瓦庄油田套管腐蚀规律及影响因素研究  

Research on the Casing Corrosion Law and Influence Factor in Wazhuang Oilfield

作　　者：高斐[1] 楼一珊[1] 吴琼[2] 唐礼骅[3] 陈望超 柴妮娜[1] 

机构地区：[1]长江大学石油工程学院 [2]中石化河南油田分公司勘探开发研究院 [3]中石化江苏油田分公司石油工程技术研究院 [4]中石油大庆钻探工程公司修井作业公司

出　　处：《石油机械》2014年第3期61-66,共6页China Petroleum Machinery

基　　金：国家自然科学基金项目"腐蚀-冲蚀耦合作用下套管柱可靠性研究"(51274047)

摘　　要：针对瓦庄油田油井泵吸入口处套管腐蚀行为,研制了一种井下动态腐蚀模拟试验装置。利用该装置进行了不同CO2分压、温度和日产液量等因素控制下套管挂片腐蚀速率的测定,并用SEM、EDS和XRD等方法分析了腐蚀产物膜的微观形貌及化学成分质量分数,在此基础上对套管腐蚀机理进行研究。研究结果表明,瓦庄油田套漏的主要原因是溶解在高矿化度地层水中的CO2腐蚀,并且腐蚀速率随着CO2分压、温度和日产液量的增加而增大,腐蚀形态由全面腐蚀向局部腐蚀转变,腐蚀产物主要是FeCO3;油田无法通过控制油井的温度和CO2分压来预防或减缓套管的腐蚀,所以流体流速是造成泵吸入口处套管腐蚀穿孔的主控因素。建议延长筛管长度或优选筛管孔眼直径来改变流体的流场,以减缓腐蚀。In light of casing corrosion behavior at the suction inlet of oil well pumps in Wazhuang Oilfield, a type of downhole dynamic corrosion simulalion test device was developed. The device was used to study tile corrosion rate of casing coupon under the control of different CO2 partial pressure, temperature and daily fluid production. The methods of SEM, EDS and XRI） were used to analyze the mic,＇oscopic morphology and chemical composition mass fi-action of corrosion scale. On the basis of this, the casing corrosion mechanism was studied. The research findings show that the main reason tbr casing leakage in Wazhuang Oilfield is CO2 corrosion dissolved in highly mineralized formation brines. The corrosion rate increases with the increase of CO2 partial pressure, temperature and daily Iluid production. The corrosion morphology changes from overall corrosion to local cotxosion. The main corrosiml is FeCO3;. The Oilfield cannot prevent or reduce easing corrosion by controlling oil well temperature and CO2 partial pressure. Therelbre, fluid velocity is the main controlling factor for corrosion perforation at pump suction inlet. It is suggested that screen pipe length is increased or screen porl diameter is optimized to change fluid＇ s flow field in or- der to slow down corrosion.

关 键 词：套管腐蚀 CO2分压 温度 流体流速 腐蚀速率 FeCO3 试验装置 

分 类 号：TE985[石油与天然气工程—石油机械设备]