The borehole of Guanzhuang gold field in Yuanling was drilled with high inclination(45°), complex rock lithology, 10-70m fracture zone, serious leakage and block-falling. Drilling bit, construction technology, mud configuration and confection process were studied and selected to avoid the accidence in borehole with satisfied core recovery and increased drilling efficiency.
胡家农,余异非.湖南沅陵官庄金矿大斜度钻孔施工工艺[J].钻探工程,2009,36(3):4-6. HU Jia-nong, YU Yi-fei. Drilling Technology of Large-angle Borehole in Guanzhuang Gold Mine of Hunan[J]. Drilling Engineering, 2009,36(3):4-6.