焊接速度对核压力容器焊接残余应力的影响

摘要

采用ANSYS有限元分析法,并利用热-结构耦合及生死单元技术,模拟不同焊接速度对核压力容器上马鞍形焊缝焊后残余应力的影响.通过分析焊后温度场和应力场,发现焊缝中心的残余应力最大,随着距焊缝中心距离的增加,应力逐渐变小.其中焊接速度为450 mm/min和400 mm/min时焊后等效应力变化趋势基本吻合,而420 mm/min时焊后的应力值略高于其他两种.%Based on the ANSYS finite element analysis,technology of Hot-Structure coupling and death cell is applied to simulate the influence of different welding speed on the residual stress in the saddle-shaped weld on nuclear pressure vessel.Through analysis of the postweld stress field and temperature field,it is found that residual stress is maximum in the weld center,and the residual stress reduces when the distance from the weld center increases.Wherein,when welding speed is 450 mm/min and 400 mm/min respectively,the postweld equivalent stress variation trends basically coincide,and when welding speed is 420 mm/min,the postweld stress are slightly higher than the other two.