海底管线服役条件有限元应力分析

摘要

In this paper, the service stress condition of φ559 mm×28 mm SMYS 450 marine pipe with concrete weight coating under transmission pressure 25 MPa at 1 500 m subsea was analyzed by the Finite Element Methods(FEM). The result showed that the maximum displacement was 0.046 4 ×10-3 m within the c onstraint of the weight coating, and the displacement was 0.104×10-3 m without weight coating constraint. The maximum stress of both the 1st principal stress and Von mises equivalent stress were 128 MPa and 216 MPa respectively, which located near the interface between the pipe body and the counterweight layer, about 2 mm to the outside surface of pipe body (28 mm wall thickness). It also indicated that the operation was safety, and using the Von mises equivalent stress criterion as pipeline acceptance limit is workable.%采用有限元方法模拟分析了带配重层海洋管准559 mm×28 mm SMYS 450在海底1500 m和输送压力为25 MPa 条件下服役时的应力状态，结果显示，在受配重层约束下的最大位移为0.0464×10-3 m，无配重约束位移为0.104×10-3 m；第一主应力和Von mises 等效应力的最大值都分布在管体材料和配重层之间的界面处附近，距离管体外表面约2 mm（壁厚28 mm），最大值分别为128 MPa和216 MPa。模拟结果表明，管线运行是安全的，也说明了采用Von mises 等效应力准则作为管道问题验收极限是可行的。