含体积型缺陷管线表面应力应变状态的有限元模型分析及试验验证

腐蚀是影响油气管道安全运行的主要因素,确定预测腐蚀管道的剩余强度和其剩余寿命的方法有重要意义。应用ANSYS软件对含内腐蚀缺陷管道的三种模型进行有限元分析,得到采用1/4模型计算更简便、高效;由两种边界条件的模拟结果可知,自由边界条件下缺陷中心处的应变数值较高。管道外壁周向应变峰值分别与缺陷直径呈线性关系,与缺陷深度呈指数关系。并利用电阻应变片测量的值,与相同条件下模拟值的偏差不超过5.3%,结果表明,该建模方法是可靠的。

Analysis and Experimental Verification of Finite Element Model for Stress and Strain State of Pipeline with Volume -scale Defect

Corrosion is the main factor which affects the safe function for the oil and gas pipeline. Establis- hing a method to predict the residual strength and remaining life of corroded pipe has a very important sig- nificance. ANSYS software was applied to analyze the oil and gas pipeline with inside corrosion defect through establishing three different models, and 1/4 model turns out to be more convenient and efficient. A comparative analysis of two boundary conditions exhibits that the numerical values under free boundary condition are higher. Simulated results demonstrate that the value of pipe strain is increased by the linear increasing defect diameter and the exponential increasing defect depth. Strain gauge is applied to measure the experimental values of pipe strain under certain defect diameter and depth. The comparison results be- tween the experimental and simulated values indicate that this modeling method is reliable, and the maxi- mum discrepancy is less than 5.3%.