Shenhua Geological Exploration Co.，Ltd., Beijing ，China

大斜度定向井技术具有可以钻穿更长的页岩气储层段、较大范围地探明和控制含气面积、大幅提高单井产气量等优点。在前期直井预探井工作的基础上,通过对井身结构、井眼轨迹、钻具组合、钻柱力学、钻井液、固井等技术的优化设计,优选出符合高陡构造区页岩气勘探的大斜度定向井钻井工程设计方案,建立了工区的地层压力剖面和钻头选型方案,在直井段采用防斜打直、造斜段开展复合钻井、目的层段引用旋转导向钻井、油基钻井液等技术,成功地钻成2口页岩气大斜度定向井,缩短钻井周期,提高钻井效率,实现了优快钻井,主力页岩储层钻遇率100%,形成一套页岩气高效开发的钻井技术体系,可为今后其他地区页岩气、煤层气的勘探开发提供借鉴。

The technology of high deviated directional well can be used to drill through a long shale gas reservoir, explore and control a wide range of gas-bearing area, and increase the production of single well and percentage recovery significantly. Based on the early exploration of vertical drilling, through the optimum design of well structure, borehole trajectory, drill assembly, friction torque, drilling fluid system, cementing technique, we selected the drilling scheme of high deviated directional well suitable for the efficient development of shale gas, established the formation pressure profile of Baojing area and completed the bit type selection. By applying the deviation control while drilling vertical straight well, compound drilling within building up section, and rotating steering drilling technique within the target section, two high deviated directional shale gas wells were constructed successfully with the drilling rate of shale formation being 100%. The technology system developed here which is for the efficient high deviated directional drilling, obviously increase the rate of penetration, shorten the drilling cycle, and achieve the goals of safe and efficient drilling, and thus provide a reference on the future exploration and development of shale gas and coalbed methane in other areas.