A downhole steering system includes a substantially tubular housing, a shaft positioned within the substantially tubular housing, a first bearing and a second bearing, the first and second bearings being configured to support rotation of the shaft relative to the housing. The first bearing, the second bearing, the shaft, and the housing at least partially define a chamber therebetween. The system also includes at least one structure positioned axially between the first and second bearing and being configured to extend from an exterior of the housing in response to pressure communicated to the chamber.

The present application discloses a push type rotary guide drilling system. The push type rotary guide drilling system includes: a drill bit and a rotating shaft, the rotating shaft including an upper rotating shaft and a lower rotating shaft; a steering portion, sleeving an outer side of the rotating shaft; a push assembly, including a plurality of push pieces spaced along a circumferential direction of the steering portion; a transmission device, including a transmission mechanism for driving the push pieces to extend out of the steering portion, the transmission mechanism including a driving electromagnetic gear arranged on the upper rotating shaft and a driven electromagnetic gear arranged on the steering portion and further including a motion conversion unit converting rotary motion of the driven electromagnetic gear into linear motion of the push pieces; and a control unit, configured to modulate a magnetic field to make the driving electromagnetic gear and the driven electromagnetic gear realize linkage through magnetic coupling and make the driving electromagnetic gear and the driven electromagnetic gear operate in an adjustable transmission ratio. According to the system in the present application, it is unnecessary for the steering portion to be provided with a circuit component, a conductive socket and the like, thereby simplifying a structure of the steering portion, effectively shortening a size of the steering portion, improving the flexibility of underground feed motion and reducing cost.

System and methods for using channel quality reports to reduce inter-band interference are disclosed. Channel information is received at a first wireless communication device from a second wireless communication device. The first wireless device is operating in a first frequency range, and the second wireless device is operating in a second frequency range. The first frequency range is adjacent to the second frequency range. A channel quality report is generated at the first wireless communication device. The channel quality report indicates that particular sub-bands in the first frequency range have low channel quality. The particular sub-bands are selected using the channel information.

An apparatus for use in a wellbore includes a non-rotating section disposed along the drill string. The non-rotating section has a bore and at least one biasing member engaging an adjacent wall. A rotating section is disposed in the bore of the non-rotating section and a bearing is positioned between the rotating section and the non-rotating section. The apparatus also includes a relative rotation sensor that generates signals representative of a rotation of the rotating section relative to the non-rotating section, an orientation sensor that generates signals representative of an orientation of the non-rotating section relative to a selected frame of reference, and a controller in signal communication with the at least one relative rotation sensor and the at least one orientation sensor. The controller adjusts a force applied by the at least one biasing element, and/or a position of the at least one biasing element in response to the generated signals from the at least one relative rotation sensor and the generated signals from the at least one orientation sensor.

A hybrid Rotary Steerable System (RSS) includes both exterior steering pads as in a push-the-bit system and, internal shaft pistons as in a point-the-bit system. The steering pads and the shaft pistons may cooperate to permit the RSS to achieve tighter turning radii. The steering pads and the shaft pistons may be independently or collectively controllable by diverting a portion of drilling fluid flowing through the RSS. In some embodiments, the steering pads and shaft pistons may extend in opposite directions to steer the drill bit, and on other embodiments, the steering pads and shaft pistons may extend in the same direction.

A seal assembly in an apparatus including a housing, a housing bore defined by the housing, a shaft extending through the housing bore, and a shaft bore defined by the shaft. The housing bore includes an annular seal chamber between the housing and the shaft. The seal assembly includes a flexible tubular seal surrounding the shaft within the seal chamber. The tubular seal has a shaft end sealingly connected with the shaft and a housing end sealingly connected with the housing. The tubular seal divides the seal chamber into an interior seal chamber which is sealed from an exterior of the housing and an exterior seal chamber which is sealed from an interior space of the housing. At least one seal pressure balancing port is defined by the shaft and extends between the shaft bore and the exterior seal chamber.

A drill string steering system includes a flow manifold and a rotary valve. An actuation flow channel and a backflow channel are rotatable with respect to piston flow channels of the flow manifold. The actuation flow channel is rotatable relative to the flow manifold to increase or decrease flow toward the piston for controlling actuation of the piston. The backflow channel is rotatable relative to the flow manifold to increase or decrease flow away from the piston to the annulus for controlling retraction of the piston.

A mechanical rotary steering drilling tool for steering a drill string includes a test section, a clutch device, a control mechanism, and an execution part. The test section is used as an upper joint in cooperation with the tool. The clutch device is externally connected with a guide body and internally coupled with a mandrel. A groove on a cylindrical surface of a switch control cylinder is matched with a control screw to determine rotation of a fluid channel switch. A pushing block of the execution part extends out against a wellbore wall to push a drill bit for steering drilling after the fluid channel is opened.

The disclosed embodiments relate to a rotary steering having a plurality of hydraulically actuated steering pad assemblies and a valve positioned between a primary flow channel of the rotary steering tool and an actuating piston of each of the plurality of steering pad assemblies. The representative valve includes a two-disk valve, with an uphole disk having a single, fixed-area aperture and a downhole disk having a plurality of independently variable-area orifices. Each of the independently variable valve orifices corresponds to one of a plurality of valve ports. In turn, each valve port being is fluidly coupled to, and operable to actuate, a corresponding piston of one of the plurality of steering pad assemblies. The independently variable-area orifices can be manipulated (gradually opened or closed) to vary the pressure drop across the tool, and thereby vary the magnitude of hydraulic force available to actuate the steering pad assemblies.

A rotary tool for operation within an underground borehole or within tubing in a borehole has a tool body and at least one sensor-containing unit attached to the tool body and positioned to contact the conduit wall. The sensor-containing unit includes an exterior portion to contact the borehole or tubing wall and one or more sensors is located in a cavity between the exterior portion and the tool body. The sensor-containing unit may be formed from the exterior portion, an attachment portion for attachment to the tool body, and one or more connecting portions extending between the attachment and exterior portions, with the sensor-containing cavity between the attachment and exterior portions. Possible rotary tools include drill bits, reamers, mills, stabilizers, and rotary steerable systems.