Abstract: An apparatus disposed on a drillstring deviates a borehole advanced by a drill bit. At least one director is disposed on a housing to rotate therewith. The director at least includes a piston movable in a chamber, a pad pivotable about a pivot point between an extended condition and a retracted condition relative to the housing, and a linkage arm pivotably connected between the piston and the pad. At least one actuator disposed on the housing in fluid communication with a housing bore is operable at least between a first condition (directing communicated fluid from the bore or other source to the chamber of the director) and a second condition (at least permitting the director to retract toward the retracted condition).

Abstract: A rotary steerable tool used for directional drilling include a housing, at least one external director, and at least one valve. The external director is hydraulically movable to an extended condition relative to the housing, and the valve selectively directs pressurized fluid from a first side of the valve to the external director on the valve's second side. A first seal of the valve is selectively orientable about an axis and has an inlet, which communicates with the pressurized fluid from the first side. A second seal of the valve disposed adjacent the first seal has an outlet, which communicates the pressurized fluid to the second side at least when aligned with the inlet. A bearing assembly of the valve is disposed at the axis between the seals and has male and female bearing surfaces, which are angled off the axis and are mated with one another.

Abstract: A rotary steerable tool used for directional drilling include a housing, at least one external director, and at least one valve. The external director is hydraulically movable to an extended condition relative to the housing, and the valve selectively directs pressurized fluid from a first side of the valve to the external director on the valve's second side. A first seal of the valve is selectively orientable about an axis and has an inlet, which communicates with the pressurized fluid from the first side. A second seal of the valve disposed adjacent the first seal has an outlet, which communicates the pressurized fluid to the second side at least when aligned with the inlet. A bearing assembly of the valve is disposed at the axis between the seals and has male and female bearing surfaces, which are angled off the axis and are mated with one another.

Abstract: An apparatus is disposed on a drillstring for deviating a borehole advanced by a drill bit. The assembly includes a housing, at least one director, and at least one actuator. The housing is disposed on the drillstring and transfers rotation to the drill bit. The housing has a bore communicating fluid from the drillstring to the drill bit. The at least one director is disposed on the housing to rotate therewith. The at least one director at least includes a piston movable in a chamber, a pad pivotable about a pivot point between an extended condition and a retracted condition relative to the housing, and a linkage arm pivotably connected between the piston and the pad. The at least one actuator is disposed on the housing in fluid communication with the bore.