ASME B 31G规范把复杂的腐蚀坑剖面曲线简化成矩形或抛物线投影，是造成ASME B 31G规范预测结果出现保守和不稳定性的重要原因。文章采用非线性有限元方法，综合分析了腐蚀坑剖面面积和腐蚀坑形状系数对腐蚀管道失效压力的影响，提出一种新的以腐蚀坑剖面面积和腐蚀坑形状系数描述腐蚀坑形貌的B31G修正公式，实际算例表明新提出的B31G修正公式的预测结果保守性低，预测误差稳定。%The failure pressure of oil and gas pipeline with different morphology of corrosion pits was anal-ysed by using the nonlinear finite element method. The impact of the cross-section area of corrosion pit on pipeline failure pressure with the axial and circumferential corrosion was researched. The analysis showed that the cross-section area of corrosion pits seriously influenced the failure pressure of pipeline with axial corrosion, however, which was not enough to fully describe the effects of the morphology of corrosion pits on pipeline failure pressure. The research considered the effects of the morphology of corrosion pits by us-ing the cross-section area of corrosion pit and form factor of corrosion pit to descripe on pipeline failure pressure, and proposed a new B31G correction formula. The results show that forecast error and the fluctu-ation range of the error are little using the formula.
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