Abstract: The present disclosure includes a plug for cementing a wellbore. The plug may include a cylinder. The cylinder may include at least one body including a non-conductive material with conductive filaments dispersed within the non-conductive material. The present disclosure also includes float equipment for cementing a wellbore. The float equipment may include a casing segment including an inner surface, drillable material affixed to the inner surface of the casing segment, and a check valve attached to the drillable material. The drillable material may include a non-conductive material and conductive filaments dispersed within the non-conductive material.

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 downhole drilling system is disclosed. The downhole drilling system may include a drill bit including a first electrode and a second electrode. The downhole drilling system may also include a pulse-generating circuit coupled to the first electrode and the second electrode. A capacitor within the pulse-generating circuit may include a plurality of electrode sheets and a plurality of dielectric sheets interleaved with the plurality of electrode sheets. Each of the dielectric sheets may include a composite material including a polymer matrix formed from a polymer component and a nanoparticle component that increases the dielectric constant of the composite material above that of the polymer component.

Abstract: The present invention relates to HPMA-CBz copolymers and methods for treating certain diseases comprising administering the copolymers to a subject in need thereof.

Abstract: A electrocrushing drill bit may include a bit body; an electrode coupled to a power source and the bit body, the electrode having a distal portion for engaging with a surface of a wellbore; a ground ring coupled to the bit body proximate to the electrode and having a distal portion for engaging with the surface of the wellbore, the electrode and the ground ring positioned in relation to each other such that an electric field produced by a voltage applied between the ground ring and the electrode is enhanced at a portion of the electrode proximate to the distal portion of the electrode and at a portion of the ground ring proximate to the distal portion of the ground ring; and an insulator coupled to the bit body between the electrode and the ground ring.

Abstract: A disclosed pulsed-power drilling system may include a controller that receives and analyzes feedback from downhole components reflecting changing conditions or performance measurements associated with a pulsed drilling operation to determine that an operating parameter of the drilling operation should be modified. The controller may output a control signal to cause an adjustment of a configurable downhole component, such as mechanical, electrical, or hydraulic component that affects the operating parameter, while the drill bit remains in the wellbore. The controller may adjust a segmented transformer of a pulse-generating circuit, changing the number of primary winding switches that are fired, or the timing of the firing of the switches, to modify characteristics of the generated pulses. Adjusting a downhole component may affect the drilling rate, the drilling direction, the flow of drilling fluid, a pulse rise time, a pulse repetition rate, or a rate of penetration for the drilling operation.

Abstract: A disclosed pulsed-power drilling system may include a controller that receives and analyzes feedback from downhole components reflecting changing conditions or performance measurements associated with a pulsed drilling operation to determine that an operating parameter of the drilling operation should be modified. The controller may output a control signal to cause an adjustment of a configurable downhole component, such as mechanical, electrical, or hydraulic component that affects the operating parameter, while the drill bit remains in the wellbore. The controller may adjust a segmented transformer of a pulse-generating circuit, changing the number of primary winding switches that are fired, or the timing of the firing of the switches, to modify characteristics of the generated pulses. Adjusting a downhole component may affect the drilling rate, the drilling direction, the flow of drilling fluid, a pulse rise time, a pulse repetition rate, or a rate of penetration for the drilling operation.

Abstract: A electrocrushing drill bit may include a bit body; an electrode coupled to a power source and the bit body, the electrode having a distal portion for engaging with a surface of a wellbore; a ground ring coupled to the bit body proximate to the electrode and having a distal portion for engaging with the surface of the wellbore, the electrode and the ground ring positioned in relation to each other such that an electric field produced by a voltage applied between the ground ring and the electrode is enhanced at a portion of the electrode proximate to the distal portion of the electrode and at a portion of the ground ring proximate to the distal portion of the ground ring; and an insulator coupled to the bit body between the electrode and the ground ring.

Abstract: A downhole drilling system is disclosed. The downhole drilling system may include a drill bit including a first electrode and a second electrode. The downhole drilling system may also include a pulse-generating circuit coupled to the first electrode and the second electrode. A capacitor within the pulse-generating circuit may include a plurality of electrode sheets and a plurality of dielectric sheets interleaved with the plurality of electrode sheets. Each of the dielectric sheets may include a composite material including a polymer matrix formed from a polymer component and a nanoparticle component that increases the dielectric constant of the composite material above that of the polymer component.

Abstract: A downhole drilling system is disclosed. The downhole drilling system may include a pulse-generating circuit electrically coupled to a power source configured to provide an alternating current at a frequency and an input voltage, the pulse-generating circuit comprising an input stage circuit electrically coupled to the power source, the input stage circuit configured to control the alternating current in the pulse-generating circuit; a transformer circuit electrically coupled to the input stage circuit, the transformer circuit comprising an open-core transformer configured to generate an output voltage higher than the input voltage; and an output stage circuit electrically coupled to the transformer circuit, the output stage circuit configured to store energy for an electric pulse; and a drill bit including a first electrode and a second electrode electrically coupled to the output stage circuit to receive the electric pulse from the pulse-generating circuit.

