残余应力对钢管-焊接空心球节点疲劳强度的影响分析

Impact analysis of residual stress on fatigue strength of steel pipe-welded hollow spherical joints

以钢管-焊接空心球节点为研究对象,运用有限元分析软件ANSYS,采用相应的物理模型,考虑了钢材物理参数及力学参数随温度变化的非线性性能,采用生死单元技术对焊接过程中加热及冷却温度场的正确模拟,得出焊缝在不同时间段的焊接温度分布,将热单元转化为结构单元,得出焊缝在各时间段的应力分布,说明采用ANSYS软件模拟焊缝的焊接过程是可行的。分析残余应力对构件疲劳强度的影响,提出减小残余应力的措施。

Based on the steel pipe-welded hollow spherical joints as the object of the research,the finite element analysis software ANSYS was used,the corresponding physical model was adopted with considering on the nonlinear properties of the physical parameters and dynamics parameters for the steel changing with temperature,the death and birth elements technology was used to simulate correctly for heating and cooling in the process of welding temperature field,the welding temperature distribution in different periods were concluded,thermal unit was converted to structural unit,the stress distribution of each period was drawn. It is feasible to use the ANSYS software to simulate the welding process of the welding. The effects of residual stress on fatigue strength of components were analyzed,and measures of reducing residual stress were put forward.