Abstract: A drill bit assembly for measuring reservoir formation properties comprises a bit head and a pin body, and an electrically insulated gap joint between two conductive parts of the drill bit assembly. The bit head has a cutting end and an opposite connecting end with an engagement section. The pin body comprises a connecting end with an engagement section. The pin connecting end is connected to the bit head connecting end such that the engagement sections overlap. The electrically insulating gap joint can fill a gap between the bit head and pin body engagement sections such that the bit head and pin body are mechanically connected together at the connecting ends but electrically separated. Alternatively or additionally, the pin body can have two pieces which are separated by an electrically insulating gap joint.

Abstract: A drill bit assembly for measuring reservoir formation properties comprises a bit head and a pin body, and an electrically insulated gap joint between two conductive parts of the drill bit assembly. The electrically insulating gap joint can fill a gap between bit head and pin body engagement sections such that the bit head and pin body are mechanically connected together at connecting ends but electrically separated. Alternatively or additionally, the pin body can have two pieces which are separated by an electrically insulating gap joint. An electrical conductor is electrically connected at a first end to the bit head and is communicable at a second end with an alternating current signal to transmit an alternating current into the bit head, thereby inducing an electric current into a reservoir formation adjacent the bit head.

Abstract: Oilfield drilling utilizes downhole data transmitted to surface for formation evaluation and steering of directional wellbores. A leading technology in providing subsurface to surface communication is Electro-Magnetic (EM) Telemetry. This technology is typically employed with a downhole antenna concentric with the bore of an electrically insulating “gap sub” portion of the system. The antenna blocks the bore from further use to conduct other sensors or equipment through. One aspect of the invention is to integrate the antenna into the structure of the gap sub, thereby clearing the bore for conducting other tools through, and also protecting the antenna from the harsh drilling environment, including abrasion, erosion, shock, and vibration. Another aspect of this invention enables the antenna to serve a secondary function as an anti-rotation feature between the two halves of the gap sub.

Abstract: A spindle for a mud pulse telemetry tool includes a seal section having an outer surface for contacting a lip seal of a spindle housing in which the spindle is mounted; a top section attachable to at least part of a valve assembly for generating mud pulses; and a base section having a proximal end attachable to a drive motor for moving the spindle and a distal end attachable to the top section such that the annular seal is fixed between the top and base sections. The seal section can be made of a ceramic material such as yttrium-stabilized zirconia.

Abstract: A brush and brush housing arrangement for use with an electric brushed motor containing viscous fluid. The brush and brush housing arrangement comprises a brush housing and at least one brush. The at least one brush comprising a first end that is in contact with a rotating commutator of the motor when in use and an opposed second end. At least one open-faced channel in a surface of the brush extends from the first end to the second end. The open-faced channel provides an exit for entrained fluid from the brush and brush housing, minimizing or eliminating brush lift caused by fluid being forced between the rotating commutator and the brush. Additional pressure relief channels for allowing escape of entrained fluid may be located in the housing.

Abstract: A drill bit assembly for measuring reservoir formation properties comprises a bit head and a pin body, and an electrically insulated gap joint between two conductive parts of the drill bit assembly. The bit head has a cutting end and an opposite connecting end with an engagement section. The pin body comprises a connecting end with an engagement section. The pin connecting end is connected to the bit head connecting end such that the engagement sections overlap. The electrically insulating gap joint can fill a gap between the bit head and pin body engagement sections such that the bit head and pin body are mechanically connected together at the connecting ends but electrically separated. Alternatively or additionally, the pin body can have two pieces which are separated by an electrically insulating gap joint.

