Sub-assembly for dust suppression in rock drilling
AssigneesChristopher Richard Carrall, David Thomas Hanns, Jo-Ann Nicol
InventorsDavid T. Hanns, Christopher R. Carrall
Life of this patent
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Abstract
This invention concerns an accessory, to be inserted in a drill string behind a drill bit, to provide separation of the liquid and air components of a flushing medium. The accessory comprises an inner housing (36) within an outer housing (34). A liquid/gas medium enters through opening (50) onto spiral raceway (48). Holes are provided at intervals along spiral (42). Liquid in the medium is centrifuged by the spiral (42) and projected into the chamber between inner and outer housings (36,34). The expelled liquid (52) falls to the base (70) of the housing (34) where it passes through apertures (38) into the drill bore. Once the medium has traversed the spiral (42) essentially only gas remains to pass through the opening (62) to the drill bit.
Claims8
A dust suppression sub-assembly for a rock drill comprising:
- means to secure the sub-assembly into a drill string;
- an outer housing and an inner housing;
- a helical path extending through the interior of the inner housing;
- inlet means for a gas and liquid flushing medium at one end of the sub-assembly, communicating with the helical path;
- a plurality of slots at intervals along the inner housing communicating between the interior of the inner housing and a chamber defined between the inner and outer housings;
- a plurality of outlets for the liquid in the outer housing adjacent the other end of the sub-assembly;
- and
- exit means for the gas at the other end of the inner housing communicating with the helical path.
Dependencies are inferred from the claim text.