During the drilling of large diameter gas drainage borehole targeted at coal No.15 in the Shanxi Wangyun coalmine has inter⁃sected abandoned workings in coal No.3, thus increased the risk and difficulty in drilling and sequential mining of coal No.15. There⁃fore, a circle of 6m radius curtain grouting boreholes radiated from the drainage borehole drilled, after the grouting of them has formed a water plugging curtain around, then resume the drilling of drainage borehole, finally carried out casing isolation of abandoned workings and provided a“double security”for gas drainage borehole drilling. The method not only ensured subsequent drilling, meanwhile elimi⁃nated the impacting on mining of coal No.15 from coal No.3 abandoned workings water ponding, thus provided experience and refer⁃ence for similar project construction henceforth.%山西望云煤矿在矿区内施工目的层为15号煤层的大口径瓦斯抽放孔过程中，钻遇3号煤层老窑采空区，为瓦斯抽放孔施工和后续15号煤层开采增加了风险和难度。首先通过地面钻探方式在瓦斯抽放孔半径为6 m的采空区施工一圈帷幕孔，在帷幕孔注浆后使得瓦斯抽放孔周围形成帷幕堵水的效果，进而施工瓦斯抽放孔，最后再用套管对采空区进行隔离，为后续瓦斯抽放孔施工提供了“双保险”。确保了后续瓦斯抽放孔的顺利完工，同时消除了3号煤层采空区积水对后续15号煤层开采的影响，为今后类似工程施工提供经验和借鉴。
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