Abstract: An antenna assembly includes a bobbin positionable about an outer surface of a tool mandrel, and a coil wrapped about an outer bobbin surface of the bobbin and extending longitudinally along at least a portion of the outer bobbin surface. A plurality of ferrites are positioned within a groove defined in the outer surface of the tool mandrel, and the plurality of ferrites extend circumferentially about the outer surface and interpose the tool mandrel and the coil.

Abstract: A resilient backup ring is shaped for insertion with a sealing ring into an annular groove in at least one of two close fitting members in order to limit extrusion of the sealing ring. The backup ring is split by a cut permitting the backup ring to be contracted in diameter for seating of the backup ring in the annular groove. The cut defines respective shapes in two ends of the backup ring that engage each other for latching the backup ring in a contracted diameter configuration. At least one of the two ends has a cavity for receiving a tool for applying force to move the two ends apart and unlatch the backup ring from the contracted diameter configuration and expand the diameter of the backup ring for removal of the sealing ring from the annular groove.

Abstract: An antenna assembly includes a bobbin that provides a cylindrical body that defines an outer radial surface, an inner radial surface, and a central axis. One or more channels are defined on the outer radial surface, and each channel provides a first sidewall, a second sidewall opposite the first sidewall, a floor, and a pocket jointly defined by the first sidewall and the floor. A coil including one or more wires is wrapped about the bobbin and received within the one or more channels.

Abstract: An antenna assembly for wellbore logging tools is provided. The antenna assembly includes a coil wrapped about an outer surface of a bobbin positioned within a saddle of a tool mandrel. The antenna assembly also includes an inner sleeve positioned on an outer surface of the tool mandrel within the saddle, the inner sleeve being interposed between the coil and the tool mandrel. The antenna assembly also includes a plurality of ferrite channels formed within a groove defined in an inner surface of the inner sleeve, in which the plurality of ferrite channels being laterally separated by a plurality of dividers formed in the groove. The antenna assembly also includes a plurality of ferrites disposed within respective ones of the plurality of ferrite channels.

Abstract: An antenna assembly includes a bobbin that provides a cylindrical body that defines an outer radial surface, an inner radial surface, and a central axis. One or more channels are defined on the outer radial surface, and each channel provides a first sidewall, a second sidewall opposite the first sidewall, a floor, and a pocket jointly defined by the first sidewall and the floor. A coil including one or more wires is wrapped about the bobbin and received within the one or more channels.

Abstract: A resilient backup ring is shaped for insertion with a sealing ring into an annular groove in at least one of two close fitting members in order to limit extrusion of the sealing ring. The backup ring is split by a cut permitting the backup ring to be contracted in diameter for seating of the backup ring in the annular groove. The cut defines respective shapes in two ends of the backup ring that engage each other for latching the backup ring in a contracted diameter configuration. At least one of the two ends has a cavity for receiving a tool for applying force to move the two ends apart and unlatch the backup ring from the contracted diameter configuration and expand the diameter of the backup ring for removal of the sealing ring from the annular groove.

Abstract: A collar-mountable antenna for transmitting and receiving signals in a downhole environment, in at least some embodiments, comprises a bobbin having an inner surface and an outer surface, each of the inner and outer surfaces defining multiple slots, conductive wire disposed within the multiple slots on the outer surface of the bobbin, and ferrite disposed within the multiple slots on the inner surface of the bobbin.

Abstract: An antenna assembly includes a bobbin that provides a cylindrical body that defines an outer radial surface, an inner radial surface, and a central axis. One or more channels are defined on the outer radial surface, and each channel provides a first sidewall, a second sidewall opposite the first sidewall, a floor, and a pocket jointly defined by the first sidewall and the floor. A coil including one or more wires is wrapped about the bobbin and received within the one or more channels.

