龙羊峡水电站左岸坝肩尾工超深定向排水孔施工控制技术

龙羊峡水电站左岸坝肩尾工4个孔径130 mm、孔深80 m超深倾斜定向排水孔工程，从坝肩EL2610全部钻通至EL2530排水廊道（2 m×2.5 m)理论设计终孔点。采用瑞典Atlas-A32型潜孔钻机施工。针对该钻机钻具偏垂度3%的困难（同时也验证了其偏垂度3%的科学性），从技术参数控制和施工工艺控制上克服了潜孔钻施工超深定向孔偏垂度过大的技术“瓶颈”，总结出了瑞典进口Atlas系列潜孔钻机冲击回转钻具施工超深定向孔的技术成果，为国内不同行业同系列Atlas系列钻机施工超深定向孔提供了参考依据。

Construction Control Technology of Ultra-deep Inclined Directional Drainage Holes in Left Bank Abutment of Longyangxia Hydropower Station

Imported from Sweden, Atlas-A32 down-the-hole drill was used in 4 ultra-deep inclined directional drainage holes with diameter of 130 mm and depth of 80m in the left bank abutment of Longyangxia hydropower station, drilling from abutment EL2610 to the theoretical design borehole bottom location EL2530 drainage gallery(2m×2.5m). According to the difficulties caused by drilling tool vertical deviation of 3% (vertical deviation of 3% is verified to be scientific). The technical bottleneck of too large vertical deviation in ultra-deep directional hole construction with down-the-hole drill were overcome on the control of technical parameters and technology. The paper summarizes technical achievements of ultra-deep inclined directional holes constructed with Atlas series down-the-hole rotary percussion drill from Sweden.