基于双向强度理论计算钛容器的焊接残余应力

Welding residual stress of titanium vessel calculated by biaxial strength theory

关键词:  双向强度理论  钛制压力容器  焊接残余应力

Key words:  biaxial strength theory  titanium pressure vessel  welding residual stress  formula

摘要:

钛板具有明显的正交各向异性和双向强化效应。根据双向强度理论计算焊接钛制压力容器的残余应力,推导出了计算式并结合试验数据进行了计算分析。结果表明,焊接钛容器纵焊缝处的纵向和环向残余应力都达到钛板屈服强度的50%以上;而环向端焊缝处的纵向和环向残余应力则很不均匀,数值差别较大,某些测点甚至出现负值。对比钛容器的试验焊缝应力与计算焊接应力,可见其最重要的环向应力基本一致,最大差别在15%以内,说明文中的计算方法符合钛容器实际。

Abstract:

Titanium sheet has obvious orthogonal anisotropy and biaxial strengthening effect.Based on the biaxial strength theory, the formula for the welding residual stresses existed in the titanium pressure vessel were derived and the computation and analysises were carried out according to the experimental data.The result indicates that the longitudinal and surrounding residual stresses in longitudinal weld of the welding titanium vessel are greater 50% than the titanium sheet' s yield strength.Moreover, the longitudinal and surrounding residual stresses in surrounding weld are extremely non-uniform.The numerical results show awide difference, and the simulated values of some points are even minus values.Compared the titanium pressure vessel' s experimental welding stresses with the calculated welding stresses, it is found that the most important surrounding stresses are basically consistent, and the greatest difference is less than 15%, which indicates that the computational method conforms with the real situation existed in titanium pressing pressure vessel.