A push-the-bit rotary guiding device includes a mandrel having a central passage; a sleeve which is rotatably sleeved outside the mandrel; a plurality of swing ribs which are circumferentially arranged in an outer wall of the sleeve with an interval; an actuation mechanism, for controlling each swing rib to swing respectively; a plurality of detectors, which are circumferentially arranged in the outer wall of the sleeve with an interval, for detecting a distance to a well wall in real-time; and a controller, for determining whether the actuation mechanism is required to actuate the swing ribs to swing according to the detected distance. An application method of the push-the-bit rotary guiding device is provided. According to the push-the-bit rotary guiding device, through a real-time detection of the detectors, a well section having an expanded or reduced diameter is detected in time and guiding of the rotary guiding device herein is avoided.

An example apparatus for controlling the direction of drilling a borehole includes a housing and a radially offsetable drive shaft at least partially within the housing. The apparatus may further include one or more pusher extendable from the housing. The one or more pusher may be extendable in response to a radial offset in the offsetable drive shaft with respect to a longitudinal axis of the housing.

A directional drilling system comprises a driveshaft to couple to a drill string or a drill bit and an apparatus. The apparatus comprises an eccentric coupler disposed at the driveshaft and a coil coupled at one end to the eccentric coupler. In some embodiments, the coil comprises a fixed end and a rotating end. In response to a first transition temperature, the rotating end of the coil causes the eccentric coupler to rotate about the driveshaft, so as to move the driveshaft from a first orientation to a second orientation. Additional apparatus, methods, and systems are disclosed.

A method and apparatus are provided for securing a protective sleeve or wear sleeve to a rotary component which is rotatable relative to a rotary seal, such that the wear sleeve is in relatively rotating sealing engagement with the rotary seal. The wear sleeve is secured to the shaft by wedging a lock ring between the wear sleeve and the shaft. Wedging action of the lock ring can be effected by wedging formations, such as tapered surfaces, configured for causing wedging of the lock ring in response to operator-induced axial movement of the lock ring relative to the shaft and/or the wear sleeve. Wedging of the lock ring can be effected by co-operating screw threads on the lock ring and the wear sleeve, so that an operator can tighten the sleeve on the shaft by application of torque thereto.

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.

An example downhole motor may include a first housing and a second housing with first and second portions characterized by non-parallel longitudinal axes. The second housing may be rotatably coupled to the first housing, and the first portion of the second housing may be arranged in a fixed, non-parallel longitudinal orientation with the first housing. A drive shaft may be at least partially within the first housing, and the motor may further comprise a selectively engageable torque coupling between the drive shaft and the second housing, positioned within the first housing.

Downhole rotary steerable drill including a drilling shaft rotatably supported within a housing, the drilling shaft and housing each having a longitudinal axis. The drill can include a releasable locking mechanism for rotationally locking and releasing the drilling shaft relative to the housing, the releasable locking mechanism transitionable between locked and released configurations. The releasable locking mechanism includes a sliding plunger coupled to the housing by a coupling that permits longitudinal reciprocation of the sliding plunger relative to the housing and prevents rotation of the sliding plunger relative to the housing. The releasable locking mechanism can also include pressure-responsive piston that reciprocates between an unactuated configuration and actuated configuration in response to applied pressure from a pressuring pump.

A rotary steerable tool may include a tool body with an upper end and a lower end. Additionally, the tool body may include at least one steering assembly extending from the tool body and includes at least one steering actuator configured to extend beyond other portions of the steering assembly. Furthermore, at least one cutter may be disposed on the rotary steerable tool a distance from the at least one steering actuator.

A steering head for use with a casing, the steering head having a body with a first body end with a lead edge, a second body end with a rear edge, and a body surface extending from the lead edge to the rear edge, an outer tube with an internal side generally facing the body surface, the outer tube extending from the first body end to the second body end, and a steering flap disposed on an external side of the outer tube having a first flap face facing radially inwardly and a second flap face facing radially outwardly. A fluid dispenser is disposed in a void defined between the outer tube and the body.

An apparatus for drilling a borehole into an earth formation includes: a drill bit configured to be rotated to drill into the formation; a drill tubular coupled to the drill bit and configured to rotate the drill bit; a steering device coupled to the drill string and configured to impart a force on the drill string to control a direction of drilling; and a controller configured to communicate a control signal to the steering device. The control signal includes information for directing actuation of the steering device for steering the drill bit in an intended drilling direction. The controller is further configured to direct the steering device to provide a compensating force on the drill string that prevents or reduces an azimuthal deviation from the intended drilling direction due to drill bit walking.