耐热钢厚壁管环焊残余应力的有限元分析

Finite element analysis on welding residual stresses of thick wall pipe of heat resistant steel

关键词:  管道  焊接残余应力  有限元法

Key words:  pipe  welding residual stresses  finite element method

摘要:

以热-弹塑性理论为基础,建立了厚壁管环焊残余应力的二维轴对称有限元模型,利用ANSYS有限元分析软件,模拟了耐热钢厚壁管环焊对接的应力分布。结果表明,焊缝内表面及其附近处的轴向应力和环向应力均是拉应力,而外表面是压应力,接头处内表面应力水平高于外表面;径向应力数值远低于环向应力和轴向应力;各方向残余应力的最大值均位于距管道外表层一定距离处,其数值大小接近于材料的屈服点应力。

Abstract:

A two-dimensional axial-symmetric finite-element model of welding residual stresses of thick-wall pipe has been proposed based on the theory of thermal-elastoplasticity.Using ANSYS finite-element program,the welding stresses of heat resistant steel is simulated.The results show that both the hoop stresses and axial stresses are tensile stress in the inner surface zone of welded joint,but the compression stress appears in the outer surface zone.The stress value near the inner surface is higher than the one of the outer surface in the joint,and radial stresses are less than hoop stresses and axial stresses.The maximal value of residual stresses appears in the certain distance beneath exterior surface of the pipe,and the value is close to the yield stress.