Fast drilling technology and development tendency of hard rock in underground coal mine

In order to solve the problems of low drilling efficiency, slow hole forming rate, long construction period and low life of drilling tools during dilling hard rock in underground coal mine, fast dilling technology with auxiliary rock-breaking tools has been widely applied in mine water management borehole and high level borehole , which made important progress in many coal mines in China. According to the development of dilling technology for hard rock in underground coal mine, the paper introduced the fast dilling technology of hard rock in the underground coal mine combined with low pressure valve hydraulic hammer ，fluidic hammer with high impact energy and hydraulie torque impactor three kinds of auxiliary rock-breaking tools and stated each principle, technical features and application situation.The paper summarized the developrment progress and shortages existed in low pressure valve hydraulic hammer, fluidic hammer with high impact energy and hydraulic torque impactor. Combining with the speific application of the above three kinds of dilling tools in the mining areas，the paper pointed out the problems and causes in the process of drilling hard rock in the underground coal mine, and also proposed targeted solutions. Finally, the paper pointed out the development direction of the fast drilling technology of hard rock in the underground coal mine and provided relevant suggestions to accelerate the development of directional dilling technology in the underground coal mine, which also provided reference for the development of hard rock drilling technology in underground coal mine.