Patent ID: 6435288
Filing Date: 2002-08-20
Classification: E21B

Abstract:
A rock drill bit comprising:a main body arranged to be attached at the end of a shaft of a drilling assembly, the main body having a diameter larger than that of the shaft; the main body having a front face arranged to engage an area for drilling; the main body having an outer surface extending rearwards from the front face and defining a recessed relief area of reduced diameter spaced from the front face and adjacent the shaft; a flush channel extending through the main body to the front face; the flush channel having at least one open end of the flush channel at the front face which is arranged to provide a flushing fluid from the shaft to an area at the front face; a plurality of contact points on the front face for engaging the area; at least one flushing groove extending along the outer surface from the front face to the recessed relief area for communicating flushing fluid from the front face for return along an outside of the shaft and, at least one relief bore extending through the main body from a mouth on the front face spaced inwardly from the outer edge rearwards to the recessed relief area behind the outer surface for providing a release for the fluid from the front face to the recessed relief area.