Φ73.02 mm×5.51 mm P110油管腐蚀原因分析

Investigation of Causes for Corrosion of Φ73.02 mm×5.51 mm P110 Tubing

摘要: 采用现场数据调研、宏观分析、金相分析、扫描电镜分析和 XRD 分析等方法，对某油田Φ73.02mm×5.51 mm P110 油管腐蚀原因进行分析。分析认为：油管腐蚀的主要原因是该井高含量的 CO₂、Cl^-、地层水、返排酸化压裂液共存造成的腐蚀，腐蚀程度与气液交界面的位置及井段温度有关。推荐使用耐 CO₂ 腐蚀的油套管产品。

Abstract: Analyzed in the paper are the causes for corrosion of the Φ73.02 mm×5.51 mm P110 tubing as used in a certain oilfield by means of site-data investigation，macrostructure analysis，metallographic structure analysis， SEM and XRD，etc. The analysis result shows that the primary cause for the tubing corrosion is the co-existence of high contents of carbon dioxide and Cl^-，stratum water and acid fracturing outlet liquid in the well. And the severity of the corrosion is related to the position of the gas-liquid interface and the well section temperature. It is recommended to adopt the anti-CO₂ corrosion tubing and casing.