The work aims to obtain the magnitude and distribution mode of welding residual stress of X80 high-grade pipe-line girth weld.Firstly,the blind hole method was used to test the welding residual stress of the girth weld of a X80 high steel grade pipeline.Then,the test results were compared with the relevant literature test data of the welding residual stress of the X80 pipeline and the content stipulated in the national standard"Safety Assessment of Pressure Vessels with Defects in Use"GB/T 19624-2019.Finally,according to the test data,the functional relationship between the welding residual stress of the girth weld of the X80 high steel grade pipeline and the distance from the weld center was proposed,and the calculation formula of the welding residual stress along the circumferential and axial directions of the girth weld of the X80 pipeline was further ob-tained.The results showed that there was a large residual tensile stress in the circumferential weld of the X80 pipeline along the circumferential area,and the welding residual stress reached the peak in the weld toe area.The circumferential residual stress increased with the distance from the center of the weld,and the tensile stress increased slightly.After reaching the peak value of 567 MPa,it rapidly changed into compressive stress,and then slowly changed into tensile stress and tends to zero.The axial re-sidual stress decreased rapidly from the peak compressive stress of 92 MPa near the wend fusion line to the peak tensile stress of 188 MPa at 16 nm to the fusion line with the increase of the distance from the weld center.According to the test results,the dis-tribution mode of welding residual stress along the circumferential and axial directions of the girth weld of X80 pipeline is pro-posed,which provides a theoretical reference for the safety assessment and repair of X80 pipeline with defects.
关键词
X80管道/焊接残余应力/盲孔法/环焊缝/试验研究
Key words
X80 pipeline/welding residual stress/blind hole method/girth weld/experimental study
维普
万方数据