Finite element analysis of stress of pipe girth welds with pit defects

含凹坑缺陷管道环焊缝应力有限元分析 Finite element analysis of stress of pipe girth welds with pit defects 储玲玉 CHU Lingyu 1 2 first-author 刘觉非 LIU Juefei 2 苏林 SU Lin 2 毛瑞麒 MAO Ruiqi 1 徐杰 XU Jie 1 鲍庆河 BAO Qinghe 3 李鑫 LI Xin 3 中国矿业大学材料与物理学院 中国矿业大学材料与物理学院 School of Materials Science and Physics,China University of Mining and Technology School of Materials Science and Physics,China University of Mining and Technology 中石化长输油气管道检测有限公司 中石化长输油气管道检测有限公司 SINOPEC Oil & Gas Pipeline Inspection Co.,Ltd. SINOPEC Oil & Gas Pipeline Inspection Co.,Ltd. 徐州巴特工程机械股份有限公司 徐州巴特工程机械股份有限公司 Xuzhou BUT Construction Machinery Joint-stock Co.,Ltd. Xuzhou BUT Construction Machinery Joint-stock Co.,Ltd. 基于有限元方法,采用ABAQUS有限元仿真模拟软件,参考实际管道环焊缝的坡口形状和热影响区材料的软化现象,建立了含凹坑缺陷管道环焊缝非线性有限元分析模型,对不同载荷作用下的含凹坑缺陷管道环焊缝进行应力分析,探讨了凹坑尺寸、焊缝余高以及热影响区材料属性等因素对应力分布的影响规律。结果表明:凹坑周边发生明显的应力集中,凹坑深度对管道极限承载力影响显著,随着凹坑深度的增加,腐蚀管道的最大等效应力显著增大,且峰值应力集中在焊缝区;腐蚀管道在极端拉伸载荷作用时,焊缝余高内凹坑缺陷的最大等效应力集中在热影响区;凹坑深度大于余高时,最大等效应力位于焊缝中心的凹坑边缘。 This paper based on the finite element method,using ABAQUS software,referring to the groove shape of the actual pipe girth weld and the softening phenomenon of the heat-affected zone material,a nonlinear finite element analysis model of the pipe girth weld with pit defects is established.The stress of pipe girth welds with pit defects under different loads was analyzed. The influence of pit size,weld reinforce-ment and material properties of heat-affected zone on the stress distribution of circumferential welds of pipelines with pit defects was discussed. The results show that obvious stress concentration occurs around the pit,and the depth of the pit has a significant influence on the ultimate bearing capacity of the pipeline. As the depth of the pit increases,the maximum equivalent stress of the corroded pipeline increases significa-ntly,and the maximum stress is concentrated in the weld zone.When the pipeline is under extreme tensile load, the maximum equivalent stress of the pit defect in the weld reinforcement is concentrated in the heat-affected zone;when the depth of the pit is greater than the reinforcement,the maximum equivalent effect force is located at the edge of the pit in the center of the weld. 管道环焊缝 凹坑缺陷 焊缝余高 有限元分析 安全评估 pipe girth weld pit defects weld reinforcement finite element analysis safety assessment TE973.3 国家自然科学基金资助项目（51301197）;江苏省自然科学基金资助项目（BK20130182）;国家重点研发项目（2018YFB2001204） 2022-03-08 4 51