TKP194-80型密闭保压取心工具的研制与应用

Development and application of TKP194-80 sealed pressure⁃holding coring tool

密闭保压取心是一种能够保持或接近地层压力的特殊取心技术,可使岩心中流体、气体保持在原始状态。这种技术对于正确认识地质情况、计算油田可采储量、分析页岩气藏和煤层气藏机理,制定勘探开发方案有着十分重要的意义。研制TKP194-80型密闭保压取心工具,采用大通径高压球阀密封、密闭液封堵、液压差动、活塞压力补偿等关键技术,配有岩心冷冻、切割、集气等岩心后处理工艺,钻头外径215 mm,保压能力50 MPa,岩心直径80mm。在山西晋中某煤层气资源地质探井开展保压取心应用,共进行保压取心8筒,总进尺37.51 m,岩心采取率84.4%,保压成功率87.5%。研究结果表明,该取心工具保压性能可靠,技术方案可行,可为常规油气及非常规油气藏勘查开发提供技术装备支撑。

Closed pressure maintaining coring is a special coring technique that can maintain or approach formation pressure,allowing fluid and gas in the core to remain in their original state.This technology is of great significance for correctly understanding geological conditions,calculating recoverable reserves of oil fields,analyzing the mechanism of shale gas and coalbed gas reservoirs,and formulating exploration and development plans.TKP194-80 type sealed pressure maintaining coring tool is developed,which adopts key technologies such as large bore high pressure ball valve sealing,sealing fluid plugging,hydraulic differential migration,piston pressure compensation,and is equipped with core post‑processing processes such as core freezing,cutting,and gas gathering.The outer diameter of the drill bit is 215mm,the pressure maintaining capacity is 50MPa,and the core diameter is 80mm.The application of pressure retaining coring was carried out in a coalbed methane resource geological exploration well in Jinzhong,Shanxi province.A total of 8 pressure retaining coring barrels were carried out,with a total footage of 37.51m.The core recovery rate was 84.4%,and the pressure retaining success rate was 87.5%.The research results show that the coring tool has reliable pressure retaining performance,feasible technical scheme,and meets the design requirements.It can provide technical equipment support for the exploration and development of conventional and unconventional oil and gas reservoirs.