焊接顺序对Q370qE桥梁钢焊接残余应力的影响

    Influence of Welding Sequence on Residual Stress of Q370qE Steel

    • 摘要: 利用数值模拟和试验的方法,采用考虑材料性能、双椭球体积热源的顺序耦合热力有限元模型研究了焊接顺序对Q370qE桥梁钢十字接头残余应力的影响。通过对比数值模拟和小孔法实验测得的焊接残余应力,验证了有限元模型。针对实际焊接时所选择的焊道焊接方向,对十字焊接在不同焊接顺序下的残余应力进行模拟。结果表明,焊接顺序显著影响十字接头残余应力的大小和分布,焊道焊接方向对十字接头残余应力大小和分布影响较小;最后一道焊道对峰值应力的位置起着关键作用,峰值应力出现在最后一道焊道根部及其相邻焊道根部位置;与其它焊接顺序相比,对角焊接可使峰值拉应力降低15%左右,最终峰值残余拉应力仅342 MPa。

       

      Abstract: The influence of welding sequence on the residual stress of Q370qE bridge steel cross joint was studied by means of numerical simulation and experiment, using the double ellipsoid volume heat source coupled with thermal-mechanical finite element model considering material properties. Compared with the welding residual stress by numerical simulation and hole drilling method, the accuracy of finite element model was verified. According to the welding bead direction during actual welding, the residual stress of cross welding under different welding sequence was simulated. The results show that the welding sequence significantly affects the magnitude and distribution of residual stress of cross joint,while the welding direction of weld bead has little influence on the magnitude and distribution of residual stress of cross joint.The last pass plays a key role in the location of the peak stress, which appears at the root of the last pass and root of the adjacent pass. Compared with other simulated welding sequences, diagonal welding can reduce the peak tensile stress by about 15%, and the peak tensile residual stress is only 342 MPa.

       

    /

    返回文章
    返回