Abstract: A drill bit for drilling into underground formations is disclosed, the drill bit having conduits for providing either lubricant or gaseous drilling fluid to the cutting cone bearings. In an alternate mode of operation, a mixture of lubricant and gaseous fluid is supplied to the bearings.

Abstract: A drill bit assembly for a rotary drill having a source of fluid under pressure and three bearing mounted rotary cutting cones for drilling into relatively hard material comprises an elongated housing with a first end adapted for engagement with the drill and a second end including the cutting cones or tools for engagement with the material to be drilled. A plenum chamber is provided within the housing for receiving pressurized fluid and for dividing the pressurized fluid into three portions. A first portion of the pressurized fluid is directed downwardly for impringement upon the material being drilled to pick up and remove dust and cuttings from the vicinity of the cutting cones. A second flow of the pressurized fluid is directed upwardly to remove the dust and cutting cones from the drill hole. The third flow of fluid is directed through the cutting cone bearings to cool the bearings during the drilling operation.

Abstract: A drill bit assembly has an elongated housing in which a drill is provided with a generally cylindrical shape for receiving an enlarged tool end with somewhat greater diameter, the tool having cutting cones for cutting a drill hole in material to be drilled. Air is fed to a plenum chamber within the housing out of which are fed two air flows. The first flow is directed to the region of the cutting cones and is of reduced magnitude sufficient only for removing dust and cuttings away from the bit assembly up along the sides of the bit. A plurality of vanes are provided on the housing to direct the first flow into a helical path the general pitch of the vanes. The vanes are caused to overlap one another in the direction of flow.

Abstract: In order to prevent the moisture in the general air supply from entering the first flow and generating mud in the area of the cones of a drill bit assembly, separator means is provided within the plenum chamber supported on the housing walls proximate to the conduit through which a first flow path flows. This may be done by using a stand pipe supported on an orifice plate of the first conduit and extending above the openings of a second conduit. Perforations in the stand pipe are above the second conduit. A fluid flow diverter at the end of the stand pipe is preferably of conical shape, larger diameter than the stand pipe and arranged so that its edges extend below some of the perforations on the stand pipe so that air entering the first flow must reverse course to pass through the perforations. Water cannot readily reverse in this manner.

Abstract: A method and apparatus for providing a flow of lubricating fluid from a surface-mounted lubricating fluid source through a rotatable drill pipe to rotary cutting cones of a rotary drill bit for drilling in an underground formation, including pump means for providing a flow of lubricating fluid from the fluid source to an end of the drill pipe. Drill pipe conduit means extending along the length of the drill pipe is provided for receiving the flow of lubricating fluid and for directing the lubricating fluid flow along the drill pipe to the drill bit. Distribution conduit means at the drill bit extends from the drill pipe conduit means to the cutting cones and receives the flow of lubricating fluid from the drill pipe conduit means for directing the lubricating fluid flow to the cutting cones for lubrication thereof.