Structure Design Of An Automatic Machine For Vertical Fillet Welding

In the industry of ship building, engineering machinery, coal mine machinery, stereo garage, bridge manufacturing and so on, fillet welding in the vertical position has always been a significant part, so the welding quality and automaticity have direct impact on the quality and productivity of weldments. While fillet welding in the vertical position has always been a welding difficulty, the quality control of which is more difficult than vertical position welding and fillet welding. It’s one of the important factors that affect the development of automatic welding production lines. The vertical fillet welding machines have the defects of low automatic degree, large welding head, difficult adjustment, low productive and flexibility in the condition of existing technology. So the research of welding process and machine of fillet welding in the vertical position has its theoretical and practical significance. The main research contents are as follows:(1) By using the method of finite element non-linear transient thermal analysis, contrastive analysis about T-type weldments temperature field change with different welding torch slope was done. To improve the solution accuracy, material heat property parameters non-linear and transition mesh was used, with “birth and death” method temperature field was simulated, and taking the influence of welding torch slope into consideration, the heat source model was amended.(2) With MAG welding technology, the research of fillet welding in the vertical position was done through experimental analysis. T-type weldments were taken for the experiment objects, which are 5mm and 10 mm thick respectively. And then the weld forming impacts of different welding processes(different welding directions, swing modes, especially the position of welding torch) were discussed and analyzed.(3) According to the existing problems of welding machine and experimental analysis in welding process needs, two schemes of automatic welding machines were proposed. From the perspectives of freedom of the machine, property, productivity, degree of flexibility and cost, comprehensive comparative analysis of the two schemes was done. Then the scheme of the machine with four-rotatable welding heads was chosen, and specification parameters of the machine were ascertained.(4) The key components and their working principles were analyzed, design and selection of main mechanical structures accomplished, and then the 3-D model was established. By using servo cylinder as the power source, automatic adjustment of the welding torch slope and flexible welding realized. Mathematical model of the welding torch position was established to analyze and solve, by using servo cylinder to adjust the welding torch position, adjustment of the welding wire and weld was realized automaticly. The flexible alignment mechanism can ensure that the welding wire aligns to the weld. Eventually, 3-D simulate demonstration model was established by the technology of animation simulation to display the design scheme and work procedure of the welding machine visually.