Abstract: An implantable medical lead includes a lead body extending from a proximal end to a distal end. The lead body includes an inner insulation layer and an outer insulation layer. The lead further includes a sleeve mechanically supported by the lead body at the distal end of the lead body. The lead further includes an uninsulated conductor coil. The uninsulated conductor coil includes a first portion having a first inner diameter, and a second portion having a second inner diameter and extending distally from the outer insulation layer. The first portion is positioned between the inner insulation layer and the outer insulation layer. The second inner diameter is greater than the first inner diameter. An outer surface of the second portion is exposed.

Abstract: A downhole drilling tool, forming part of a subterranean drilling system, may include at least one plate secured to an exterior of an elongate body. Electronics may be disposed between the plate and the body to be protected by the plate while still readily accessible. A dynamic element may be radially extendable from the plate to engage an inner wall of a borehole being drilled. If this radially-extendable element becomes worn or damaged from this engagement, the plate may be replaced. More expensive components of the drilling tool may be contained within the elongate body, rather than the plate, thus reducing replacement frequency. Additionally, plates including unique features may be employed at different times without altering the underlying elongate body.

Abstract: A downhole drilling tool, forming part of a subterranean drilling system, may include at least one plate secured to an exterior of an elongate body. Electronics may be disposed between the plate and the body to be protected by the plate while still readily accessible. A dynamic element may be radially extendable from the plate to engage an inner wall of a borehole being drilled. If this radially-extendable element becomes worn or damaged from this engagement, the plate may be replaced. More expensive components of the drilling tool may be contained within the elongate body, rather than the plate, thus reducing replacement frequency. Additionally, plates including unique features may be employed at different times without altering the underlying elongate body.

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 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.

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. One or more nozzles may be configured to automatically regulate a nozzle diameter, and therefore the pressure drop across the nozzle. A surge protector may be connected to the generator.

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 valve includes an exterior body and an interior body. The exterior body includes an ultrahard material, at least one exterior inlet, at least one exterior outlet, and a chamber inside the exterior body and in fluid communication with the exterior inlet and the exterior outlet. The interior body is located in the chamber within the exterior body and is moveable relative to the exterior body from an open configuration to a closed configuration. The interior body includes an ultrahard material, at least one interior inlet, and at least one interior outlet.

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 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: 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. One or more nozzles may be configured to automatically regulate a nozzle diameter, and therefore the pressure drop across the nozzle. A surge protector may be connected to the generator.

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 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.

Abstract: A downhole drilling tool, forming part of a subterranean drilling system, may include at least one plate secured to an exterior of an elongate body. Electronics may be disposed between the plate and the body to be protected by the plate while still readily accessible. A dynamic element may be radially extendable from the plate to engage an inner wall of a borehole being drilled. If this radially-extendable element becomes worn or damaged from this engagement, the plate may be replaced. More expensive components of the drilling tool may be contained within the elongate body, rather than the plate, thus reducing replacement frequency. Additionally, plates including unique features may be employed at different times without altering the underlying elongate body.

Abstract: A bit used in a downhole environment has an active element that is movable relative to the bit. The bit is rotated in the downhole environment, and at least one downhole parameter is measured. The at least one downhole parameter is compared against a target parameter value, and when the at least one downhole parameter is beyond a threshold value of the target parameter value, the active element is selectively relative to the bit. Movement of the active element alters the proportion of the weight on the active element as compared to the other cutting structure of the bit. Changing the proportion of weight can be used to reduce the depth of cut of the cutting structure and to reduce or eliminate motor stall or stick-slip behavior.

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 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 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 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 valve includes an exterior body and an interior body. The exterior body includes an ultrahard material, at least one exterior inlet, at least one exterior outlet, and a chamber inside the exterior body and in fluid communication with the exterior inlet and the exterior outlet. The interior body is located in the chamber within the exterior body and is moveable relative to the exterior body from an open configuration to a closed configuration. The interior body includes an ultrahard material, at least one interior inlet, and at least one interior outlet.