Abstract: The present invention is a rotary drill bit locking mechanism comprising a support spindle and a cutter cone with bearing surfaces. Furthermore, first and second annular grooves are formed on the bearing surfaces of the support spindle and the cutter cone that are radially adjacent to each other when the cutter cone is secured onto the support spindle. Additionally, a holding ring having a plurality of segments is assembled into the first and second annular grooves to secure the cutter cone into a rotatable position on the support spindle. Further, there is means for biasing the segments of the holding ring into a ring-like configuration in the annular grooves. This invention thus provides a rotary drill bit locking mechanism for holding a cutter cone onto the support spindle that is easy to manufacture and assemble.

Abstract: Improvement in the drilling of vertical bore holes is achieved by an asymmetrical rotary cone bit having a substantially cylindrical body with a shank formed on the body and extending therefrom along a vertical axis for connection to a drill string. Projecting from the cylindrical body are three journal pins, which pins extend from the end of the body opposite from the shank. These three journal pins are circumferentially displaced such that the rotational axis of the first and second pins are displaced more than 120 degrees and less than 180 degrees. The axis of the third journal pin is circumferentially displaced equidistant from the axis of the other two journal pins. Journaled on the first and second journal pins are first and second roller cutter cones having substantially the same based diameter. Each of these cutter cones has cutting teeth extending from the surface thereof and includes a row of gage cutting teeth.

Abstract: The invention includes a low-friction seal assembly for use with a rotary drill bit having bit cutters manufactured by casting. The seal assembly includes a seal element having a bellville spring element surrounded by an elastomeric material. The seal element is secured for rotation with the bit cutter by pitted surfaces of a securing groove formed in the cutter, adhesive, and/or by roughening the surface of the bit cutter contacting the seal element.

Abstract: A drill bit having a nozzle for drilling fluid to pass out of the drill bit and into the bore hole is disclosed. In one embodiment two diagonal passages through the nozzle impart angular momentum to the drilling fluid. In another embodiment, four diagonal passages through the nozzle impart angular momentum. In still another embodiment, a central bore hole through the nozzle has helical grooves along its internal orifice wall to impart angular momentum. The angular momentum causes the drilling fluid exiting from the interior of the drill bit to flow downward into the bore hole in a divergent vortex that sweeps the cuttings away from the cutting surfaces of the drill bit.

Abstract: The present invention relates to a drill bit incorporating one or more rotary cutters. The rotary cutters are supported for rotation by a bearing assembly including ball bearings running in races in the rotary cutter and drill bit body. The bearing assembly further includes an annular bushing. A sealing assembly including an O-ring seal is provided to seal lubricant within the bearing assembly and prevent external contaminants from entering the bearing assembly. A corrosive environment has been found to increase the occurrence of stress fractures in the areas above the juncture of cutter supporting structure and the bit body. It has been found that a sacrificial anode partitioned about the surfaces of the juncture renders the surfaces cathodic and resist stress fracture.

Abstract: The present invention relates to a drill bit (10) incorporating one or more rotary cutters (14). The rotary cutters (14) are supported for rotation by a bearing assembly including ball bearings (28) running in races (24, 26) in the rotary cutter and drill bit body (20). The bearing assembly further includes an annular bushing (34). A sealing assembly (36) including an O-ring seal (38) is provided to seal lubricant within the bearing assembly and prevent external contaminants from entering the bearing assembly. Corrosion has been found to destroy the seal surfaces (42, 44) against which the O-ring seal acts (38). It has been found that plating the sealing surfaces with a material passive to the electrochemical system or higher in the electromotive series than the material forming the sealing surfaces reduces corrosion. Alternatively, a sacrificial anode (68) is provided about the sealing surfaces to render the surfaces cathodic and resist corrosion.

Abstract: A rotary drill bit for use on a rotating drill string includes a solid forged unitary main body having a plurality of downwardly facing hemi-cylindrical body surfaces. A plurality of cutter bases are provided, each cutter base including an upwardly facing hemi-cylindrical base surface that is fused to one of the body surfaces by electron beam welding. Each cutter base includes a bearing pin extending inwardly with respect to the bit. A cone shaped cutter is rotatably mounted on the bearing pin for rotating about the bearing pin during drilling operations to bore through earth formations.

Abstract: A cable tool (10) includes a tool bit (12), a drill stem (14) and an adapter (16). Openings (32) are formed in a cutting face (18) of the tool bit (12) and inclined bores (34) extend upwardly within the tool bit (12) to an upwardly extending bit passageway (36). A retention chamber (46) is formed in the drill stem (14) communicating with the bit passageway (36) for storing rock and earth particles. An adapter passageway (52) communicates with the retention chamber (46) and includes a liquid drain (24) to drain water from the adapter passageway (52) and the retention chamber (46). Optionally, a flapper valve (64) may be mounted within the retention chamber (46) adjacent the bit passageway (36).

Abstract: A filament wound bearing infiltrated with an antigalling material is constructed by winding a filament (42) on a mandrel (46) to form a crisscrossed pattern of a bearing structure (40). The bearing structure (40) is diffusion bonded in a furnace (58) and subsequently densified between mandrels (66, 68). Following densification, the bearing structure (40) is again diffusion bonded in the furnace (58) to provide flat wound strips bonded together to form a load supporting core. This core is placed in a crucible filled with an infiltrate antigalling material and heated in a vacuum atmosphere in the furnace (58) to cause the infiltrate to fill the pores of the bearing structure (40) by means of capillary action. The final bearing structure comprises a crisscross pattern of flattened filaments bonded together at crossover points where the pore size and pore spacing are controlled to provide a desired density.

Abstract: A rotary drill bit for use on a rotating drill string includes a solid forged unitary main body having a plurality of downwardly facing hemi-cylindrical body surfaces. A plurality of cutter bases are provided, each cutter base including an upwardly facing hemi-cylindrical base surface that is fused to one of the body surfaces by electron beam welding. Each cutter base includes a bearing pin extending inwardly with respect to the bit. A cone shaped cutter is rotatably mounted on the bearing pin for rotating about the bearing pin during drilling operations to bore through earth formations.