双金属复合管线应力分析中当量折算模型的建立与应用*

针对目前高腐蚀性气田的集输系统管线应力分析标准中，未给出双金属复合管线的强度校核方法，依据当量折算理论，将双金属复合管的几何与材料特性转化为等效单层管，通过有限元法验证双层管与等效管模型的计算精度。研究结果表明:利用当量折算理论，可以快速将双金属管外径、壁厚、弹性模量、热膨胀系数、密度等参数等效转化为单层管道相关参数。经实际应用检验，该方法在解决工程问题时具备一定的实用性与准确性；双金属复合管系统当量折算模型具备计算方便和精度高等优点，该模型可用于双金属复合管线结构设计和强度校核。研究结果可为双金属复合管线的强度校核提供1种参考方法。

Establishment and application of equivalent conversion model in stress analysis of bimetal clad pipeline

Aiming at the problem that the strength checking method of bimetal clad pipeline is not given in the stress analysis standards at home and abroad for the bimetal lined pipeline used in the gathering system of high corrosive gas field,according to the equivalent conversion theory,the geometric and material characteristics of bimetal clad pipe were transformed into the equivalent single-layer pipe,and the calculation accuracy of bimetal clad pipeline and equivalent pipe model were verified by the finite element method.The results showed that the parameters such as the outer diameter,wall thickness,elastic modulus,thermal expansion coefficient and density of bimetal clad pipe could be equivalently converted into the single-layer pipe quickly by using the equivalent conversion theory.The practical application indicated that this method had both certain practicability and accuracy in solving the engineering problems.The equivalent conversion model of bimetal clad pipeline system had the advantages of convenient calculation and high precision,and can be used for the structural design and strength check of bimetal clad pipeline.The results can provide a reference method for the strength check of bimetal clad pipelines.