Rock drilling method and apparatus utilizing high pressure water jets for drilling holes of relatively small diameter at speeds significantly greater than that attainable with existing drilling tools. Greatly increased drilling rates are attained due to jet nozzle geometry and speed of rotation. The jet nozzle design has two orifices, one pointing axially ahead in the direction of travel and the second inclined at an angle of approximately 30° from the axis. The two orifices have diameters in the ratio of approximately 1:2. Liquid jet velocities in excess of 1,000 ft/sec are used, and the nozzle is rotated at speeds up to 1,000 rpm and higher.
D. A. Summers et al., "Method and Apparatus for Water Jet Drilling of Rock," U.S. Patents, Jan 1978.
Patent Application Number
© 1978 The Curators of the University of Missouri, All rights reserved.
01 Jan 1978