Abstract: A drill bit assembly has a bit head and a pin body. The bit head comprises a cutting end, an opposite connecting end with an engagement section, and a feature facing the connecting end. The pin body comprises a tubular body with an axial bore therethrough, a connecting end with an engagement section and a feature facing the connecting end. The drill bit assembly is manufactured by positioning the pin body connecting end with the bit head connecting end such that the pin body and bit head engagement sections overlap with a gap therebetween, and the pin body and bit head features are aligned; injecting a thermoplastic or other connecting material in liquid form between the bit head and pin body engagement sections and into the gap; and solidifying the thermoplastic or other connecting material such that the bit head and pin body are mechanically coupled together at their connecting ends and their features are securely aligned.

Abstract: A gap sub assembly can be used to form an electrical isolation in a drill string, across which a voltage is applied to generate a carrier signal for an electromagnetic (EM) telemetry system. The assembly comprises two conductive generally cylindrical components fashioned with a matching set of male and female rounded coarse threads, held such that a relatively uniform interstitial space is formed in the overlap space between them. The third component is a substantially dielectric electrical isolator component placed into the gap between the threads that effectively electrically isolates the two conductive components. Injecting the dielectric material under high pressure forms a tight bond resistant to the ingress of conductive drilling fluids (liquids, gases or foam), thus forming a high pressure insulating seal.

Abstract: An acoustic isolator for use with tubular assemblies such as drillpipe or production tubing comprising an acoustic wave transmitter, the acoustic isolator comprising, in series connection, an odd integer ?/4 multiple tuning bar of first acoustic impedance adjacent the acoustic wave transmitter, an odd integer ?/4 multiple reflector tube of second acoustic impedance, and a snubber of third acoustic impedance, wherein there is an acoustic impedance mismatch between the odd integer ?/4 multiple tuning bar and the odd integer ?/4 multiple reflector tube and an acoustic impedance mismatch between the odd integer ?/4 multiple reflector tube and snubber, such that a ‘down’ wave propagated toward the isolator is reflected back substantially in phase with an ‘up’ wave propagated from the acoustic wave source away from the isolator.

Abstract: A spindle for a mud pulse telemetry tool includes a seal section having an outer surface for contacting a lip seal of a spindle housing in which the spindle is mounted; a top section attachable to at least part of a valve assembly for generating mud pulses; and a base section having a proximal end attachable to a drive motor for moving the spindle and a distal end attachable to the top section such that the annular seal is fixed between the top and base sections. The seal section can be made of a ceramic material such as yttrium-stabilized zirconia.

Abstract: The present disclosure describes a spindle for a mud pulse telemetry tool. The spindle includes a seal section having an outer surface for contacting a lip seal of a spindle housing in which the spindle is mounted; a top section attachable to at least part of a valve assembly for generating mud pulses; and a base section having a proximal end attachable to a drive motor for moving the spindle and a distal end attachable to the top section such that the seal section is fixed between the top and base sections. The seal section can be made of a ceramic material such as yttrium-stabilized zirconia.

Abstract: Oilfield drilling utilizes downhole data transmitted to surface for formation evaluation and steering of directional wellbores. A leading technology in providing subsurface to surface communication is Electro-Magnetic (EM) Telemetry. This technology is typically employed with a downhole antenna concentric with the bore of an electrically insulating “gap sub” portion of the system. The antenna blocks the bore from further use to conduct other sensors or equipment through. One aspect of the invention is to integrate the antenna into the structure of the gap sub, thereby clearing the bore for conducting other tools through, and also protecting the antenna from the harsh drilling environment, including abrasion, erosion, shock, and vibration. Another aspect of this invention enables the antenna to serve a secondary function as an anti-rotation feature between the two halves of the gap sub.

Abstract: A brush and brush housing arrangement for use with an electric brushed motor containing viscous fluid. The brush and brush housing arrangement comprises a brush housing and at least one brush. The at least one brush comprising a first end that is in contact with a rotating commutator of the motor when in use and an opposed second end. At least one open-faced channel in a surface of the brush extends from the first end to the second end. The open-faced channel provides an exit for entrained fluid from the brush and brush housing, minimizing or eliminating brush lift caused by fluid being forced between the rotating commutator and the brush. Additional pressure relief channels for allowing escape of entrained fluid may be located in the housing.

