Abstract: The invention concerns a seal assembly (1) for sealing between a fixed member (10) and a rotatable member (3) adapted for rotating around an axis in relation to said fixed member. The seal assembly comprises a first ring member (4) adapted for being fitted in or on said fixed member circumferentially around said axis and having a first surface (34); a second ring member (6) adapted for being fitted circumferentially in or on said rotatable member and having a second surface (36) facing said first surface along a length; and a third ring member (7) between said second and said first surface, the distance between said second surface and said first surface being larger at the middle of said length and becoming smaller towards the extremities thereof.

Abstract: A drill bit includes a bit head having a front face, a plurality of blades extending along at least a portion of the front face, the blades comprising cutters, a cavity for forming a core, the cavity being approximately centrally located in the front face of the bit between adjacent end portions of the plurality of blades, and a removable core breaking device disposed within the cavity. The core breaking device is configured to project toward the front face a distance to engage and destroy the so formed core into multiple smaller fragments prior to a core length exceeding a core diameter, or project toward the front face a distance to engage and break the so formed core into a substantially unitary core sample.

Abstract: A hammer assembly is actuated to drive an earth bit through a formation. The hammer assembly includes a piston, and a flow control tube which extends through the piston. The flow control tube includes drive and return guide ports. The piston is repeatably moveable relative to the drive and return guide ports in response to a fluid flow through the flow control tube. In this way, the hammer assembly is actuated.

Abstract: A method of boring through a formation includes providing a drilling machine and drill string and operatively coupling an earth bit to the drilling machine through the drill string. An air flow is provided through the drill string at an air pressure less than about one-hundred pounds per square inch (100 psi) and an overstrike force is applied to the earth bit, wherein the overstrike force is less than about five foot-pounds per square inch (5 ft-lb/in2).

Abstract: A method of boring through a formation includes providing a drilling machine and drill string and operatively coupling an earth bit to the drilling machine through the drill string. An air flow is provided through the drill string at an air pressure less than about one-hundred pounds per square inch (100 psi) and an overstrike force is applied to the earth bit, wherein the overstrike force is less than about five foot-pounds per square inch (5 ft-lb/in2).

Abstract: A method of boring through a formation includes providing a drilling machine and drill string and operatively coupling an earth bit to the drilling machine through the drill string. An air flow is provided through the drill string at an air pressure less than about one-hundred pounds per square inch (100 psi) and an overstrike force is applied to the earth bit, wherein the overstrike force is less than about five foot-pounds per square inch (5 ft-lb/in2).

Abstract: A hammer assembly is actuated to drive an earth bit through a formation. The hammer assembly includes a piston, and a flow control tube which extends through the piston. The flow control tube includes drive and return guide ports. The piston is repeatably moveable relative to the drive and return guide ports in response to a fluid flow through the flow control tube. In this way, the hammer assembly is actuated.

Abstract: A method of boring through a formation includes providing a drilling machine and drill string and operatively coupling an earth bit to the drilling machine through the drill string. An air flow is provided through the drill string at an air pressure less than about one-hundred pounds per square inch (100 psi) and an overstrike force is applied to the earth bit, wherein the overstrike force is less than about five foot-pounds per square inch (5 ft-lb/in2).

Abstract: A method of casehardening an earthboring tool component includes steps of providing an earthboring tool component and providing a semiconductor light emitting device carried by a mechanical arm. The mechanical arm is used to move the semiconductor light emitting device relative to the earthboring tool component. Light emitted by the semiconductor light emitting device is directed to a surface of the earthboring tool component so that it is casehardened.

Abstract: Hardfacing to protect wear surfaces of drill bits and other downhole tools having coated diamond particles dispersed within and bonded to a metallic matrix deposit. The coating on the diamond particles may be formed from materials and alloys such as particles, tungsten carbide, and tungsten carbide/cobalt and cermets such as metal carbides and metal nitrides. The coated diamond particles are preferably sintered and have a generally spherical shape. The coated diamond particles are premixed with selected materials such that welding and cooling will form both a metallurgical bond and a mechanical bond within the solidified metallic matrix deposit. A welding rod is prepared by placing a mixture of coated diamond particles, hard particles such as tungsten carbide/cobalt, and loose filler material into a steel tube.

