In order to analyze the influence of corrosion defects on the safety of oil and gas pipeline,an overhead pipeline model of different corrosion depth using the finite element software-ADINA was built in this article,and the research on the value of circumferential stress in the pipe with corrosion-defect under the gravity and internal pressure was carried out.Compared with the analysis results and specification standards the credibility of the model and its parameters were verified,and the results of the finite element were modified based on the numerical regression.It was found that the circumferential stress of the pipe is increased with the increase of the corrosion depth;pipe may be destroyed when the external corrosion depth is more than 40％ of the wall thickness,or the internal corrosion depth is more than 50％ of that;when the corrosion depth is less than 60％ of the thickness,the stress resulted from fimite element analysis,in which stress concentration is taken into account,is larger than the from specification-based approach,zand the deviation is within 15％;when the corrosion depth is more than 60％ of thickness,the stress from the finite element analysis,in which the effect of deformation is taken into account,is smaller than that from the specification-based approach,and the deviation is over 50％.The formula obtained from numerical regression is more accurate for the evaluation of internal corrosion than for external corrosion.%为分析腐蚀缺陷对油气管道安全性的影响,利用有限元软件ADINA建立含不同腐蚀深度的架空管道模型,研究腐蚀管道在重力和内压作用下的应力峰值,通过结果与规范对比验证了模型的可信性,并用数值回归法对有限元结果做了进一步修正.研究发现:管道的环向应力随腐蚀深度的增加而增加;当外腐蚀深度超过壁厚的40％,或内腐蚀深度超过壁厚的50％时,管道有破坏风险;当腐蚀深度小于60％时,有限元模型因考虑应力集中现象,计算结果比规范法偏大,差值率在15％以内,当腐蚀深度大于60％时,有限元模型因考虑破坏变形影响,计算结果比规范法偏小,差值率超过50％;经数值回归法所得公式在内腐蚀评价方面效果优于外腐蚀.
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