井下节流技术在南海东部高温气田的应用

Application of Downhole Throttle Technology in High Temperature Gas Fields in Eastern South China Sea

南海东部海域某深水气田属于高温气田,受高温天然气的影响,完井管柱和生产管柱产生轴向变形,导致采油树升高,引起井口管线应力变形,严重影响生产安全。通过减小产量可以降低温度对完井管柱和生产管柱的影响,进而减小采油树升高幅度。降产控制采油树升高会导致产量缺口,且不利于气田协同开发。针对该问题,本文通过神经网络方法找到引起采油树升高的主控因素。在此基础上,本文通过研究天然气自身特性,提出了节流降压降温方案,建立了井筒温度模型,设计并制造了适用于高温气井的井下节流工具。该工具在现场成功实施后,有效降低了井筒温度,减少了采油树升高,保障生产安全的同时提高单井产能17万方/天。通过以上研究,总结并形成了一套可用于不同高温气井、同一高温气井的不同生产时期的井下节流工艺设计方案,保障了高温气井安全生产,同时实现了单井高效生产、气田协同开发,对于高温气田的开发具有很好的指导意义。

A certain deepwater gas field in the eastern South China Sea is a high-lemperiature gas field.Affected by the high temperature natural gas,the completion string and the production string are axially deformed,causing the rise of the Christmas tree and the stress deformation of the wellhead pipeline,which seriously afects production safety.By reducing the output.the influence of temperature om the completion string and production string can be reduced,thereby reducing the rise of the Christmas tree.Decreasing production and controlling the rise of Christmas trees will lead to production gapa and are not conducive to the coordinated development of gas fields.In response to this problem.the main controlling factor that caused the rise of the Christmas tree was found by using the neural network method,On this basis,by studying the characteristics of natural gas,a throttling and pressure reduction scheme was proposed,a wellbore temperature model was established.and a downhole choke tool suitable for high-temperature gas wells was designed and manufactured,After the tool was successfully implemented on site,it effectively reduced the temperature of the welbore,reduced the rise of the Christmas tree,and ensured production safety while increasing the single well productivity by 170000 m^(3)/d.Through the above research,a set of downhole throttling process design schemes for different high-temperature gas wells and different production periods of the same high-temperature gas wel is summarized and formed,which ensures the safe production of high-temperature gas wells and realizes the high efciency production of single well and the collaborative development of gas fields.This paper has a good guiding significance for the development of high-temperature gas fields.