Abstract: Hardfacing to protect wear surfaces of drill bits and other downhole tools having coated diamond particles dispersed within and bonded to a metallic matrix deposit. The coating on the diamond particles may be formed from materials and alloys such as particles, tungsten carbide, and tungsten carbide/cobalt and cermets such as metal carbides and metal nitrides. The coated diamond particles are preferably sintered and have a generally spherical shape. The coated diamond particles are pre-mixed with selected materials such that welding and cooling will form both a metallurgical bond and a mechanical bond within the solidified metallic matrix deposit. A welding rod is prepared by placing a mixture of coated diamond particles, hard particles such as tungsten carbide/cobalt, and loose filler material into a steel tube.

Abstract: An improved drill bit seal arrangement, including a seal ring having a boronized outer annular surface which is fabricated separate and apart from the journal bearing structure of the drill bit arm. The seal ring boronized surface is polished to define a smooth non-abrading surface for the elastomeric seal. The seal arrangement enhances the wear resistance of the seal between the drill bit arm and the cutting cone, thereby increasing the life span of the drill bit.

Abstract: A rolling cutter earth drilling bit in which integral one-piece pilot bushings provide both radial and thrust load sliding surfaces which incorporate an anti-galling material. A roller cone bit has three downwardly extending arm members which terminate in cylindrical spindles for the rolling cutters. Each spindle has a stepped configuration providing an enlarged journal section which is stepped down to provide an annular thrust shoulder and a reduced pilot pin which projects from the thrust shoulder. The rolling cutter mounted on the spindle has an enlarged rearward bearing recess which receives the journal section of the spindle and a reduced forward bearing recess which receives the spindle pilot pin. An annular thrust face corresponding generally to the spindle shoulder is between the recesses.

Abstract: A composite sintered rock bit insert for use in a rolling cutter is fabricated from two tungsten carbide components. The first component is formed of a tungsten carbide composite that is less wear resistant, but tougher, than the second component. The two components are joined at a parting plane which extends to an earth-engaging surface of the insert. The insert is mounted on a rolling cutter such that the component having the lower wear resistant properties is on the leading face of the insert. With this combination, the wear pattern of the insert maintains a crest-like configuration at its rock engaging surface.

Abstract: A rotary drill bit for drilling earth formations is disclosed having a plurality of cutting elements mounted on the head portion of the bit. The bit further includes a plurality of individual protrusions projecting from the head portion more than the extension of the cutting elements. The protrusions are fabricated of a metal more readily abraded by the earth formation than any of the cutting elements. The protrusions protect the cutting elements during handling of the bit and entry of the bit into a borehole; and, the protectors are abraded away to expose the cutting elements during drilling.

Abstract: A sealing system acts as a barrier to the drilling fluid, pulverized cuttings and other materials in the borehole preventing the materials from entering the bearing area of an earth boring bit and retains lubricant inside the bearing area. At least one bearing pin extends from the body of an earth boring bit and a rolling cone cutter is mounted on the bearing pin. A seal assembly is located in the mouth of the cutter between the cutter and the bearing pin. The seal assembly includes an annular rigid ring, an elastomeric ring and a deformable ring means mounted to rotate with said rolling cone cutter. The elastomeric ring is attached to the annular rigid ring. The elastomeric ring has a lip with a wiping surface that contacts the bearing pin. The deformable ring means is connected to the lip and maintains contact between the wiping surface and the bearing pin.

Abstract: An asymmetric gage row insert provides a larger amount of wall contacting surface thereby decreasing the wear on the gage insert and increasing the ability of the earth boring apparatus to maintain a full gage hole. The insert has a shape prior to assembly onto the earth boring apparatus that includes a base integrally joined to an asymmetric head. The base is mounted in a socket in the earth boring apparatus. The head projects from the earth boring apparatus and includes an extended gage cutting surface. The gage cutting surface is the largest plane surface on the head. The gage cutting surface contacts the wall of the hole with the majority of the length of its extended surface and with the same angle as the gage angle of the bit.