深层气井生产管柱完整性检测技术总结及评价

Summary and Evaluation of Integrity Detection Technology for Production String in Deep Gas Well

生产管柱完整性失效是深层气井安全稳产所面临的挑战之一,开展完整性检测对于评估和控制相关风险具有重要意义。总结了现有完整性检测技术的作用机理和特点,在归类分析的基础上介绍了典型技术装备和方法。结合案例井分析了深层气井生产管柱完整性检测的技术需求,提出了技术思路和研究建议。分析表明:井下物理场特征是检测生产管柱完整性的主要依据,包括声波、压力、温度、流场和电磁场等,不同检测方法在作业形式和检测能力上具有差异性,主要表现为是否能检测微小泄漏、液面下泄漏和多点泄漏。深层气井温压环境苛刻、环空气液共存、泄漏点及途径多样且多重环空带压,应采用地面诊断定性判别和井下检测定量评价的方式开展完整性评价,重点井可预置分布式光纤实时监测。同时,应提高检测设备耐温耐压性能,提高作业效率和准确性,并在此基础上开展风险预警和管理控制研究,形成地面诊断-井下检测-风险预警-管理控制为一体的技术体系。该研究成果可为深层气井的长期安全稳产提供技术支撑和保障。

Failure of production string integrity is one of the challenges for the safe and stable production of deep gas well.It is of great significance to conduct integrity detection for the evaluation and control of related risk.So,the mechanism and characteristics of available detection technologies are systematically summarized.The typical technical equipment and methods are introduced on the basis of classification and analysis.Combined with case well,the technical requirements are analyzed for the integrity detection of production string in deep gas wells,and the technical ideas and research suggestions are proposed.The analysis indicates that the downhole physical field characteristics are major basis for production string integrity detection,including sound wave,pressure,temperature,flow field and electromagnetic fields,etc.Related detection methods vary in terms of operation and detection capacity,such as detection for small leakage,leakage below liquid level and multiple leakage.Deep gas well has harsh downhole temperature and pressure environment and gas and liquid both exist in the tubing-casing annulus.The number of leakage point and gas migration pathway are various,with multiple annular high pressure.Ground qualitative diagnosis with downhole quantitative evaluation should be adopted to conduct integrity evaluation.For the well of great significance,distributed optical fiber should be deployed for real-time monitoring.Meanwhile,the temperature&pressure resistant properties of equipment should be improved.The work efficiency and accuracy should also be promoted.On the above basis,risk warning and control should also be conducted to build an integrated technical system featuring ground diagnosis,downhole detection and risk warning&control.This research can provide technical support and guarantee for the long-term safe production of deep gas wells.