轴向拘束条件下X70管线钢残余应力释放超声法试验研究  

Study on Ultrasonic Monitoring of Residual Stress of X70 Pipeline Steel under Axial Constraint Condition

作　　者：路浩 苗红钦 武刚 李丽锋 罗金恒 LU Hao;MIAO Hongqin;WU Gang;LI Lifeng;LUO Jinheng(School of Materials Science and Engineering,Xi′an Shiyou University,Xi′an 710065,China;CNPC Engineering Materials Research Institute Co.,Ltd.,State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials,Xi′an 710077,China)

机构地区：[1]西安石油大学材料科学与工程学院,西安710065 [2]中国石油集团工程材料研究院有限公司石油管材及装备材料服役行为与结构安全国家重点实验室,西安710077

出　　处：《焊管》2025年第2期24-30,共7页Welded Pipe and Tube

基　　金：国家管网西部管线公司资助项目“应力监测与残余应力测试”(项目编号0105/290020057)。

摘　　要：管线钢制管工艺过程塑性应变条件多、残余应力残留分布状态复杂、服役环境特殊,为了更好地研究高纲级管线轴向拘束条件下长输管线的残余应力释放规律,针对国内外水压试验标准的差异,同时进一步研究高钢级管线钢管出厂后多次水压试验、地质位移等条件下的残余应力释放规律,通过水压试验平台开展X70高纲级管体水压试验应力检测,分析轴向拘束条件下多次水压试验后管线的残余应力释放规律。采用超声法进行检测,对管体水压试验前、后的残余应力进行跟踪检测,同时采用盲孔法对管线试验切割段的残余应力进行比对验证,得出X70钢管线在不同应变组合下的残余应力释放规律。结果表明,管材残余应力释放的临界条件是材料出现了塑性变形,而在弹性应变条件下管体残余应力不会随应变施加次数的增加发生释放;X70钢级管体轴向强拘束条件下,第一次塑性变形条件下残余应力无释放,第二次塑性变形后,其管体残余应力才发生明显释放。研究结果可为油气管线评估提供一种有效的辅助技术方法。The manufacturing process of pipeline steel pipes involves multiple conditions of plastic strain and a complex distribution of residual stress.In order to better study the residual stress release law of long distance pipeline under axial constraint of high grade pipe line,considering the differences in hydraulic test standards at home and abroad.At the same time,the residual stress release law of high steel grade pipeline steel pipe under the conditions of multiple hydraulic tests and geological displacement after leaving the factory is further studied.The hydraulic test stress detection of X70 high grade pipeline is carried out through the hydraulic test platform,and the residual stress release law of pipeline after multiple hydraulic tests under axial constraint is analyzed.Residual stress before and after the pipeline hydraulic test was tracked by ultrasonic method,and the residual stress in the pipeline test cutting section was compared and verified by blind hole method,and the residual stress release rule of X70 pipeline under different strain combinations was obtained.Results show that the critical condition of residual stress release is the plastic deformation of the material,and the residual stress of the pipe body will not release with the increase of strain application times under the condition of elastic strain.Under strong axial constraint,the residual stress of X70 steel tube body does not release under the condition of the first plastic deformation,but after the second plastic deformation,the residual stress of X70 steel tube body is released obviously.The research results can provide an effective auxiliary technical method for the evaluation of oil and gas pipelines.

关 键 词：油气管道 残余应力 超声法 应力释放 水压试验 

分 类 号：TE832[石油与天然气工程—油气储运工程] TG115.285[金属学及工艺—物理冶金]