棘轮效应对海底管道工程设计影响的有限元评估  

Finite element assessment of influence of ratcheting effect on subsea pipeline design

作　　者：黄钰[1] HUANG Yu(Offshore Oil Engineering Co.Ltd.)

机构地区：[1]海洋石油工程股份有限公司

出　　处：《油气储运》2023年第4期447-453,共7页Oil & Gas Storage and Transportation

基　　金：中国海油重大技术研发项目“钢悬链立管设计制造安装”,LSZX-2020-HN-042017D-5007-0605。

摘　　要：棘轮效应广泛存在于服役期启动、关停操作频繁的海底管道中,严重影响其在位状态及结构安全。为此,结合海底管道流动保障要求及管土作用影响分析海底管道棘轮效应的诱发机理,形成海底管道棘轮效应筛选判别方法,并提出海底管道工程设计中针对棘轮效应影响的有限元评估方法。以某单点系泊系统中外输海底管道工程为例,开展管道棘轮效应影响的有限元评估,结果表明:该管道稳定循环下恒定摩擦力与土壤摩擦力的比值为1.91,棘轮效应相对明显;相比于常规热膨胀计算,在工程设计中应额外考虑0.09 m棘轮效应位移的影响。研究成果可为海底管道、膨胀弯及水下管汇的工程设计提供理论支撑,使工程设计结果更符合海底管道真实的服役状态。(图3,参27)Ratcheting effect exists widely in subsea pipelines with frequent operation for startup and shutdown during the service period,and it seriously impacts the in-place statement and structural safety of subsea pipelines.Hence,the triggering mechanism of ratcheting effect on subsea pipelines was analyzed with consideration to the requirements of flow assurance and the impact of pipe-soil interaction.Meanwhile,a screening and identification method of ratcheting effect was developed for the subsea pipelines,and a finite element assessment method of ratcheting effect was proposed during the engineering design of subsea pipelines.As a case study,the finite element assessment on ratcheting effect of pipeline was performed based on an export subsea pipeline in a single-point mooring system.According to the results,the ratio of constant friction to soil friction of a pipeline under constant circulation is 1.91,which indicates a relatively obvious ratcheting effect.So,compared with the conventional calculation on thermal expansion,the impact of another 0.09 m ratcheting displacement should be considered in the engineering design.In general,the research results could provide theoretical support for the engineering design of subsea pipelines,expansion bends and underwater manifolds,so that the design results would be in better agreement with the actual service status of subsea pipelines.(3 Figures,27 References)

关 键 词：海底管道 棘轮效应 循环荷载 热膨胀 总体屈曲 有限元评估 

分 类 号：TE832[石油与天然气工程—油气储运工程]