管道内检测腐蚀数据概率分布规律研究及应用  

Research and Application of Probability Distribution Law of Corrosion Detection Data of In-line Inspection in Pipeline

作　　者：闻亚星 贾福生[2] 刘鹏程[2] 王锋 陈金忠[1] 马义来[1] WEN Yaxing;JIA Fusheng;LIU Pengcheng;WANG Feng;CHEN Jinzhong;MA Yilai(China Special Equipment Inspection and Research Institute;Tarim Oilfield Company,CNPC)

机构地区：[1]中国特种设备检测研究院 [2]中国石油天然气股份有限公司塔里木油田分公司

出　　处：《油气田地面工程》2024年第7期70-76,共7页Oil-Gas Field Surface Engineering

摘　　要：腐蚀伴随着管道整个生命周期,管道腐蚀速率评估是管道剩余寿命评估的重要部分,为了提高管道剩余寿命评价的准确性,为制定合理的检测维修周期提供支撑,以某条管道连续两轮漏磁内检测腐蚀数据为基础,并采用最大似然估计法将腐蚀速率与几种常见的概率分布模型进行拟合,通过K-S检验和p-p散点图方法的比较分析,深入研究了该管道径向和轴向腐蚀速率的概率分布规律,发现该管道径向和轴向腐蚀速率的最优分布规律为广义极值分布规律。在此基础上建立了基于概率分布规律的管道剩余寿命评估模型,选取该概率分布模型95%分位数的腐蚀速率作为管道剩余寿命的评估腐蚀速率。分析采用局部腐蚀速率评价方法、最大腐蚀速率评价方法、概率分布腐蚀速率评价方法时5年内需要维修点的数量,结果表明:采用概率分布腐蚀速率评价方法需维修点数量介于局部腐蚀速率评价法和最大腐蚀速率评价法之间,可在一定程度上避免过度维修和维修不及时。Corrosion accompanies the pipeline throughout its life cycle,and the assessment of pipeline corrosion rate is an important part of the remaining life assessment of the pipeline.In order to improve the accuracy of the evaluation of the remaining life of the pipeline,and to provide support for the de-velopment of a reasonable inspection and maintenance cycle,based on two consecutive rounds of mag-netic flux leakage testing corrosion data for a certain pipeline,the maximum likelihood estimation method is used to fit the corrosion rate with several common probability distribution models.By com-paring and analyzing the K-S test and p-p scatter plot methods,the probability distribution law of the radial and axial corrosion rates of the pipeline is deeply studied.It is found that the optimal distribution law of the radial and axial corrosion rates of the pipeline is the generalized extreme value distribution law.On this basis,a pipeline remaining life assessment model based on the probability distribution law is established,and the corrosion rate of the 95%quartile of the probability distribution model is selected as the corrosion rate of the pipeline remaining life assessment.An analysis is conducted on the number of maintenance points required within five years using the local corrosion rate evaluation method,maxi-mum corrosion rate evaluation method,and probability distribution corrosion rate evaluation method.The results show that the number of maintenance points required using the probability distribution cor-rosion rate evaluation method is between the local corrosion rate evaluation method and the maximum corrosion rate evaluation method,which can avoid excessive maintenance and untimely maintenance to a certain extent.

关 键 词：油气管道 内检测 概率分布 腐蚀速率 剩余寿命 

分 类 号：TE988.2[石油与天然气工程—石油机械设备]