摘要
水力压裂是目前改善低渗透油藏的主要开发手段,由于压裂液成分复杂,对套管产生严重的局部腐蚀破坏,极大地限制了压裂施工的安全运行。以油田常用套管钢为研究对象,借助电化学工作站,研究套管钢在压裂液中的电化学腐蚀行为,分析不同套管钢材质、压裂液交联比、浓度、KCl含量以及温度等参数对其腐蚀行为的影响规律。结果表明:与N80和J55钢相比,P110钢在压裂液中具有最稳定的钝化特征,点蚀电位最高且钝化电流密度最低,成分中高含量的Cr和Mo及膜层中低的缺陷浓度提高了其钝化稳定性。随压裂液中KCl浓度增加,P110钢钝化稳定性下降;压裂液交联比对其腐蚀行为无影响;点蚀电位敏感于压裂液浓度变化,浓度增加钝化稳定性增加。温度升高,压裂液黏度降低,Cl-迁移作用增加,P110钢点蚀电位降低。
The hydraulic fracturing technology is the main measure to explore the low permeability reservoir. The complex composition of fracturing fluid can lead to the localized corrosion of casing steel and limit the application of hydraulic fracturing technology. The corrosion behavior of P110 casing steel in the hydraulic fracturing fluid was investigated by electrochemical method. The effects of casing steel materials,crosslinking ratio,the concentration,the KCl content and temperature of the fracturing fluid on corrosion behavior of P110 casing steel were studied in detail. The results show that P110 steel exhibits the stable passivation behavior including the highest pitting potential and lowest passivation current density. The high content of Cr and Mo existing in the passive film,and the lowest defect concentration of the film attribute to the stable passivation of P110.The stable passivation of P110 decreases with the increase of KCl concentration. The corsslinking ratio shows little influence on the passivation behavior. The pitting potentials are sensitive to the concentration of fracturing fluid. The low viscocity arising from the high temperature leads to the low pitting potential for the enhancement of Cl-migratation.
出处
《兵器材料科学与工程》
CAS
CSCD
北大核心
2015年第1期29-32,共4页
Ordnance Material Science and Engineering
基金
国家科技支撑计划资助项目(2012BAH28F03)
国家火炬计划(2013GH530190)
黑龙江省自然科学基金项目(QC2013C056)
黑龙江省教育厅科学技术研究项目(12541079)
关键词
套管钢
水力喷砂
压裂
电化学腐蚀
casing steel
hydraulic sandblasting
fracturing
electrochemical corrosion
