海底油气管道焊接接头的安全评定

Safe assessment for welded joint of offshore pipeline

采用欧共体提出的结构完整性评定方法SINTAP(StructuralIntegrityAssessmentProcedure) ,针对API5LX6 5管线钢焊接接头焊趾处的表面裂纹和埋藏裂纹进行安全评定。评定是在给定裂纹尺寸和载荷条件下 ,应用有限元分析 ,根据CTOD(裂纹尖端张开位移 )试验结果进行的。同时根据母材和全焊缝拉伸试验结果 ,建立了X6 5管线钢焊接接头的一级、三级评定曲线。评定结果表明 ,不论是采用一级或是三级评定 ,各评定点均在评定曲线定义的范围内 ,说明该结构是安全的。将SINTAP安全评定方法应用于管道结构 。

Structure integrity assessment procedure (SINTAP) sponsored by the European commission was applied to assessment for welded joints of the API 5L X65 pipeline steel with embedded flaw and surface flaw at the weld toe. Given crack size and load, the assessment was carried out according to the crack tip opening displacement test result and using finite element analysis. The failure lines of level 1 and 3 of the weld were derived from the tensile test results. The assessment showed that all assessment points are located within the failure lines of analysis level 1 and 3. Therefore, welded joint of the pipeline is safe. This study laid the foundation of application of SINTAP to pipeline structure assessment.