Drilling system, biasing mechanism and method for directionally drilling a borehole
AssigneeB&W Mud Motors, LLC
InventorsStuart Schaaf, Marcus D. Wernig
Life of this patent
Estimating the term…
Abstract
A variable offset bearing assembly, associated with an offset shaft, having a longitudinal axis, disposed with a housing, having a longitudinal axis, the assembly including a radial bearing associated with the offset shaft; a thrust bearing associated with the offset shaft; the radial bearing and thrust bearing permit axial misalignment between the longitudinal axes of the offset shaft and the housing; and the thrust bearing and radial bearing manage axial and radial misalignment of the radial bearing and thrust bearing within the housing, caused by an axial or radial force exerted upon the housing and offset shaft.
Claims8
A method for directionally drilling a portion of a borehole, comprising:
- utilizing a drilling system associated with a drill string, the drilling system, including:
- a bearing section having a housing having a lower end, a longitudinal axis, and an upper bearing assembly and a lower bearing assembly disposed within the housing;
- an offset shaft, having a lower end and a longitudinal axis, independently rotatable within the housing and a drill bit associated with the lower end of the offset shaft;
- and the upper and lower bearing assemblies each including a radial bearing and a thrust bearing and provide a variable offset bearing assembly;
- moving the drill string until the drill bit of the drilling system contacts a bottom of the borehole;
- rotating the offset shaft and drill bit with respect to the housing, while not rotating the drill string and the housing, to drill the portion of the borehole;
- and
- while the drill bit is in the borehole drilling the portion of the borehole, permitting axial misalignment between the longitudinal axes of the offset shaft and the housing and managing axial and radial misalignment of the radial and thrust bearings within the housing caused by an axial or a radial force exerted upon the housing and offset shaft.
A method for directionally drilling a portion of a borehole, comprising:
- utilizing a drilling system associated with a drill string, the drilling system, including:
- a bearing section having a housing having a lower end, a longitudinal axis, and an upper bearing assembly and a lower bearing assembly disposed within the housing;
- an offset shaft, having a lower end and a longitudinal axis, independently rotatable within the housing and a drill bit associated with the lower end of the offset shaft;
- and a biasing mechanism associated with the upper bearing assembly in the bearing section;
- moving the drill string until the drill bit of the drilling system contacts a bottom of the borehole;
- rotating the offset shaft and drill bit with respect to the housing, while not rotating the drill string and the housing, to drill the portion of the borehole;
- and
- while the drill bit is in the borehole drilling the portion of the borehole, operating the biasing mechanism to actively manage an angular relationship between the longitudinal axes of the housing and the offset shaft.
Dependencies are inferred from the claim text.