油管钢在模拟超临界CO_2中耐蚀特性的研究  

Corrosion Resistance of Tubing Steels in Simulated Supercritical Carbon Dioxide

作　　者：朱培珂[1] 闫伟[2] 李令东[1] 段保平[1] 沈雪峰 王芹[1] 

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [3]中国石油技术开发公司,北京100009

出　　处：《表面技术》2016年第12期167-173,共7页Surface Technology

基　　金：基金项目:风险探井钻井随钻分析与后期评价研究~~

摘　　要：目的研究普通碳钢P110、3Cr、普通马氏体不锈钢13Cr和超级马氏体不锈钢HP2-13Cr钢在某油井超临界CO_2环境中的耐蚀特性。方法模拟该高温高压高含CO_2且含Cl–油井的腐蚀环境,采用高温高压反应釜对上述四种油管钢进行挂片实验,借助高精度天平、扫描电子显微镜(SEM)、能量色散X射线能谱(EDS)从平均腐蚀速率、清理腐蚀产物后试样的表观特征、腐蚀产物的表面形貌和化学成分及腐蚀机制方面分析其抗均匀腐蚀与抗点蚀特性。结果在CO_2分压达12 MPa,110℃,Cl–质量浓度为16 542 mg/L的典型环境,P110,3Cr油管钢的平均腐蚀速率分别为5.625,2.992 mm/a;13Cr为0.155 mm/a,有点蚀发生,HP2-13Cr则为0.003 mm/a,且为均匀腐蚀,HP2-13Cr能满足模拟腐蚀环境的使用要求。结论在上述超临界CO_2环境,碳钢P110与3Cr在基体表面不存在Cr的富集,耐蚀性差;马氏体不锈钢13Cr和超级马氏体不锈钢HP2-13Cr因基体表面能生成致密的钝化膜,则表现出相对优良的耐蚀性,但两者的合金元素Ni,Mo含量不同,造成了对两者抗均匀腐蚀与抗点蚀性能的显著差异。Objective To research the corrosion resistance of normal carbon steel P110, 3Cr, martensitic stainless steel 13 Cr and super-martensitic stainless steel HP2-13 Cr in simulated supercritical CO_2 environment. Methods The corrosive environment of high temperature/ high pressure/CO_2 enriched and Cl– contained oil well was simulated. The above four kinds of steels were tested by blade-hanging with a high temperature and high pressure reactor. Their characteristics of anti-general corrosion and corrosive pitting were analysed in the aspects of average corrosion rate, surface characteristics of samples after clearing the cor-rosion products, surface morphology, composition of corrosion products and corrosion mechanism using high class electric balance, scanning electron microscopy（SEM） and energy dispersive spectroscopy（EDS）. Results In the environment at 110 and ℃containing 12 MPa partial pressure of CO_2 and 16 542 mg/L Cl–, the average corrosion rate of P110 and 3Cr were 5.625 mm/a and 2.992 mm/a respectively. The corrosion rate of 13 Cr was 0.155 mm/a and pitting corrosion occurred on its surface, the corrosion rate of HP2-13 Cr was 0.003 mm/a and general corrosion occurred. HP2-13 Cr met the using requirement in the corrosive environment. Conclusion In the above supercritical CO_2 environment, the corrosion resistance of carbon steel P110 and 3Cr is low because no tight corrosion films containing rich Cr covered on their metal. The corrosion resistance of martensitic stainless steel 13 Cr and super-martensitic stainless steel HP2-13 Cr are better than the two former due to dense passivation film on the surface. However, the content difference of Ni and Mo contribute to significant difference in their resistance to general corrosion and corrosive pitting.

关 键 词：CO2腐蚀 超临界 油管钢 点蚀 钝化 

分 类 号：TG174.4[金属学及工艺—金属表面处理]