关键词: 大口径钻孔, 空气钻进, 气举反循环, 潜孔锤钻进, 反循环钻进

Abstract: In view of the problems of hard to discharge residue and low efficiency of rock breaking，the large caliber reverse circulation drilling technology was studied.Basic conditions for the establishment of reverse circulation was analyzed，and 3 kinds of sealing methods including the ejector type，multilayer rubber chip type，and double sealing of hole bottom and entrance，and their application were introduced.Based on the double sealing method of hole bottom and top，2 kinds of large diameter reverse circulation DTH hammers with specifications of 311 mm and 580/311 mm and their supporting devices for entrance sealing were developed.The on-site application showed that this method can establish and maintain reverse circulation channel with good discharge effect and high drilling efficiency.It is worthy to be further popularized to large diameter drilling in mines.

Key words: Large-diameter drilling hole, Gas drilling, Air-lift reverse circulation, DTH drilling, Reverse circulation drilling