Aiming at the gas drainage problems with bedding drilling in soft coal seam,such as shallow sealing depth,tight sealing hole and so on,leading to poor pumping effect.Through analyzing the drilling stability and stress field of surrounding soft coal seam,the reasonable sealing depth of grouting hole sealing in soft coal seam was determined.By increasing borehole pressure to the hole wall,sealing filling fissure effectively,the paper proposed the grouting technology in soft coal seam.In the application in Baoan Coal Mine,during the 60 days inspection period,the average gas concentration of test hole increased more than 30%,the effect of drainage and hole sealing in soft coal seam was greatly improved.%松软煤层顺层钻孔瓦斯抽采普遍存在封孔深度不合理、封孔不严等问题,抽采效果差.针对以上存在的问题,文章从松软煤层钻孔稳定性及巷道围岩应力场分析出发,确定了松软煤层钻孔合理封孔深度;并通过增大钻孔内压力对孔壁施加主动支撑,封堵充填钻孔孔壁裂隙,提出适用于松软煤层顺层钻孔带压注浆封孔技术.通过保安煤矿现场应用显示,在60d的考察期内试验钻孔平均瓦斯浓度提高30%以上,显著提高松软煤层顺层钻孔封孔的密封性和抽采效果.
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