微泡沫钻井液在川渝地区玉皇1井的应用

APPLICATION OF MICROFOAM DRILLING FLUID IN WELL YUHUANG-1 IN SICHUAN-CHONGQING REGION

微泡沫钻井液以其密度可调、流变性好、能反复泵送、可循环使用、不需要额外添加设备、成本低而获得广泛应用。许多油气田已成功应用该技术解决了低压地层和长段破碎带地层井漏的难题,取得了良好的技术和经济效益。但对地层压力系数低且裂缝较大的严重井漏往往失去作用。为了拓宽微泡沫钻井液的应用领域,针对川渝地区玉皇1井表层井段的严重井漏,交替使用微泡沫钻井液和微泡沫桥浆,使井漏得到了有效控制。与邻区同类井相比,钻井速度提高了3～7倍,取得了明显的技术经济效益,为处理类似井漏问题提供了新的技术途径。

Microfoam drilling fluid has been widely applied because of its density adjustability, good rheological property, being repeatedly pumped up and circularly utilized, existent equipment's being used only, and low drilling cost. Through applying such a technique, the difficulty in lost-circulation at the low-pressure zone and long-interval broken formation has been resolved and good technical and economic results were achieved in many oil and gas fields. However, its function was often lost upon the serious circulation loss occurring to the formation with low pressure coefficient and relatively macro fractures. The serious circulation loss of surface interval in well Yuhuang-1 in Sichuan - Chongqing region was effectively controlled through alternating utilization of microfoam drilling fluid and microfoam bridging mud. As compared with the same kind of wells at the neighbouring areas, the drilling speed of the well has increased by 3 - 7 times, technical and economic results being obvious, thus providing a new technical method for treating the same kind of lost circulations.