Based on the analysis of gas source at the working face with "three-soft" unsteady coal seam, the authors introduce the principle and method of gas suction by roof-rock drilling.
2
目前在瓦斯抽放中急待解决的问题是软煤层瓦斯抽放的打钻技术,尤其是深孔打钻技术。
At the present, the problem which is urgently to be solved in gas discharge is the drilling technology in soft coal seam gas discharge, especially the drilling technology of the deep hole.