可循环泡沫钻井液研究与应用

Study and application of recoverable foam drilling fluid

胜利油田的草桥、孤南、桩西、临盘等地区的古潜山地层,连通性好,孔隙度高,裂缝、溶洞发育。钻井过程中极易发生严重的井漏,有的井甚至造成报废。研究了可循环泡沫钻井液体系,并在室内对该体系的性能、稳定性、抗污染能力及油气层保护等性能进行了评价。现场29口井的应用表明,可循环泡沫钻井液体系具有一定的稳定性,密度低(0.60—0.90 g/cm^3),携砂性能好。解决了胜利油田古潜山地层易漏问题,减少了钻井液对油层的损害,降低了钻井成本,提高了原油产量,获得了良好的经济效益。

Lost circulation is likely to take place in fractured carbonate zones with low formation pore pressure, suitable drilling fluid system should be used. A recoverable foam drilling fluid was developed and evaluated, field using in Shengli Oilfield proved its advantages of good stability, low density and good cutting carriage capability. The system is 'suitable for drilling wells with lost circulation potentials, as well as in underbal-anced drilling.