Abstract: The drilling system of this invention provides a drill mast mounted on a turntable. The turntable may be mounted on any type of undercarriage or carrier. The drill mast can be positioned around the perimeter of the turntable, it can be positioned near to, or away from, the turntable. The drill mast is carried on a trunnion mounting and can be oriented along Y and Z axis' with respect to the turntable X axis for drilling angle holes. A pipe joint breaker assembly is provided adjacent the lower end of the drilling mast. This assembly can accommodate different size pipe diameters. The drilling systems of this invention is specially adapted to reverse-circulation sample drilling employing a down-the-hole hammer drill. The drilling head configuration provides for simultaneous feeding into a multi-walled drill string of drilling mud, compressed air into the drill string to operate the hammer drill and to feed the hammer drill bit head, and withdrawing of sample-containing return air.

Abstract: The drilling system of this invention is specifically adapted to reverse-circulation sample drilling employing a downhole hammer drill. The drilling head configuration provides for simultaneous feeding into a multi-walled drill string with drilling mud, compressed air to operate the hammer drill, to feed the hammer drill head and withdrawing of the return air. The system includes a triple-walled drill rod especially adapted for downhole hammer drilling that eliminates the need for a separate drive casing string.