近年来众多油气输送管道及沿线站场设施环焊缝失效事故表明，焊缝缺陷是引发管道失效的一个重要因素。通过分析8起典型的环焊缝失效案例，发现高钢级(X 70、X 80)管道发生失效的主要模式为断裂，而焊缝未熔合缺陷是高钢级管道环焊缝发生失效的主要原因。输送管道环焊缝开挖检测结果表明，环焊缝主要存在焊接缺陷和外观几何缺陷两种，多为叠加出现。通过现场调研发现，站场设施环焊缝存在对接材质不同、壁厚不等及对接结构多样等特点，其失效原因也更复杂。国内外环焊缝修复标准调研分析表明，国内尚无专门针对高钢级管道修复的行业标准，现有的关于环焊缝缺陷修复的企业标准之间存在较大矛盾和差异。最后，针对油气输送管道和站场设施环焊缝问题提出了应开展环焊缝缺陷修复技术可靠性验证试验、失效机理和失效控制措施等方面的研究，为解决工程现场问题奠定理论基础。

In recent years, many pipelines and transmission station facilities failure accidents show that weld defect is an important factor in pipeline failure. The paper analyzes 8 girth weld failure cases and finds that fracture is the main mode of high steel pipeline (X70, X80) failure, and incomplete fusion defects is the main reason for high steel pipeline girth weld failure. At the same time, indicated by the excavation results, there are two kinds of defects of pipeline girth weld, welding defects and appearance defects, mostly superposed. Since girth weld of transmission station facilities have different material, different wall thickness and complex joint characteristics, the cause of failure is relatively complex. Investigation and analysis of girth weld rehabilitation standards at home and abroad shows that there are no specifically industrial standards for high pipeline rehabilitation at home, and there are contradictions and differences between the existing enterprise standards for girth weld defects rehabilitation. Finally, for pipeline and station facilities girth weld problems, girth weld defects rehabilitation technology, reliability verification test and failure mechanism and failure control measures shall be carried out to provide a theoretical foundation for solving the engineering problems.