非金属输油管道法兰失效机理研究

Study on Failure Mechanism of Non-Metallic Oil Pipeline Flange

玻璃钢法兰具有耐腐蚀、易成型等优点,但玻璃纤维构件存在各向异性、局部不连续等问题。研究由某油田污水外输管线的玻璃钢法兰发现了开裂、渗漏等问题出发,采用试验研究和数值分析相结合的方法,以现场玻璃钢法兰接头为研究对象,考虑实际运行工况中的载荷,对法兰基材进行力学性能试验,获得了力学特性和损伤条件。构建了包含管道-垫片-法兰的有限元模型,基于非线性Hashin失效准则和Tserpes突降型刚度退化模型对各个工况下的法兰损伤情况进行了分析。

FRP flange has the advantages of corrosion resistance and easy forming,but glass fiber components have problems such as anisotropy and local discontinuity.Starting from the discovery of cracking and leakage in the FRP flange of an oilfield sewage export pipeline,the method of combining experimental research and numerical analysis was adopted,and the on-site FRP flange joint was taken as the research object,considering the load in the actual operating conditions,and the mechanical properties of the flange substrate were tested,and the mechanical properties and damage conditions were obtained.A finite element model including pipe-gasket-flange was constructed,and the flange damage under various working conditions was analyzed based on the nonlinear Hashin failure criterion and the Tserpes sudden drop stiffness degradation model.