Drilling assembly having a tilted or offset driveshaft
AssigneeHalliburton Energy Services, Inc.
InventorsJohn Keith Savage, Stephen Jones
Life of this patent
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Abstract
A drilling assembly includes a straight housing in which a mud motor assembly is mounted. The mud motor includes a rotor that rotates within a stator. The rotor has an axial centerline substantially parallel with the housing. A drivetrain is coupled between the rotor and a driveshaft. The driveshaft is coupled to a drill head. The driveshaft has a centerline that is non-coincident with (i.e., offset or angled) the axial centerline. The angle between the driveshaft centerline and the axial centerline may be fixed or variable. The angle may be variable in response to an axial force, imparted to the rotor, that is transferred to the driveshaft through the drivetrain. Additional apparatus, systems, and methods are disclosed.
Claims19
A drilling assembly, comprising:
- a motor assembly coupled to a non-bent housing and having an axial centerline;
- a drivetrain located within the housing and coupled to the motor assembly;
- a drill head;
- a driveshaft located within and extending from the housing and coupled between the drivetrain and the drill head, the driveshaft having a centerline at an angle with the axial centerline;
- and
- wherein the angle is variable in response to a change in an axially aligned force, the axially aligned force due to a pressure differential across the motor assembly.
A drilling system comprising:
- a downhole tool comprising:
- a non-bent housing;
- a motor assembly coupled to the housing and having an axial centerline, the motor assembly comprising a rotor and a stator;
- a driveshaft coupled to the rotor and located within and extending from the housing, the driveshaft having a centerline at an angle with the axial centerline, wherein the angle is variable in response to a change in an axially aligned force, the axially aligned force due to a pressure differential across the motor assembly;
- and
- a drill head coupled to the driveshaft.
A downhole tool comprising:
- a non-bent housing;
- a motor assembly coupled to the housing and having an axial centerline, the motor assembly comprising a rotor and a stator;
- a driveshaft coupled to the rotor and located within and extending from the housing, the driveshaft having a centerline at an angle with the axial centerline, wherein the angle is variable in response to a change in an axially aligned force, the axially aligned force due to a pressure differential across the motor assembly;
- a piston shaped to interact with a flow of fluid to exaggerate the axially aligned force;
- and
- a drill head coupled to the driveshaft.
Dependencies are inferred from the claim text.