Abstract: Aspects of the subject technology relate to a sensor for a downhole tool. The downhole tool can include a collar and a sensor. The sensor can be secured to the collar for measuring one or more operational characteristics of the downhole tool during operation of the downhole tool. The sensor can include a substrate. The sensor can also include a plurality of strain gauges disposed on the substrate. The plurality of strain gauges can be configured to measure axial strains and torsional strains on the collar for measuring the one or more operational characteristics of the downhole tool.

Abstract: An apparatus comprises a sub-section of a pulse power drilling assembly including a transformer encircling a center flow tube through which a drilling mud is to flow for drilling a borehole into a subsurface formation based on periodic pulses of electrical discharges from the pulse power drilling assembly. The transformer comprises at least one primary winding that encircles the center flow tube; a core that encircles the at least one primary winding, wherein the core comprises an electrically non-conductive material; and at least one secondary winding that encircles the core.

Abstract: A method includes directionally drilling, with a pulse power drill string, of a borehole into a subsurface formation using pulse power. The directionally drilling comprises generating, by an electrical source, an electrical energy and storing, by a primary capacitor, the electrical energy. The method includes periodically discharging the electrical energy from the primary capacitor to be received by a switching device having a number of outputs, wherein each output of the number of outputs is electrically coupled to an electrode of a number of electrodes positioned on an electrode assembly; and unevenly distributing, by the switching device, the electrical energy across the number of electrodes based on selecting a subset of the number of electrodes to receive the electrical energy to alter a direction of the drilling of the borehole based on emitting of the electrical energy by the selected subset of the number of electrodes into the subsurface formation.

Abstract: An apparatus comprises an electrode assembly positioned at a bottom end of a pulse power drill string to be positioned in a borehole formed in a subsurface formation. The electrode assembly comprises multiple electrodes, wherein at least a subset of the multiple electrodes is to periodically emit a pulse of an electrical discharge into the subsurface formation to drill the borehole. The electrode assembly comprises a controller configured to alter a direction of drilling of the borehole based on selection of the subset from the multiple electrodes, wherein an effective attribute of at least one electrode of the multiple electrodes is different than the effective attribute of other electrodes of the multiple electrodes, wherein the effective attribute comprises at least one of a shape and a size.

Abstract: A method for supplying, via an electrical interface, an output electrical power to an electrical load that is downhole in a borehole formed in a subsurface formation, includes generating mechanical energy from a flow of a fluid being delivered into the borehole; converting the mechanical energy into an input electrical power; storing the input electrical power into a primary capacitor, wherein the input electrical power has a variance that is greater than a variance threshold. The method includes performing the following operations while continuing to generate the mechanical energy generated from the flow of the fluid, in response to determining that at least one load criteria is satisfied, discharging the input electrical power from the primary capacitor to the electrical load to power a downhole operation by the electrical load.

Abstract: A method is to perform pulse power drilling of a borehole into a subsurface formation. The method comprises altering drilling the borehole, based on the pulse power drilling, in a direction that is off-center from a center of the borehole, wherein the altering of the drilling of the borehole in the direction that is off-center comprises articulating at least one element of a drill string having a drill bit; and periodically emitting a pulse of electrical discharge into the subsurface formation from at least one electrode of an electrode assembly that is part of the drill bit.

Abstract: An apparatus comprises a sub-section of a pulse power drilling assembly including a transformer encircling a center flow tube. The transformer comprises at least one primary winding that encircles the center flow tube and a core that encircles the at least one primary winding. The core comprises an insulative material and an electrically conductive material, wherein the insulative material is positioned relative to the electrically conductive material to create at least one break to prevent an electrical path for current within the electrically conductive material during operation of the transformer. The transformer comprises a secondary winding that encircles the core.

Abstract: An apparatus comprises a sub-section of a pulse power drilling assembly including a transformer encircling a center flow tube through which a drilling mud is to flow for drilling a borehole into a subsurface formation based on periodic pulses of electrical discharges from the pulse power drilling assembly. The transformer comprises at least one primary winding that encircles the center flow tube; a core that encircles the at least one primary winding, wherein the core comprises an electrically non-conductive material; and at least one secondary winding that encircles the core.

