Rational Modes of Inertial Impact Fracture of Rocks

The article describes inertial impact fracture of geomaterials using a rotary hammer. The capabilities of the tool in underground large-hole drilling are discussed. The authors present the procedure and results of the lab-scale testing of influence exerted by different combinations of rotational and linear path velocities of the rotary hammer on the strength of current taken by working tools and on the shock vibration velocity of supporting members of the rotary hammer. The rational ranges of these velocities, such as the process of fracture runs at the least energy input and minimum impact on the working tools, are determined.