V.V. Lyukhanov, S.B. Alferov
Geological conditions of different ore mines are rather diverse, in many of them rock have such characteristics that the volume of compressed air supplied from a compressor in the process of drilling is not sufficient for intensive borehole clean-up. For instance, the presence of water with some minerals makes rock viscous and strong. Therefore, the Machine-Building Holding AO provides an adjustable feature of borehole additional flushing in the design of downhole hammer by way of plug replacement with choke. The proper choice of the required additional flushing air is regulated by choke size and compressed air pressure in the line. This dependence is described in the operation and maintenance manuals for each type of downhole hammer manufactured by the Machine-Building Holding AO.