中俄东线天然气管道弯曲变形识别与评价

管道在外部载荷的作用下会发生局部位移及弯曲变形,当与管体腐蚀、制造或焊缝等缺陷叠加时,在应力集中点将引起管体失效,严重威胁人员安全、造成环境污染及经济损失。基于惯性测绘的内检测技术是一种准确识别管道弯曲变形及检测弯曲应变的有效方法,在对管道全线实施检测的同时以弯曲应变的形式反映管道在外部载荷作用下的弯曲状态。中俄东线天然气管道境内段途经沼泽、高寒冻融等地质不稳定区域,洪水、地震等自然灾害引起土体移动也会对管体施加外部载荷,在外力作用下管体发生弯曲的可能性较大,易因局部应力集中形成高风险点,通过分析管道弯曲应变数据,结合几何/漏磁内检测发现的管体缺陷,可以更加精确地识别定位对管道安全运行构成潜在威胁的高风险点,有针对性地制定监测、修复计划,为中俄东线天然气管道的安全运行提供有效保障。(图7,参21)

Identification and evaluation on bending deformation of China-Russia Eastern Gas Pipeline

Local displacement and bending deformation of pipeline may occur under the action of external load.When superimposed with defects such as pipeline body corrosion,manufacturing or weld defects,the pipeline body will probably fail at the stress concentration point,seriously threatening the safety of personnel and causing environmental pollution and economic losses.In-line inspection technology based on inertial surveying and mapping is an effective method to accurately identify the bending deformation of pipelines and detect bending strain,which reflects the bending state of pipelines under external load in the form of bending strain during detection of the whole pipeline.The pipeline section of China-Russia Eastern Gas Pipeline within China starts from Heihe in the north and terminates at Shanghai in the south,passing through the geologically-unstable areas like marshes,freezing and thawing in alpine regions,where the movement of soil caused by natural disasters such as floods and earthquakes may also exert external load on the pipeline body.The pipeline body is likely to bend under the action of external force,and high-risk points are prone to be generated due to local stress concentration.By analyzing the bending strain data of the pipeline in combination with the pipeline defects found by geometric/leakage flux in-line inspection,the high-risk points that pose potential threats to the safe operation of the pipeline can be identified and located more accurately,and the monitoring and repair plans can be developed accordingly,so as to provide effective means for the safe operation of China-Russia Eastern Gas Pipeline.(7 Figures,21 References)