【摘要】 利用轴对称模型研究了大型电机转子焊接残余应力分布规律 ,探讨了单层单道焊情况下两侧同时焊接、热套、预热等工艺以及三层四道焊情况下焊接顺序对焊接残余应力的影响。研究结果表明 ,磁轭圈与辐板焊接后在焊缝及其周围区域产生较大的三向残余拉应力 ;两侧同时焊接可大大降低径向残余应力 ;热套可降低三向残余拉应力 ,热套后直接焊与热套后先冷却后焊相比效果更佳 ;预热可以降低周向残余拉应力 ;多道焊时径向残余应力主要取决于最后一层 ,尤其是最后一道焊缝 ;两侧的最后一道焊缝同时焊接可显著降低径向残余应力 ,而前面的焊道同时焊接与否并不重要。研究结果为优化生产工艺 ,降低残余应力提供了理论依据更多还原

【Abstract】 Using axisymmetric finite elements model ,this study aims to investigate the distributions of the welding residual stresses in a large scale electromotor rotor and the effects of welding procedures, such as welding simultaneously at both sides; shrinkage fitting, preheating ,welding sequence for multipass welds ,etc. The results indicate that high tension stresses in three directions were found in weld bead and its surrounding area; welding simultaneously at both sides can reduce the radial residual stress; heat fitting can reduce the residual stresses in three directions; preheating can reduce the tangential residual stress; the radial residual stress in multipass welds was determined mainly by the last layer, especially the last bead; welding the last beads, of both sides simultaneously can reduce the radial residual stress ,while its not important whether the foregoing beads are welded simultaneously. These results are attractive for the knowledge and the control of the welding residual stresses in the large electromotor rotor.更多还原