Test Center, China Coal Research Institute Co., Ltd. Mine Safety Branch, China Coal Research Institute Co., Ltd.
State Key Lab of Coal Mining and Clean Utilization

针对裂隙发育区瓦斯抽采钻孔封孔质量差、抽采效率低的难题,发明了一种新的钻孔封孔方法。该方法以“两堵一注”封孔技术为基础,提出了高压吹送与负压抽采联合送粉技术,实现了封孔粉料的高效运输,完成了目标段的粉料预制充填;进行水泥砂浆封孔作业,分步完成钻孔封孔。现场应用结果表明:新的钻孔封孔方法较传统的水泥砂浆封孔方法有明显的技术优势,大幅提高了瓦斯抽采浓度(高达83.2%)和抽采混量(23.8 m~3/min),有效遏制孔外漏气的现象,明显降低了煤层的结构损伤。

According to the present situation of the poor borehole sealing quality and low gas pumping efficiency in coal seam, A new method of borehole sealing W as proposed.This method was based on the borehole sealing technology of exhaust flling with closed hole, the combined feeding technology of high pressure blowing a nd negative pressure pumping was put forward, the efficient transportation of sealing powder was realized, and powder flling in the target section was completed.Ceme nt mortar sealing operation was carried out after that, and drilling sealing was completed step by step.Field application results show that the new borehole sealing meth od had obvious technical advantages compared with the traditional cement mortar sealing method, the gas concentration ( up to 83.2%) and the pure gas extraction cap acity ( 23.8 m3/min) were improved greatly, but also the leakage phenomenon outside the hole was effectively suppressed, and the structural damage of the coal seam was reduced obviously.