雅克拉气田单井集输管道腐蚀及检测

Corrosion of Gathering Pipelines of Single Well in Yakela Gas Field and Testing

雅克拉气田部分单井集输管线腐蚀及穿孔严重,受超声波壁厚检测方法局限性的影响,不能有效地捕获管线腐蚀隐患部位内壁点蚀。通过分析管道输送介质、管道材质、介质运行状态的腐蚀性,优选出针对雅克拉气田单井集输管线的内腐蚀检测方法及检测范围,最终确定雅克拉气田单井管道腐蚀主要介质为Cl-和CO2,其他影响因素为焊缝和流体冲刷等,造成气田单井管道腐蚀减薄的主要原因为CO2电化学腐蚀及冲刷腐蚀。文章通过全面分析,指明各种防腐措施的不足,提出了系统的腐蚀检测方法,为油田类似的腐蚀提供了治理依据。

The gathering pipelines of single well in Yakela Gas Field sufferred from serious corrosion and corrosion failure. The pit corrosion locations could not be accurately located on the internal wall of the pipeline because of limitations of ultrasonic thickness measurement. By the analysis of media of pipeline transmission, pipe metallurgy and corrosivity of media at the operating conditions, a combination of testing methods and testing ranges have been optimally selected for the internal corrosion of single well gathering pipelines in Xinjiang Yakela Gas Field. The main factors affecting the corrosion of the gathering pipelines are chlorine ions, carbon dioxide gas, welds and fluid impingement, etc. The main causes for the corrosion thinning of gathering pipelines of single well in the gas field are the electric - chemical corrosion by carbon dioxide and impingement corrosion. All these provide effective data and basis for the corrosion control in oil and gas fields.