API 5L X56管中管横向冲击性能的数值研究

Numerical investigation of transverse anti-impact performance of API 5L X56 pipe-in-pipe

随着海洋石油行业的蓬勃发展,油气田开发不断向深海发展,对海底管道性能的要求也不断提高。管中管具有良好的保温性能而逐渐得到应用;为系统地研究管中管结构的横向抗冲击性能,采用非线性有限元程序建立了数值模型,并与试验数据进行验证。参数化研究发现,一定冲击能量下,聚氨酯泡沫所吸收的能量与管中管的内管和外管所吸收能量的总和相比所占比重较小;随管中管壁厚和钢材等级的提高,管道的局部凹陷程度降低,海底管中管抵抗冲击变形的能力越强;随管中管悬跨长度增加,管中管跨中截面的残余位移逐渐增大,而横截面残余变形和局部凹陷深度逐渐减小,整体弯曲变形所占的比重逐渐增加,局部凹陷所占的比重有所减小。

With vigorous development of offshore oil industry,development of oil and gas fields continues to develop into deep sea,and requirements for performance of submarine pipeline also continuously increase.Pipe-in-pipes are gradually applied due to their good thermal insulation performance.Here,to systematically study lateral anti-impact performance of pipe-in-pipe structure,a numerical model was established using a nonlinear finite element code and verified with test data.Parametric study showed that under a certain impact energy,the energy absorbed by polyurethane foam occupies a smaller proportion than the sum of energy absorbed by inner pipe and outer pipe of pipe-in-pipe does;with increase in pipe wall thickness and steel grade of pipe-in-pipe,the local depression degree of pipeline drops,and the ability of submarine pipe-in-pipe to resist impact deformation is stronger;with increase in suspended span length of pipe-in-pipe,residual displacement of midspan cross-section of pipe-in-pipe gradually increases,while other sections’residual deformation and local depression depth gradually decrease,the proportion of overall bending deformation gradually increases,and the proportion of local depression gradually decreases.