The application of arc stud welding began in 1936 and first appeared in the shipbuilding industry. Due to its advantages of fast, reliable, simple operation and low cost, stud welding technology is relatively mature in western developed countries. More than 80% of stud welding is done by capacitive and arc stud welding machines. of. In recent years, with the rapid and steady improvement of China's economic level, the field of arc-type stud welding technology has become more and more extensive. Many institutions and scholars in China have conducted a lot of research on stud welding technology in various application fields. Wang Kehong used the principle of scattered magnetic field to make the arc rotate along the wall of the stud. A new technology of hollow stud arc welding was proposed. For the hollow stud with outer diameter of 12mm and wall thickness of 3mm, stud welding arc around the stud wall was realized. Uniform rotation, the joint strength can be maintained in the range of 330~390MPa; Chiqiang has developed a stepping arc stud welding gun and its control system, and proposes that the stud can be fed at a low speed while providing sufficient pressing force to achieve the arc. Stud welding, and bending test shows that the stud welding head can meet the requirements of use; Ge Jiaqi brazed Q235 steel stud and 6061 aluminum alloy, using optical microscope, scanning electron microscopy, energy spectrum analysis and other characterization methods, the joint structure The composition and phase composition were analyzed. The mechanical properties test showed that the shear strength of the joint was 65 MPa. Huang Zhilin passed the 0.7mm fund project: Fujian Provincial Department of Education Science and Technology Project A-class production and research special project A13232 Xiamen University of Technology National Fund Research project (XYK201428 plate thickness low carbon steel is supported by corresponding materials for positioning welding, which solves the problem of excessive heat during welding The problem of welding defects and the accuracy of the position of the studs; Liu Zhenguo proposed automatic position detection of each surface of the workpiece before welding, correcting the position of the studs during the welding process, and adding automatic compensation to prevent arcing or Virtual welding defects; Liu Zhiying through the stud welding technology in the 660kW wind turbine ground anchor welding process a lot of production practices, summed up the shortcomings and defects of stud welding, the reasons for the welding joints caused by the welding, proposed Measures to prevent partial welding and improve the quality of welds; in the process of automobile manufacturing, the company uses short-cycle drawn-arc stud welding for automobile roofs and large partitions with a thickness of 0.8~2.0mm to solve the welding strength and efficiency problems. . In this paper, an arc-type stud welding method for passenger car air-conditioning fastener bolts is proposed. The welding mechanism of arc-type stud welding of passenger car air-conditioning bolts is studied. The mechanical stretching of arc-type stud welding is adopted. Channel boring, tapping, bolt pre-embedding and welding, skin repair welding and many other cumbersome processes, so that the passenger car roof overall welding production section air conditioning bolts embedded appearance top cover skin and air conditioning bolt manual arc The appearance of the welding is long, and the welding surface quality of the [02 gas-shielded welding method is poor, the weld is not uniform, and the sealing performance is poor, which ultimately leads to poor flatness of the roof of the passenger car. In order to improve the production cycle and welding quality, this paper proposes to use the arc type stud welding method instead of the original bolt pre-embedded gas shield welding method for the welding of passenger car air-conditioning fixing bolts, and design a stud welding gun that can replace the studs by itself. The overall structure is as shown. The designed bus roof air conditioning stud welding device includes electromagnetic mechanism, arc ignition lifting mechanism, return spring mechanism, automatic feeding mechanism and fixture, etc. The principle of electromagnet is used in the design of the welding torch, and the stud is lifted by the moving iron core. The arc is sent to the molten pool under the action of the restoring force of the spring after the power is cut off. Among them, the design of the automatic feeding mechanism is based on the principle of revolving of the revolver, and it can be used together with the clamp. It can clamp 6 studs at a time. After one stud is welded, adjust the wheel to the next stud by manually turning the wheel. Welding can greatly reduce the stud clamping time and improve the welding efficiency. 