Abstract: A rotary drag bit has one or more fixed composite cutting structures formed from a plurality of discrete prefabricated cutters that abut each other along complementary side surfaces, the composite cutting structure being placed and oriented on the cutting face of the rotating body so that the composite cutting structure presents a cutting profile that does not expose any portion of the cutting face that is between or behind the composite cutting structure, with respect to the direction of travel of the composite cutting structure during boring, to the uncut earth formation as the body is rotated during boring.

Abstract: A fixed cutter drill bit that includes one or more integrally-mounted rotating disc with cutters around the circumference of the disc. Each disc is mounted to bearings to handle the torque generated and the weight on bit required to cut the formation. The mounting angle of the disc generates a torque causing the disc to rotate. As the disc rotates, new cutters are presented to the formation. The discs may vary in size, mounting location and number so as to cover entire bladed or just a certain portions of blades. The exposure of the disc could also be set to enable it to rotate while under load, e.g., the cutters on the outside of the bit may contact the formation while the inner half of the disc is protected by a fixed blade.

Abstract: A downhole tool having a progressive cavity mud motor with an impact generator disposed within the mud motor rotor or bearing assembly. In one embodiment, the impact generator includes a mud turbine connected to a eccentric ring that encircles and periodically strikes an anvil surface of a percussion shaft. The eccentric ring is pivotable between an engaged striking position and a disengaged non-striking position. The percussion shaft is coupled to a drill bit though a splined connector that provides limited slip for transmitting rotation of the mud motor rotor to the drill bit and for transmitting percussion strikes against the anvil to the drill bit without the need to accelerate the entire drill string.

Abstract: A fixed cutter drill bit that includes one or more integrally-mounted rotating disc with cutters around the circumference of the disc. Each disc is mounted to bearings to handle the torque generated and the weight on bit required to cut the formation. The mounting angle of the disc generates a torque causing the disc to rotate. As the disc rotates, new cutters are presented to the formation. The discs may vary in size, mounting location and number so as to cover entire bladed or just a certain portions of blades. The exposure of the disc could also be set to enable it to rotate while under load, e.g., the cutters on the outside of the bit may contact the formation while the inner half of the disc is protected by a fixed blade.

Abstract: A downhole tool having a progressive cavity mud motor with an impact generator disposed within the mud motor rotor or bearing assembly. In one embodiment, the impact generator includes a mud turbine connected to a eccentric ring that encircles and periodically strikes an anvil surface of a percussion shaft. The eccentric ring is pivotable between an engaged striking position and a disengaged non-striking position. The percussion shaft is coupled to a drill bit though a splined connector that provides limited slip for transmitting rotation of the mud motor rotor to the drill bit and for transmitting percussion strikes against the anvil to the drill bit without the need to accelerate the entire drill string.

Abstract: A rotary drag bit has one or more fixed composite cutting structures formed from a plurality of discrete prefabricated cutters that abut each other along complementary side surfaces, the composite cutting structure being placed and oriented on the cutting face of the rotating body so that the composite cutting structure presents a cutting profile that does not expose any portion of the cutting face that is between or behind the composite cutting structure, with respect to the direction of travel of the composite cutting structure during boring, to the uncut earth formation as the body is rotated during boring.

Abstract: A pack-off bushing for placement inside an outer conduit while a fluid is passed through an inner conduit positioned within the outer conduit. The bushing includes a mandrel having a mandrel passage extending axially therethrough, a housing carried on the mandrel and capable of axial movement relative to the mandrel and a balancing system associated with the mandrel and the housing for applying a balancing force to the mandrel to oppose an axial mandrel force applied to the mandrel.