相互影响双腐蚀缺陷管道的剩余强度
Residual strength of pipeline with double corrosion defects interaction
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摘要: 针对现有的腐蚀规范对相互影响双腐蚀缺陷管道剩余强度的评价结果过于保守的问题, 利用非线性有限元分析方法, 分析了含有相互影响双腐蚀缺陷管道的剩余强度, 研究了双腐蚀环向间距、轴向间距对分别具有相同长度、深度的相互影响双腐蚀缺陷管道剩余强度的影响.研究结果表明: 双腐蚀缺陷的环向间距对其相互作用影响不大, 工程上可以忽略; 当双腐蚀缺陷的轴向间距超过一定数值时, 双腐蚀缺陷的相互作用消失; 在一定的轴向间距范围内, 双腐蚀缺陷相互作用随其轴向间距的变化呈对数关系变化.研究结果证实了采用基于塑性失效准则的三维非线性有限元法研究双轴向缺陷腐蚀管道的剩余强度问题是准确、可靠的.Abstract: Evaluation on residual strength of pipeline with double corrosion defects interaction according to the current anti-corrosion regulations is conservative. In this paper, with the non-linear finite element method, the residual strength of pipeline with double corrosion defects interaction is analyzed, and the influences of circumferential pacing and axial spacing of double corrosion defects on the residual strength of pipeline are identified. The results indicate that the circumferential spacing has small and ignorable influence on interaction; when the axial spacing exceeds a certain value, the interaction disappears; within a certain axial spacing, the interaction of double corrosion defects is a log function of axial spacing. The research results prove that the 3D non-linear finite element based on plastic failure can be accurately and reliably used to analyze the residual strength of pipeline with double axial corrosion defects.