抽水蓄能电站斜井导孔施工关键技术研究

抽水蓄能电站斜井开挖多采用反井钻井法,而导孔钻进作为反井钻井施工的第一道工序,钻孔的精度、成孔质量直接影响后续斜井工程的成败。通过引用煤炭行业斜井专用钻机、优化调整不同钻进层段钻具组合、无线随钻测线仪+螺杆钻具的高精度轨迹控制技术及钻井液护壁技术,成功完成一条斜长295.6 m、终孔偏斜率仅为0.45%的导孔,导孔轨迹平滑且精确入靶,为后续抽水蓄能电站斜井工程施工提供了宝贵经验。

Study on Key Technology of Pilot Hole Construction in Inclined Shaft of Pumped-storage Power Station

The raise boring method is often used in inclined shaft excavation of pumped-storage power station,and the pilot hole drilling is the first procedure of raise boring construction.The accuracy and quality of pilot hole drilling directly affects subsequent inclined shaft construction.A pilot hole with an inclined length of 295.6 m and a deviation rate of only 0.45%is successfully completed by using the special drilling rig for inclined shaft in coal industry,optimizing and adjusting the BHA of different drilling intervals,high-precision trajectory control technology of wireless line while drilling instrument and screw drilling tool,and drilling fluid wall protection technology.The trajectory of pilot hole is smooth and accurate,which provides valuable experience for the construction of inclined shaft of pumped-storage power station.