摘要 |
<p>A rock bit used for drilling with air as the circulating fluid, and a centrifugal separator to filter liquid and other contaminants from the air diverted to the bit bearings. The filter generates a fluid vortex with radial vanes, each having plural pitches, located within the shank of the bit. Bearing coolant passages, located beneath the separator, receive filtered air from a central, filtered air location. The vortex centrifugally forces the water and other contaminants outwardly into nozzle passages that direct fluid toward the bottom of the borehole.</p> |