Abstract: A gap sub assembly can be used to form an electrical isolation in a drill string, across which a voltage is applied to generate a carrier signal for an electromagnetic (EM) telemetry system. The assembly comprises two conductive generally cylindrical components fashioned with a matching set of male and female rounded coarse threads, held such that a relatively uniform interstitial space is formed in the overlap space between them. The third component is a substantially dielectric electrical isolator component placed into the gap between the threads that effectively electrically isolates the two conductive components. Injecting the dielectric material under high pressure forms a tight bond resistant to the ingress of conductive drilling fluids (liquids, gases or foam), thus forming a high pressure insulating seal.

Abstract: A gap sub assembly can be used to form an electrical isolation in a drill string, across which a voltage is applied to generate a carrier signal for an electromagnetic (EM) telemetry system. The assembly comprises two conductive generally cylindrical components fashioned with a matching set of male and female rounded coarse threads, held such that a relatively uniform interstitial space is formed in the overlap space between them. The third component is a substantially dielectric electrical isolator component placed into the gap between the threads that effectively electrically isolates the two conductive components. Injecting the dielectric material under high pressure forms a tight bond resistant to the ingress of conductive drilling fluids (liquids, gases or foam), thus forming a high pressure insulating seal.

Abstract: A shaft protection washer to protect a rotating shaft in a “measurement while drilling” (MWD) tool. Use of the shaft protection washer renders the rotating shaft less susceptible to erosion from the drilling fluid flowing between the rotating component and the stationary component.

Abstract: A direct current electric motor brush and brush housing arrangement which significantly reduces the effect of brush lift in a brushed motor containing viscous fluid. The brush housing enables viscous fluid to avoid momentum transfer into the brushes by providing two or more pressure relief channels that provide the fluid with direct radial exits along the direction of the brush, potentially reducing the brush lift due to the fluid being forced between a rotating commutator and its associated brushes. The pressure relief channels may be located in the housing immediately adjacent to the brush, being radially disposed to the leading face (or leading and trailing faces) of each brush, or in the leading face (or leading and trailing faces) of each brush itself, and may include additional channels in the housing near but not immediately adjacent the brushes.

Abstract: An acoustic isolator for use with tubular assemblies such as drillpipe or production tubing comprising an acoustic wave transmitter, the acoustic isolator comprising, in series connection, an odd integer ?/4 multiple tuning bar of first acoustic impedance adjacent the acoustic wave transmitter, an odd integer ?/4 multiple reflector tube of second acoustic impedance, and a snubber of third acoustic impedance, wherein there is an acoustic impedance mismatch between the odd integer ?/4 multiple tuning bar and the odd integer ?/4 multiple reflector tube and an acoustic impedance mismatch between the odd integer ?/4 multiple reflector tube and snubber, such that a ‘down’ wave propagated toward the isolator is reflected back substantially in phase with an ‘up’ wave propagated from the acoustic wave source away from the isolator.

Abstract: A gap sub assembly can be used to form an electrical isolation in a drill string, across which a voltage is applied to generate a carrier signal for an electromagnetic (EM) telemetry system. The assembly comprises two conductive generally cylindrical components fashioned with a matching set of male and female rounded coarse threads, held such that a relatively uniform interstitial space is formed in the overlap space between them. The third component is a substantially dielectric electrical isolator component placed into the gap between the threads that effectively electrically isolates the two conductive components. Injecting the dielectric material under high pressure forms a tight bond resistant to the ingress of conductive drilling fluids (liquids, gases or foam), thus forming a high pressure insulating seal.

Abstract: A shaft protection washer to protect a rotating shaft in a “measurement while drilling” (MWD) tool. Use of the shaft protection washer renders the rotating shaft less susceptible to erosion from the drilling fluid flowing between the rotating component and the stationary component.