HFW焊管残余应力分析

Residual Stress Analysis of HFW Pipe

采用小孔检测法研究了规格Φ406.4 mm×12.5 mm、钢级L415MB的HFW焊管残余应力的分布情况。试验结果表明,HFW焊管整体残余应力值较小,并且轴向残余应力大于环向残余应力,轴向和环向最大值分别约为母材屈服强度的38%和29%;HFW电阻焊焊缝及其附近区域的残余应力值低于管体区域,轴向和环向残余应力的变化范围分别约为母材屈服强度的24.5%～33.6%和16.4%～21.5%;HFW电阻焊管轴向和环向残余应力的差异呈周期性变化,距离焊缝15°附近时差异最小。试验结果对于HFW电阻焊管在长输管线的应用提供理论支持。

The distribution of residual stress on L415MB HFW pipe with the dimension ofΦ406.4 mm×12.5 mm was studied by the hole-drilling technique. The results indicated that overall residual stress value was rather small. The value of axial stress was larger than that of the circumferential stress. The highest values of axial and circumferential stress were respectively about 38% and 28% of base metal yield strength. The residual stress value in the vicinity of weld seam was smaller than the value in the pipe body. The highest axial and circumferential stress values changed in the range of 24.5%~33.6% and 16.4%~21.5%. The difference of axial and circumferential residual stress changed periodically, the minimum value appeared every 15＆#176; away from the weld seam. The test results provided theoretical support for application of HFW pipe in long-distance pipeline.