低碳钢管道焊接残余应力有限元分析

利用ＡＤＩＮＡ非线性分析有限元程序，对低碳钢管道环焊缝接头焊接残余应力进行有限元分析。在热弹塑性分析中考虑了材料热物理和力学性能依赖于温度变化。结果表明：在管道接头内表面焊缝中心及近缝区轴向和环向残余应力均为拉应力，随离开焊缝距离的增加，逐渐过渡为压应力。在管道接头外表面焊缝中心处的轴向残余力为压应力，而环向残余应力为拉应力。计算预测值和实侧值基本一致，表明有限元法能够经济而有效地预测管道环焊缝接头的焊接残余应力。

FINITE ELEMENT ANALYSIS OF WELDING RESIDUAL STRESSES IN A LOW- CARBON STEEL PIPE

The welding residual stresses in a low - carbon steel girth - butt welded pipe are analyzed with a nonlinear finite element code ADINA. The variation of thermal - physical properties and mechanical properties of material with temperature is considered in the thermal - elasto - plastic analysis. The calculated results show that, in the girth welded pipe, the axial and the hoop residual stresses at the weld and weld vicinity on inner surface of pipes are tensile, and they are gradually transferred into compressive stresses with the increase of the departure from the weld. The axial residual stresses at the weld and weld vicinity on outer surface of pipes is compressive while the hoop one is tensile. The calculated results are in agreement with the experimental measurements. It is show that finite element method (FEM) can be capable of predicting the welding residual stresses in girth- butt welded pipes economically and effectively.