Abstract: In one aspect, an apparatus for use in a wellbore is disclosed, including: an inlet; an outlet; and a variable flow restriction configured to provide a predetermined constant pressure drop between the inlet and the outlet in response to a range of inlet flow rates. In another aspect, a method for providing a fluid flow within a wellbore is disclosed, including: providing the fluid flow to an inlet; restricting the fluid flow to provide a predetermined constant pressure drop between the inlet and an outlet in response to a range of fluid flow rates; and providing the fluid flow to the wellbore from the outlet.

Abstract: An alignment device for a sliding sleeve in a housing in a tubular string features a patterned alignment ring that remains stationary. The sliding sleeve in one of its end positions has a mating profile such that profile misalignment results in profile alignment as the sliding sleeve is axially advanced toward the alignment ring. In a choke application the fully closed position of the choke brings the profiles together to induce relative rotation into an aligned configuration of the ports on the sliding sleeve with the ports on the surrounding housing. Misalignment can occur when tools are run through the sliding sleeve for other downhole operations and the design parameters for the choke prevent the use of alignment lugs in axial slots. The mating profiles do not reduce the drift dimension through the sliding sleeve and allow higher housing pressure ratings for deep set applications with large operating differential pressures.

Abstract: A downhole closed-loop magnetostrictive sensor includes a magnetic field generating member and a waveguide operatively connected to the magnetic field generating member. At least one of the waveguide and the magnetic field generating member is responsive to a parameter being sensed. A sensor is operatively connected to the waveguide, and a housing includes a chamber enclosing the magnetic field generating member, the waveguide and the sensor. The housing is configured and disposed to withstand a downhole environment.

Abstract: A downhole closed-loop magnetostrictive sensor includes a magnetic field generating member and a waveguide operatively connected to the magnetic field generating member. At least one of the waveguide and the magnetic field generating member is responsive to a parameter being sensed. A sensor is operatively connected to the waveguide, and a housing includes a chamber enclosing the magnetic field generating member, the waveguide and the sensor. The housing is configured and disposed to withstand a downhole environment.

Abstract: A hydraulic system includes a chemical injection line and a plurality of tools in operable communication with the chemical injection line that are independently responsive to changes in pressure or flow through the chemical injection line and that are configured to control flow of wellbore fluids.

Abstract: An alignment device for a sliding sleeve in a housing in a tubular string features a patterned alignment ring that remains stationary. The sliding sleeve in one of its end positions has a mating profile such that profile misalignment results in profile alignment as the sliding sleeve is axially advanced toward the alignment ring. In a choke application the fully closed position of the choke brings the profiles together to induce relative rotation into an aligned configuration of the ports on the sliding sleeve with the ports on the surrounding housing. Misalignment can occur when tools are run through the sliding sleeve for other downhole operations and the design parameters for the choke prevent the use of alignment lugs in axial slots. The mating profiles do not reduce the drift dimension through the sliding sleeve and allow higher housing pressure ratings for deep set applications with large operating differential pressures.

Abstract: In one aspect, an apparatus for use in a wellbore is disclosed, including: an inlet; an outlet; and a variable flow restriction configured to provide a predetermined constant pressure drop between the inlet and the outlet in response to a range of inlet flow rates. In another aspect, a method for providing a fluid flow within a wellbore is disclosed, including: providing the fluid flow to an inlet; restricting the fluid flow to provide a predetermined constant pressure drop between the inlet and an outlet in response to a range of fluid flow rates; and providing the fluid flow to the wellbore from the outlet.

Abstract: Disclosed herein is a hydraulic system. The system includes a chemical injection line and a plurality of tools in operable communication with the chemical injection line that are independently responsive to changes in pressure or flow through the chemical injection line and that are configured to control flow of wellbore fluids.

Abstract: Embodiments of the present invention provide methods for manufacturing an even-wall rotor or stator that do not suffer from drawbacks of the prior art. Even-wall rotors or stators produced according to those methods are also provided. In one embodiment, a method for manufacturing a rotor or stator for use in a mud motor is provided. The method includes providing a vacuum chamber; providing a metal electrode at least partially disposed in the vacuum chamber; providing a mold disposed in the vacuum chamber; and melting a portion of the electrode with a direct current arc, the molten metal flowing into the mold ring.

Abstract: Some embodiments of the present invention generally provide an apparatus that may be used in a coiled tubing drillstring and that can switch between effectively straight drilling and curved drilling without halting drilling. Methods for steering a coiled tubing drillstring are also provided. In one embodiment, an apparatus for use in drilling a wellbore is provided. The apparatus includes a mud motor; a housing; an output shaft; and a clutch actuatable between two positions. The clutch is configured to rotationally couple the mud motor to the output shaft when the clutch is in a first position as a result of fluid being injected through the clutch at a first flow rate, and rotationally couple the output shaft to the housing when the clutch is in a second position as a result of fluid being injected through the clutch at a second flow rate.

Abstract: The present invention generally relates to an apparatus and method for use in a wellbore. In one aspect, a downhole tool for use in a wellbore is provided. The downhole tool includes a housing having a shaped inner bore, a first end and a second end. The downhole tool further includes a rotor having a plurality of extendable members, wherein the rotor is disposable in the shaped inner bore to form at least one chamber therebetween. Furthermore, the downhole tool includes a substantially axial fluid pathway through the chamber, wherein the fluid pathway includes at least one inlet proximate the first end and at least one outlet proximate the second end. In another aspect a downhole motor for use in a wellbore is provided. In yet another aspect, a method of rotating a downhole tool is provided.