Abstract: A method for determining a rate of penetration of a drill bit during an earth drilling operation may comprise first urging an element to extend out from a working face of the drill bit. As drilling progresses, this extended element may then be forced back into the drill bit by an internal surface of a borehole being formed. A rate at which the element retracts back into the working face may be measured to aid in estimating a rate of penetration of the drill bit into the earth.

Abstract: A downhole turbine assembly may comprise a tangential turbine disposed within a section of drill pipe. A portion of a fluid flowing through the drill pipe may be diverted to the tangential turbine generally perpendicular to the turbine's axis of rotation. After rotating the tangential turbine, the diverted portion may be discharged to an exterior of the drill pipe.

Abstract: A downhole transducer assembly capable of being safely operated at a variety of pressures and depths may include a turbine rotatable by a fluid pressure differential rotationally fixed to a rotor in a generator. To reduce the rotational speed of the turbine and rotor, a pressure regulator may limit a fluid pressure differential by controlling the volumetric flow. In other embodiments, one or more nozzles may be configured to automatically regulate a nozzle diameter, and therefore the pressure drop across the nozzle. In other embodiments, a surge protector may be connected to the generator.

Abstract: An underreamer for increasing a diameter of a wellbore. The underreamer may include a body having an axial bore extending at least partially therethrough. An electromagnetic activation system may be disposed at least partially within the bore of the body. A valve may be disposed within the bore of the body and coupled to the electromagnetic activation system. The valve may include a mobile element and a static element. The mobile element may be coupled to the electromagnetic activation system and move from a first position where the mobile element obstructs fluid flow through the valve to a second position where the mobile element permits fluid flow through the valve. A cutter block may be movably coupled to the body and move radially-outward as the mobile element moves from the first position to the second position.

Abstract: A tool, e.g. a downhole tool, utilizes at least one actuator which may be actuated rapidly between positions during operation of the tool. The actuator is moved via flow of an actuating fluid controlled by a main valve which, in turn, is controlled via a pilot valve. The pilot valve is operated to selectively control flow of the actuating fluid to the main valve so as to shift the main valve between desired operational positions.

Abstract: A system includes a turbine, a valve, and an electronics package. The turbine is configured to generate electricity from a fluid flow through the turbine and the electronics package is configured to selectively actuate the valve between an open configuration and a closed configuration.

Abstract: A downhole drilling apparatus, passing through a subterranean borehole, may mark an inner wall of the borehole with a marking element. A sensor, spaced axially from the marking element on the drilling apparatus, may subsequently sense the marking as it passes. A rate of penetration of the drilling apparatus may be calculated by dividing an axial distance, between the marking element and the sensor, by a time interval, between when the marking element marks the inner wall and when the marking is sensed by the sensor. Alternately, a second sensor, spaced axially from the first, may also sense the marking. A rate of penetration may then be calculated by dividing an axial distance, between the two sensors, by a time interval, between when the two sensors sense the marking.

Abstract: A drilling apparatus may alter a direction of travel of a drill bit as it forms a borehole in the earth by furnishing the borehole with a cross-sectional shape that urges the drill bit in a radial direction. Such a cross-sectional shape may comprise two circular arcs, one larger than the apparatus and one smaller. The apparatus may be urged away from the smaller circular arc and into the open space provided by the larger circular arc. Such an apparatus may comprise an axial body and a cutting element extendable in a single radial direction from an exterior of the axial body. Extension of the cutting element may allow it to engage and degrade an inner wall of the borehole. An abrasion-resistant gauge pad protruding from the exterior of the body may ride against the borehole wall and urge the body radially.

Abstract: A downhole drilling apparatus may comprise a rotatable body with various cutting elements connected thereto, some radially protruding therefrom, some radially extendable therefrom, and some revolvable relative thereto about a common axis. In operation, when the body is rotated, the radially protruding cutting elements may bore a generally cylindrical borehole. The radially extendable cutting elements may be extended during specific portions of the body's rotation to degrade certain areas of an inner wall of the borehole transforming it into a non-cylindrical borehole. At certain times, the revolvable cutting elements may be allowed to slide against the non-cylindrical inner wall while freely revolving to minimize disturbance to the borehole shape. At other times, revolution of these revolvable cutting elements may be restrained to ream the borehole back to a cylindrical shape.

Abstract: A downhole drilling apparatus may comprise a rotatable body with fixed cutting elements protruding from an exterior thereof. To form a subterranean borehole, the fixed cutting elements, spaced at a constant radius from a rotational axis of the body, may degrade an earthen formation as the body rotates. The body may also have a rotatable cutting element protruding from its exterior. To remove material from an interior wall of the borehole, the rotatable cutting element may be positioned in a first rotational orientation wherein it extends radially beyond the constant radius of the fixed cutting elements. An amount of material being removed may be altered by rotating the rotatable cutting element into a second rotational orientation wherein it remains radially within the constant radius.

