含内外壁缺陷油气管道的极限压力

Extreme pressure of oil/gas pipeline with internal/external wall defects

管道缺陷是引起管道失效最常见的一种因素,而塑性极限压力是管道结构设计的重要参数,其与材料性能密切相关。对内外壁分别含有缺陷的管道的极限压力进行对比研究,采用有限元模拟的方法,针对管壁上的球面缺陷及沟槽型缺陷进行模拟,并对含缺陷管道的极限压力与完整管道的极限压力进行对比,指出缺陷分布在管道内壁或外壁对于管道的极限压力有着不同的影响。通过管道缺陷参数对极限压力的影响作用,进一步分析了缺陷分布位置不同引起极限压力差别的影响因素,结果表明:分布在内壁或外壁的沟槽型缺陷对管道极限压力有影响,且影响程度主要与缺陷的长度有关。

Pipeline defect is one of the most common factors causing pipeline failure, and the plastic extreme pressure is an important parameter of pipeline structure design which is closely related to material performance. Comparative study is conducted on pipelines with internal or external wall defects. Finite element modeling method is used to simulate the sphere defect and groove defect of pipe wall, and the pipeline with defects is compared with integrated pipeline for extreme pressures, suggesting that the defects on the internal or external wall will have different influences on the extreme pressure. Considering such influences, the impacts of different distribution positions of defects on extreme pressures are analyzed. The result shows that the groove defect distributed on the internal or external wall has impact on the pipeline extreme pressure to the extent related to the length of defect.