Finite element analysis of pipe discontinuous and continuous butt welding

Temperature and residual stress fields of industrial pipe discontinuous and continuous butt welding was simulated by ABAQUS. The physital properties of the material depead on the temperature, and the effects of environmental conditions on welding temperature filed, which were both considered in simulation. The heat amplitude curves loading method was applied to simulate the moving heat source. The multi-pass welding was simulated by the technique of element birth and death. A comparison of temperature and residual stress fields between discontinuous and continuous welding was carried out.Results indicated that the temperature was much lower while discontinuous welding, but lower axial residual stress can be gained by continuous welding.The annular stress of discontinuous and continuous welding did not have much affection for the pipeline. In addition, the temperature and residual stress field of starting welding point was analyzed. The inner wall residual stress was much higher in starting welding point.