. The welding method for automobile manufacturing according to claim 2, characterized in that: In step S4, the welding wire feed speed is 480 cm / min, the arc length correction is +5, the welding push angle is 70°, and the welding included angle is 45°.