腐蚀缺陷管道剩余强度ANSYS有限元模拟可行性研究

Feasibility of finite element analysis on residual strength of pipeline with corrosion defects

以管道实测腐蚀缺陷为依据,用ANSYS有限元法计算含长方形、椭圆形和组合形腐蚀缺陷管道的应力、应变状态,根据第三强度失效准则确定腐蚀管道剩余强度,并结合室内管道承压实验进行了结果验证。结果表明:多个腐蚀缺陷间距对于最大等效应力存在临界值,当双点长方形腐蚀缺陷间距小于60 mm时存在干涉,其最大等效应力高于含单个缺陷管道;ANSYS有限元分析软件建模方法可靠,可以模拟含复杂腐蚀缺陷形状管道的受力状态;模拟结果与室内管道承压实验有较好的吻合度,相同条件下最大偏差小于8.6%。ANSYS有限元分析对于含复杂腐蚀缺陷管道模拟具有准确性和可靠性。

Based on the actual oilfield working condition, the stress and strain state of the pipeline with rectangular, elliptic and combined corrosion defects was calculated by using ANSYS software. According to the third failure criterion, the corrosion residual strength of the pipeline was determined. The experimental verification of finite element model was carried out based on the laboratory pipeline bulge test results. The results show that there exists a critical value between the defect span and maximum equivalent stress, and the double-point rectangular defects with high equivalent stress are dependent with each other when the span is lower than 60 mm. The modeling method of ANSYS is reliable, which can simulate complicated corrosion defects. The experimental and simulated results agree well with each other, and the maximum discrepancy is less than 8.6%. The ANSYS simulation exhibits better accuracy and reliability, and can be used for simulation of complicated corrosion defects.