2 Build a stud welding as a hardware schematic of the welding platform. Table 1 is a photograph of the appearance of the test piece after welding. (a) It can be seen that there is a slight splash in the weld area between the stud and the skin, but the overall appearance quality is good. It can be seen from the appearance of the back side of the skeleton after the completion of the Ob stud welding experiment that the stud penetrates the skin and is preferably welded to the skeleton. 3 Stud tensile test Air conditioning studs are subjected to both axial and radial forces during passenger car operation. In order to ensure driving safety, studs have certain quality requirements in terms of tensile strength and shear strength. Where the shear strength depends on the strength of the stud material, and the tensile strength after stud welding depends on the tensile strength of the stud weld and the tensile strength of the stud itself, if the stud weld is tensile If the strength is greater than the tensile strength of the stud itself, the stud welding quality is considered to be good. In order to verify the quality of stud welding, a stud welding experimental platform was built, and the stud tensile test was carried out using a universal testing machine in accordance with the tensile test method for welded joints specified in GB/T2651-2008/ISO4136:2001. When the tensile test is performed on the universal material testing machine, the set tension F is calculated as F = nxdVb / 4., and d is the stud diameter, which is the tensile strength of the stud. Calculated by the formula, the tensile force F is 50240N. The stud and the skeleton test piece are respectively clamped by the fixture, and the tensile force value F=50kN is set. The universal tensile tester is used for the stud tensile test, and the welding is performed. The stud is pulled up along the axial force until it breaks. The stud cross-section appearance of the stud welding tensile test is shown. It can be seen from the appearance of the section of the stud. After sufficient deformation, the stud or base metal is broken outside the weld zone, indicating that the welding quality is good. 4 Conclusion 1 For the welding of passenger car air-conditioning fixing bolts, the arc-type stud welding academic parent flow theory / R & D / design / manufacturing method is used to replace the original bolt pre-embedded gas shield welding method, and the studs can be replaced by the studs. The welding torch completes the drawing of 3D CAD drawings. 2 After completing the hardware construction of the stud welding experimental platform, the experiment of arc stud welding was carried out using a stud with a diameter of 10 mm. The welding current was set to 900 A according to the empirical formula, and the welding time was 60 ms. Welding of the column. 3) The stud tensile test was carried out with a universal testing machine, and the welding quality of the stud penetration welding was verified by observing the appearance of the stud section. Wang Kehong, Zhang Deku, Zheng Shixiong, et al. Hollow stud arc welding method. Welding school pool strong, Zhang Jianxun, Fu Jifei, and so on. Low-speed feed of studs in arc stud welding. Journal of Welding, 2005, 26(5): 23-26. Ge Jiaqi, Jiang Yong, Wang Kehong, et al. Wrapped brazing aluminum-steel stud welding joint structure and sex Huang Zhilin, Zhang Liang. An effective way to improve the quality and precision of thin-plate stud welding, Liu Zhenguo, Jin Wufei, Lei Wei, et al. Stainless steel high-voltage switchgear robot stud welding should be Liu Zhiying. The reasons for the partial welding of the stud welding head and its countermeasures. Welding Technology, 2006, 35 (2: 63-64. 耿 éœ èžº. Stud welding process for automotive body parts. Welding, 2004 (11): 42-43. (Editor Coward) coating equipment has been shipped. Oerlikon Barr The head of Chas R&D said: INNOVA is a breakthrough in application technology that combines flexibility and high stability. It has been a key factor in the sales growth of Oerlikon Balzers. “Oerlikon Balzers launched INNOVA 8 years ago. And define a new benchmark for it. Because coating equipment requires a six-figure investment, they should be as flexible as possible. The person in charge added, “The parts and tools that are coated as needed and the diversity of the customer. 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Experimental Study on Arc-type Stud Welding of Bus Air Conditioning Stud
The application of arc stud welding began in 1936 and first appeared in the shipbuilding industry. Due to its advantages of fast, reliable, simple operation and low cost, stud welding technology is relatively mature in western developed countries. More than 80% of stud welding is through capacitive and arc snails.