低铬油套管钢材在不同工况下的腐蚀规律研究  

Corrosion Characteristics of Low Cr-containing Tubing and Casing Steel under Various Service Conditions

作　　者：张晓诚 林海 廖前华 李文博 董平华 ZHANG Xiao-cheng;LIN Hai;LIAO Qian-hua;LI Wen-bo;DONG Ping-hua(State Key Laboratory of Offshore Oil Exploitation,CNOOC Limited,Tianjin Branch,Tianjin 300459,China)

机构地区：[1]中海石油(中国)有限公司天津分公司海洋石油高效开发国家重点实验室,天津300459

出　　处：《装备环境工程》2022年第11期95-101,共7页Equipment Environmental Engineering

基　　金：国家重大专项(2016ZX05058-002)。

摘　　要：目的研究低铬油套管钢材在不同腐蚀环境中的腐蚀特征。方法采用高温高压动态反应釜对1Cr、3Cr这2种常用低铬油套管钢材进行纯CO_(2)、CO_(2)和低浓度H_(2)S共存条件下的腐蚀试验。结果温度在40~80℃条件下,各种钢材的腐蚀速率随着温度的升高而变大。加入低浓度H_(2)S后,可以抑制CO_(2)腐蚀,且随着温度升高,抑制性逐渐减弱。分析认为,在单独CO_(2)环境以及CO_(2)和低浓度H_(2)S共存的环境中,1Cr、3Cr钢表面出现铬富集现象,形成的Cr(OH)_(3)膜保护基底。同时,在CO_(2)和低浓度H_(2)S共存的环境中,1Cr、3Cr钢表面形成致密的FeS产物膜有助于保护基底,抵抗Cl^(-)侵蚀。结论低Cr钢表面因铬的富集形成钝化膜,能有效抑制油套管的腐蚀速率,以上研究成果对CO_(2)和低浓度H_(2)S环境中的腐蚀理论以及油田油套管材料合理选择均有一定指导意义。The paper aims to study the corrosion characteristics of low chromium tubing and casing steel in different corrosion environments.High temperature and high pressure dynamic reactor is used to conduct corrosion experiments on 1Cr and 3Cr steels in pure CO_(2),CO_(2) and low concentration H_(2)S environments.The results show that the corrosion rate of various steels increases with the temperature at 40℃-80℃.The addition of low concentration H_(2)S can inhibit CO_(2) corrosion,and the inhibition gradually weakens as the temperature rises.According to the analysis,in CO_(2),CO_(2) and low concentration H_(2)S environments,pitting corrosion of N80 steel will occur.Chromium enrichment occurs on the surface of 1Cr and 3Cr steels,and the formed Cr(OH)_(3) protects the substrate.At the same time,in CO_(2) and low concentration H_(2)S environments,the amount of FeS product is formed on the surface of 1Cr and 3Cr steels.The dense FeS product helps protect the substrate and resist Clerosion.Passive film is formed on the surface of low Cr^(-) steel due to chromium enrichment,which can effectively inhibit the corrosion rate of steel.The research results have enriched the corrosion theory in CO_(2) and low concentration H_(2)S environments and the reasonable selection of oilfield tubing and casing materials.

关 键 词：CO_(2)腐蚀 H_(2)S腐蚀 油套管钢 腐蚀形貌 腐蚀机理 腐蚀速率 

分 类 号：TG172[金属学及工艺—金属表面处理]