Computer-aided Numerical Analysis Of The Arc Welding Process For The Pole-structure

Welding technology is used more and more widely in modern industrial manufacture, so that the quality to the welding workpiece is demanded much higher. Since the welding of pole-structure is huge in quantity and there are much technical problems to be solved, the welding procedure of the pole-structure made by A3 steel is analyzed in this paper by using FEM.In the paper, the entities of the welding model are set up by APDL command in the universal FEM analysis software ANSYS. And the appropriate finite element model has been constructed by the non-uniform mesh. For the lacking of the material properties at high temperature, the experimental relations were adopted to describe the data varying with the temperature. The heat enthalpy was used to simulate the phase change during the welding. And the bi-ellipse Gauss and the bi-ellipse-sphere heat sources were applied to describe the moving welding heat source together. The numerical analyses of the transient heat process and the elastic-plastic structure have been carried out.In accordance with the coupled-field function of ANSYS, the direct and sequential coupled methods were executed respectively to analyze the welding. The computational results show that the structure field is strongly influenced by the heat field, but weakly reversed. And the selection of the element type is important, because it will affect the convergence and the results. By contrasting the results from two coupled methods, the sequential coupled method is adopted finally to solve the welding problem. After calculating, the change of the temperature, stress and the structure deformation in three-dimension during welding have been simulated.The comparison between the computational and experimental results shows that the temperature distributions and the trend of the deformation are nearly identical, and the stress computed can be accepted for the pole-structure during welding, which indicates the availability of the analytic method proposed in this paper. It establishes the foundation of the analysis to the pre-welding and post-welding treatments on the pole-structure.