Abstract: A downhole drilling system is disclosed. The downhole drilling system may include a pulse-generating circuit electrically coupled to a power source to provide power at a frequency, the pulse-generating circuit comprising an input stage tank circuit electrically coupled to the power source, the input stage tank circuit configured to have a resonant frequency approximately equal to the frequency; a series tank circuit electromagnetically coupled to the input stage tank circuit, the series tank circuit configured to have a resonant frequency approximately equal to the frequency; and an output stage tank circuit electromagnetically coupled to the series tank circuit, the output stage tank circuit configured to have a resonant frequency approximately equal to the frequency; and a drill bit including a first electrode and a second electrode electrically coupled to the output stage tank circuit to receive an electric pulse from the pulse-generating circuit.

Abstract: Electrocrushing drills and methods for operating electrocrushing drills. Electrocrushing drill bits comprise one or more high voltage electrodes surrounded by a ground or current return structure, which can be a ring or a comprise rod shaped electrodes. Openings in the rim of the current return structure facilitate removal of drilling debris and bubbles created by the electrocrushing process out from the bottom face of the bit and up the wellbore. The high voltage electrodes can be arranged in a circle. The current return structure may partially cover the bottom face of the drill bit, thereby enclosing the high voltage electrodes in openings that may be sector shaped. The drill may comprise one or more conducting loops, in each of which pulsed current creates a pulsed magnetic field. The loops can be oriented in particular directions to provide a pulsed magnetic field with the desired configuration and orientation in space. The formation ahead of the drill can then be evaluated with the appropriate sensors.

Abstract: A drill bit for downhole electrocrushing drilling is disclosed. A electrocrushing drill bit may include a bit body; an electrode coupled to a power source and the bit body, the electrode having a distal portion for engaging with a surface of a wellbore; a ground ring coupled to the bit body proximate to the electrode and having a distal portion for engaging with the surface of the wellbore, the electrode and the ground ring positioned in relation to each other such that an electric field produced by a voltage applied between the ground ring and the electrode is enhanced at a portion of the electrode proximate to the distal portion of the electrode and at a portion of the ground ring proximate to the distal portion of the ground ring; and an insulator coupled to the bit body between the electrode and the ground ring.

Abstract: Method and apparatus for isolating and switching lower voltage pulses from high voltage pulses in electrocrushing and electrohydraulic drills. A transformer with a high permeability core acts as a magnetic switch or saturating inductor to switch high voltage pulses to initiate an electrocrushing arc and lower voltage pulses to sustain the arc. The transformer isolates the lower voltage components from the high voltage pulses, and switches to deliver the low voltage current when the core saturates. The transformer enables impedance matching to the arc during all stages of drilling. The saturation time of the transformer core is the time delay between initiation of delivering the high voltage pulse and initiation of delivering the lower voltage current.

Abstract: Electrocrushing drill bits comprising one or more high voltage electrodes surrounded by a ground or current return structure, which can be a ring or a comprise rod shaped (i.e. cylindrical) electrodes. Openings in the rim of the current return structure facilitate removal of drilling debris and bubbles created by the electrocrushing process out from the bottom face of the bit and up the wellbore. The high voltage electrodes can be arranged in a circle. The current return structure may partially cover the bottom face of the drill bit, thereby enclosing the high voltage electrodes in openings that may be sector shaped. Also a method and apparatus for dividing a flow of drilling fluid both to sweep drilling debris and bubbles out of the drill bit and hole and to cool high power electrical components.

Abstract: A downhole drilling system is disclosed. The downhole drilling system may include a drill bit including a first electrode and a second electrode. The downhole drilling system may also include a pulse-generating circuit coupled to the first electrode and the second electrode. A capacitor within the pulse-generating circuit may include a plurality of electrode sheets and a plurality of dielectric sheets interleaved with the plurality of electrode sheets. Each of the dielectric sheets may include a composite material including a polymer matrix formed from a polymer component and a nanoparticle component that increases the dielectric constant of the composite material above that of the polymer component.

Abstract: A method and apparatus for breaking mineral particles comprising suspending the particles in a liquid flowing in a conduction path, the liquid comprising a dielectric constant higher than the particles and wherein an electric voltage pulse is sent to electrodes to pass an electric field in the mineral particles with sufficient stress to fracture the mineral particles.

Abstract: The present invention provides for an electrically insulating fluid or material of high relative permittivity or dielectric constant. The fluid has a low conductivity and high relative strength and is applicable to pulsed power drilling applications.

Abstract: An apparatus and method for controlling power delivered to a pulsed power system which includes a command charge switch for controlling when power produced by a primary power system is fed into a cable. The command charge switch also controls the power delivered to the pulsed power system in a bottom hole assembly.

Abstract: The present invention provides for an assembly for creating a pressure pulse in a liquid-filled cavity within a fracturable material such as a boulder wherein the primary energy storage element is disposed in a transducer at the boulder to improve the coupling of energy between the energy storage unit and the fluid in the boulder.