西部某气田井场分离器液相管线法兰腐蚀原因分析  

Corrosion Causes of Liquid Phase Pipeline Flanges for Separators of a Gas Field in the West of China

作　　者：陈庆国 常泽亮[1] 吴超[1] 王帅 丰劲松[1] 岳良武[1] CHEN Qingguo;CHANG Zeiang;WU Chao;WANG Shuai;FENG Jinsong;YUE Liangwu(Tarim Oilfield Company,Petrochina,Xinjiang Korla 841000,China;State Key Laboratory of Performance and Structural Safety for Petroleum Tubular Goods and Equipment Materials,Tubular Goods Research Institute,CNPC,Shaanxi Xi'an 710077,China;College of Chemistry&Environmental Engineering,Yangtze University,Hubei Jingzhou 434023,China)

机构地区：[1]中国石油天然气股份有限公司塔里木油田分公司,新疆库尔勒841000 [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 [3]长江大学化学与环境工程学院,湖北荆州434023

出　　处：《装备环境工程》2024年第2期112-118,共7页Equipment Environmental Engineering

基　　金：国家重点研发计划项目(2017YFC0805804)。

摘　　要：目的 解决西部某气田井场分离器液相出口管线法兰严重腐蚀问题。方法 通过宏观形貌观察、无损检测、化学成分分析、金相组织分析、力学性能测试、腐蚀区域微观形貌观察、腐蚀产物物相分析以及腐蚀电化学实验的方法,分析该法兰发生腐蚀的原因。结果 A105制法兰与316L制密封圈存在较强的电偶腐蚀倾向。结论 电偶腐蚀是导致法兰面严重腐蚀的主要原因,另外,液相管线停用前放空不彻底,法兰底部存在积液,导致气液界面位置叠加发生水线腐蚀。根据法兰腐蚀原因提出了针对性的防腐建议。The work aims to solve the severe corrosion on the liquid phase outlet pipeline flange for a separator of a gas field in the western region.An analysis was conducted to ascertain the causes of the flange corrosion.This analysis involved macroscopic morphology observation,non-destructive testing,chemical composition analysis,metallographic structure analysis,mechanical performance testing,microscopic morphology observation of the corrosion area,phase analysis of corrosion prod-ucts,and corrosion electrochemical experiments.The findings suggested that the A105 flange and the 316L sealing ring materi-als were highly susceptible to galvanic corrosion.In conclusion,galvanic corrosion is the primary contributor to the severe cor-rosion observed on the flange surface.Moreover,inadequate venting of the liquid phase pipeline prior to shutdown also leads to liquid accumulation at the flange base,resulting in compounded waterline corrosion at the gas-liquid interface.Based on the identified causes of flange corrosion,specific anti-corrosion recommendations are proposed.

关 键 词：气田 分离器 法兰 电偶腐蚀 电流密度 电化学 

分 类 号：TG172[金属学及工艺—金属表面处理] TE988.2[金属学及工艺—金属学]