Abstract: An apparatus comprises a sub-section of a pulse power drilling assembly including a transformer encircling a center flow tube. The transformer comprises at least one primary winding that encircles the center flow tube and a core that encircles the at least one primary winding. The core comprises an insulative material and an electrically conductive material, wherein the insulative material is positioned relative to the electrically conductive material to create at least one break to prevent an electrical path for current within the electrically conductive material during operation of the transformer. The transformer comprises a secondary winding that encircles the core.

Abstract: A rotary steerable tool for directional drilling includes a tool body including a flowbore for flowing pressurized fluid therethrough and a plurality of extendable members movably coupled to the tool body for selectively engaging a borehole wall, each extendable member including a piston for moving the extendable member to an extended position. The tool further includes a pressurized fluid supply flow path to provide fluid pressure from the flowbore to the pistons, and a plurality of linear actuators, each independently actuatable to control fluid pressure from the pressurized fluid supply flow path to a respective piston.

Abstract: A rotary steerable tool for directional drilling includes a tool body including a flowbore for flowing pressurized fluid therethrough and a plurality of extendable members movably coupled to the tool body for selectively engaging a borehole wall, each extendable member including a piston for moving the extend-able member to an extended position. The tool further includes a pressurized fluid supply flow path to provide fluid pressure from the flowbore to the pistons, and a plurality of linear actuators, each independently actuatable to control fluid pressure from the pressurized fluid supply flow path to a respective piston.

Abstract: A ranging system includes a drill string comprising a bottom hole assembly (BHA). A plurality of ranging devices are positioned in a spaced-apart orientation on the drill string and are operable to provide a conducting contact with a formation. At least one insulator member is positioned on the drill string between the plurality of ranging devices and is operable to provide a non-conducting contact with the formation. During drilling operations, the plurality of ranging devices provide conducting contact with a formation while the at least one insulator member provides non-conducting contact with the formation so to enhancing ranging operations while drilling. A method of modeling and simulating drill string response is provided to identify locations along the drill string for positioning insulator members.

Abstract: The useful life of a downhole tool is improved through application of an ultrasonic impact treatment. In an example method, operational parameters of an ultrasonic impact treatment device are selected based upon the one or more physical characteristics of the downhole tool. The ultrasonic impact treatment device is configured to correspond to the selected operational parameters. A residual compressive stress layer is then induced along a surface of the downhole tool using the configured ultrasonic impact treatment device, thereby improving the useful life of the downhole tool.

Abstract: Nearby conductors such as pipes, well casing, etc., are detectable from within a borehole filled with an oil-based fluid. At least some method embodiments provide a current flow between axially-spaced conductive bridges on a drillstring. The current flow disperses into the surrounding formation and causes a secondary current flow in the nearby conductor. The magnetic field from the secondary current flow can be detected using one or more azimuthally-sensitive antennas. Direction and distance estimates are obtainable from the azimuthally-sensitive measurements, and can be used as the basis for steering the drillstring relative to the distant conductor. Possible techniques for providing current flow in the drillstring include imposing a voltage across an insulated gap or using a toroid around the drillstring to induce the current flow.

Abstract: A ranging system includes a drill string comprising a bottom hole assembly (BHA). A plurality of ranging devices are positioned in a spaced-apart orientation on the drill string and are operable to provide a conducting contact with a formation. At least one insulator member is positioned on the drill string between the plurality of ranging devices and is operable to provide a non-conducting contact with the formation. During drilling operations, the plurality of ranging devices provide conducting contact with a formation while the at least one insulator member provides non-conducting contact with the formation so to enhancing ranging operations while drilling. A method of modeling and simulating drill string response is provided to identify locations along the drill string for positioning insulator members.

Abstract: Nearby conductors such as pipes, well casing, etc., are detectable from within a borehole filled with an oil-based fluid. At least some method embodiments provide a current flow between axially-spaced conductive bridges on a drillstring. The current flow disperses into the surrounding formation and causes a secondary current flow in the nearby conductor. The magnetic field from the secondary current flow can be detected using one or more azimuthally-sensitive antennas. Direction and distance estimates are obtainable from the azimuthally-sensitive measurements, and can be used as the basis for steering the drillstring relative to the distant conductor. Possible techniques for providing current flow in the drillstring include imposing a voltage across an insulated gap or using a toroid around the drillstring to induce the current flow.