焊接余高对锥柱耐压结构典型焊接接头残余应力数值的计算影响

The influence of welding reinforcement on numerical calculation of residual stresses of typical welded joints of cone-cylinder pressure structure

锥柱耐压结构属于大型焊接结构,在其焊接部位存在焊接残余应力。焊接完成后,焊缝区域会留有一定的焊接余高,焊接余高对残余应力数值分析结果有着不可忽略的影响,因此有必要针对焊接余高对焊接残余应力的影响进行相关研究。选取高强度钢锥柱耐压结构典型焊接接头试件为研究对象,利用有限元软件ANSYS的APDL语言编写焊接模拟程序,建立考虑焊接余高的有限元模型和不考虑焊接余高的有限元模型,通过比较两种模型计算结果,研究焊接余高对焊接残余应力的影响,并且得到初始焊接残余应力的分布规律;采用X射线无损检测法测量焊缝区表面的残余应力。结果表明:不考虑焊接余高时,数值分析所得应力分布与考虑焊接余高时应力分布存在很大差异,焊接余高对焊接残余应力分布的影响不可忽略。试验的测量结果符合理论和统计结果,与考虑焊接余高时的数值模拟所得结论基本一致。焊接余高的影响对研究焊接残余应力有很重要的意义,并且对后续考虑残余应力影响的疲劳强度计算有着重要的参考价值。

The cone-cylinder pressure structure belongs to the large welding structures,and there are welding residual stresses in its welding parts. After welding,the weld region will have a certain welding reinforcement,and the numerical analysis of residual stress is affected by welding reinforcement,so it is necessary to carry out research on the effect of welding reinforcement to welding residual stresses. Typical welded joints of cone-cylinder pressure structure of high strength steel is selected as the research object,and APDL language of finite element software ANSYS is used to improve a welding simulation program. Finite element model with welding reinforcement and finite element model without welding reinforcement is built. By comparing the calculation results of the two models,the influence of welding reinforcement on welding residual stresses and the initial welding residual stress distribution is studied. Then,X-ray nondestructive detection method is used to test the residual stresses on the surface of the weld zone. The numerical results show that the distribution of the stress with welding reinforcement is different from the distribution of the stress without welding reinforcement,and the effect of welding reinforcement on distribution of welding residual stress can not be ignored. The test results are consistent with simulative results of the finite element model with welding reinforcement. The influence of welding reinforcement is very important to the study of welding residual stresses,and it will have an important reference value to calculation of fatigue strength considering welding residual stresses.