流动沙丘地区油气集输用柔性复合管安全评价方法

Safety evaluation method for flexible composite gathering and transmission pipelines of oil and gas in shifting dune areas

流动沙丘地区敷设柔性复合管具有易悬空、易移位的特点,为了保障油气管道安全、平稳运行,需对管道安全性进行全面评价。选取聚酯纤维柔性增强复合管为例,对流动沙丘致悬空以及侧向挤压作用下柔性复合管的极限承载能力进行了分析。基于轴向拉伸试验结果,明确了柔性复合管的失效过程及其在屈服、强化、径缩等不同状态下的特征应变值;结合有限元分析法,提出了悬空管道极限埋沙坡度、流沙侧向挤压管道极限滑移距离的失效评价依据,并建立了流动沙区地区柔性复合管评价方法,可为沙漠地区油气管道安全输送提供技术保障。

As the flexible composite pipelines in the shifting dune areas are easy to be suspended and displaced,it is necessary to perform a comprehensive evaluation on the safety of oil and gas pipelines to ensure their safe and stable operation.Thus,with a polyester fiber flexible reinforced composite pipeline as the example,analysis was conducted for the ultimate bearing capacity of the flexible composite pipelines under the action of suspension and lateral compression caused by the shifting sand dunes.In addition,based on the axial tensile test results,the failure process of flexible composite pipelines and the characteristic strain values under the different states of yield,reinforcement and shrinkage were identified.Combined with the finite element analysis method,the failure evaluation basis of the“ultimate slope”of suspended pipeline in the sand and the“limited displacement”of pipelines under the lateral compression of quicksand were proposed.Further,the evaluation method for flexible composite pipelines in the shifting sand areas was established,which could provide technical support for the safe operation of oil and gas pipelines in the desert areas.