深孔凿岩 meaning in Chinese

deep drilling
long blast drilling
long-hole drilling

Model tc308 high pressure crawler type down hole drill rig for open use
中高风压潜孔钻机在中深孔凿岩中的试验应用
Abstract : this paper made an approach to the form and cause of the failure of large diameter long - hole rock drilling tools in anqing copper mine and put forward some ways for extending the service life of rock drilling tools in the light of its practical use
文摘:文章主要就安庆铜矿大直径深孔凿岩钻具的失效形式和原因进行了探讨，并从钻具使用角度出发提出了提高凿岩钻具使用寿命的途径。