Abstract: A drill bit may include a bit body and at least two cones assemblies including at least two drive cylinders having at least two cones. The at least two cone assemblies are mounted on the bit body. The drill bit may also include an indexing mechanism coupled to the bit body and configured to rotate and lock at least one drive cylinder. A method of operating the drill bit may include providing fluid to the drill bit, rotating the drill string to drill formation, moving the indexing mechanism an axial distance within a central chamber of the drill bit, rotating the at least two indexable structures as the indexing mechanism moves, and locking the at least two indexable structures.

Abstract: A mechanical bearing includes a hard bearing element and a support element affixed to the hard bearing element, with a joining element between the hard bearing element and the support element, the joining element being more flexible than the hard bearing element and the support element.

Abstract: Aspects of the disclosure can relate to an apparatus including a first member having a first bearing surface formed from a hard material (e.g., a diamond-based material, such as a polycrystalline diamond material), and a second member coupled to an input shaft to translate (e.g., rotate, slide, etc.) with respect to the first member. The second member has a second bearing surface formed from a hard material, and the second bearing surface is to bear against the first bearing surface. In embodiments of the disclosure, the first and second members can be for devices including, but not necessarily limited to: solenoids, generators and/or motors (e.g., out-runner radial flux generators, axial flux generators, radial flux generators/motors, roller vane motors, etc.), gearboxes, rotary data swivels, digital actuators, filters (e.g., inner rotating filters), valves (e.g., proportional valves), sensors (e.g., pressure differential sensors), and so forth.

Abstract: A piston's stroke length may be restricted by passing a rod through a through hole in the piston. The stroke length's boundaries may be defined by the points where an interior of the through hole contacts an exterior of the rod. Adjusting a position or orientation of the rod may alter this stroke length. If the rod comprises a noncylindrical external geometry, a radius thereof may vary along an axial length of the rod or around a circumference thereof. Adjustment of the rod, via axial translation or rotation for example, may change the position of contact between the rod and the through hole. Alternately, the through hole may comprise a unique geometry in which the rod may radially translate to adjust the piston's stroke length.

Abstract: A downhole drilling assembly may comprise a sub secured between a drill string and a drill bit. The sub may comprise a cavity with a chassis housed therein. The drill bit may also comprise a cavity with an extender housed therein. This extender may provide access for various types of communication to reach into the drill bit's cavity. Several pairs of interfacing exchange surfaces may allow for communication (e.g. passing electrical, hydraulic, optical or electromagnetic signals) between these various elements. One pair of interfacing exchange surfaces, between the drill string and the chassis, may allow for communication regardless of relative rotational orientation. Two other pairs of interfacing exchange surfaces, one between the chassis and the extender and another between the extender and the drill bit, may require a specific rotational orientation for communication.

Abstract: 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 a the first and second bearing and being configured to extend from an exterior of the housing in response to pressure communicated to the chamber.

Abstract: A steerable downhole tool may alter a direction of travel of a drilling operation while drilling into the earth. The tool may accomplish this by extending a rod from openings disposed in a side of the tool. The rod may slide within a cavity passing from one of the openings to another. The rod may degrade material from an internal surface of a borehole in which the tool is traveling, by engaging the surface with cutter elements exposed on opposing tips of the rod. The tool may also push off of the borehole wall opposite from the area of degradation.

Abstract: A drill bit assembly, of a type useful for forming a borehole in the earth, may comprise a chassis, separate from a drill bit, housed within a cavity of the drill bit. A drill string may be secured to the drill bit and retain the chassis within the cavity. This chassis may comprise two pairs of interfacing exchange surfaces, a first pair disposed between the chassis and the drill string and a second pair disposed between the chassis and the drill bit. Both of the first pair are annular in shape and fixed together independent of rotational orientation. The second pair are fixed together in a specific rotational orientation. These pairs of interfacing exchange surfaces may allow for various types of signals, such as electrical, hydraulic, optical or electromagnetic for example, to be exchanged and passed through the chassis or to electronics disposed on the chassis.

Abstract: A tool, e.g. a downhole tool, utilizes at least one actuator which may be actuated rapidly between positions during operation of the tool. The actuator is moved via flow of an actuating fluid controlled by a main valve which, in turn, is controlled via a pilot valve. The pilot valve is operated to selectively control flow of the actuating fluid to the main valve so as to shift the main valve between desired operational positions.

Abstract: A method for determining a rate of penetration of a drill bit during an earth drilling operation may comprise first urging an element to extend out from a working face of the drill bit. As drilling progresses, this extended element may then be forced back into the drill bit by an internal surface of a borehole being formed. A rate at which the element retracts back into the working face may be measured to aid in estimating a rate of penetration of the drill bit into the earth.