管道螺旋焊缝缺陷的初级失效评估

阐述了焊缝缺陷的评估原理和分级方法,参考英国标准BS 7910的1A级断裂评估准则,提出了螺旋焊缝缺陷失效的初级评价方法,并针对庆铁老线林源至新庙段管道的超声检测数据进行了应用性计算.对螺旋焊缝缺陷的断裂失效和塑性破坏失效的评估结果表明,部分缺陷在内压大于4.5 MPa下不安全.研究认为,在实现较高级评估之前,初级失效评价结果可以为螺旋焊缝的检测、完整性评价和缺陷修复等完整性决策提供参考和指导.

Preliminary Failure Evaluation on Spiral Seam Defects of Pipeline

Evaluation principle and grading method on spiral seam defects of pipeline are described.On the basis of Grade 1A of Code BS 7910,preliminary failure evaluation method of spiral seam defects of pipeline is proposed,and applied calculation is conducted on UT data acquired from Lingyuan-Xinmiao pipeline section in Taqing-Tieling Oil Pipeline.Evaluation results about fracture failure and plastic collapse failure of spiral seam defects of pipeline display that some flaws in pipes detected are not safe when an internal pressure is greater than 4.5 MPa.It is concluded that the preliminary failure evaluation provides a useful outcome for reference in making decision of inspection,integrity assessment and repair of spiral seam pipeline,and hence is a step of fundamental importance and practical significance before more accurate data become available for higher grade assessment.