Accurate Directional Water Detection and Water Release Technology for Underground Coal Mine

For the problem of dead zone caused by short distance and low accurate water detection and release hole in roof and goaf of traditional mine, we carry out technique reseach including the opening of directional water detection and release hole, the installing of orifice equipments, the drilling directional water detection and release hole, drainage of end hole, based on screw motor deflecting directional drilling technology. This forms a set of water detection and release construction technique. The construction technique achieves such goals including accurately controlling of long drilling to get the target prospecting area, the branch hole technology that increasing the prospecting area, draining water of goaf hydrops and productive aquifer effectually. In the field experiments, seven goal relief holes were completed and draining water 3 million m³ in Nixia Shitanjing Mine. Among these constructions, the maximum depth in three productive aquifer water prospecting holes in China Coal Muduchaideng Mine achieves 708 m, which showed that the technology could be applied over the depth of 700 m to improve the prospecting area and precision, ensure the safety of mine construction effectually.