Abstract: An antenna assembly for wellbore logging tools is provided. The antenna assembly includes a coil wrapped about an outer surface of a bobbin positioned within a saddle of a tool mandrel. The antenna assembly also includes an inner sleeve positioned on an outer surface of the tool mandrel within the saddle, the inner sleeve being interposed between the coil and the tool mandrel. The antenna assembly also includes a plurality of ferrite channels formed within a groove defined in an inner surface of the inner sleeve, in which the plurality of ferrite channels being laterally separated by a plurality of dividers formed in the groove. The antenna assembly also includes a plurality of ferrites disposed within respective ones of the plurality of ferrite channels.

Abstract: An antenna assembly includes a bobbin positionable about an outer surface of a tool mandrel, and a coil wrapped about an outer bobbin surface of the bobbin and extending longitudinally along at least a portion of the outer bobbin surface. A plurality of ferrites are positioned within a groove defined in the outer surface of the tool mandrel, and the plurality of ferrites extend circumferentially about the outer surface and interpose the tool mandrel and the coil.

Abstract: An antenna assembly includes a bobbin positionable about an outer surface of a tool mandrel and providing an outer bobbin surface. A coil is wrapped about and extends longitudinally along at least a portion of the outer bobbin surface. An inner sleeve interposes the bobbin and the tool mandrel and receives a plurality of ferrites that interpose the tool mandrel and the coil.

Abstract: An antenna assembly includes a bobbin that provides a cylindrical body that defines an outer radial surface, an inner radial surface, and a central axis. One or more channels are defined on the outer radial surface, and each channel provides a first sidewall, a second sidewall opposite the first sidewall, a floor, and a pocket jointly defined by the first sidewall and the floor. A coil including one or more wires is wrapped about the bobbin and received within the one or more channels.

Abstract: An antenna assembly includes a bobbin that provides a cylindrical body that defines an outer radial surface, an inner radial surface, and a central axis. One or more channels are defined on the outer radial surface, and each channel provides a first sidewall, a second sidewall opposite the first sidewall, a floor, and a pocket jointly defined by the first sidewall and the floor. A coil including one or more wires is wrapped about the bobbin and received within the one or more channels.

Abstract: An antenna assembly includes a bobbin positionable about an outer surface of a tool mandrel, and a coil wrapped about an outer bobbin surface of the bobbin and extending longitudinally along at least a portion of the outer bobbin surface. A plurality of ferrites are positioned within a groove defined in the outer surface of the tool mandrel, and the plurality of ferrites extend circumferentially about the outer surface and interpose the tool mandrel and the coil.

Abstract: A collar-mountable antenna for transmitting and receiving signals in a downhole environment, in at least some embodiments, comprises a bobbin having an inner surface and an outer surface, each of the inner and outer surfaces defining multiple slots, conductive wire disposed within the multiple slots on the outer surface of the bobbin, and ferrite disposed within the multiple slots on the inner surface of the bobbin.

Abstract: An antenna assembly includes a bobbin positionable about an outer surface of a tool mandrel, and a coil wrapped about an outer bobbin surface of the bobbin and extending longitudinally along at least a portion of the outer bobbin surface. A plurality of ferrites are positioned within a groove defined in the outer surface of the tool mandrel, and the plurality of ferrites extend circumferentially about the outer surface and interpose the tool mandrel and the coil.

Abstract: An antenna assembly includes a bobbin that provides a cylindrical body that defines an outer radial surface, an inner radial surface, and a central axis. One or more channels are defined on the outer radial surface, and each channel provides a first sidewall, a second sidewall opposite the first sidewall, a floor, and a pocket jointly defined by the first sidewall and the floor. A coil including one or more wires is wrapped about the bobbin and received within the one or more channels.

Abstract: An antenna assembly includes a bobbin positionable about an outer surface of a tool mandrel and providing an outer bobbin surface. A coil is wrapped about and extends longitudinally along at least a portion of the outer bobbin surface. An inner sleeve interposes the bobbin and the tool mandrel and receives a plurality of ferrites that interpose the tool mandrel and the coil.

Abstract: A device for cutting trenches in hard rock. A plurality of disc-like primary cutters are positioned on arms around a frame. The frame rotates about a central shaft and the center shaft is moved along horizontally in the direction the trench is to be cut. Between the primary cutters are reaming cutters. Each primary and each reaming cutter is provided with a plurality of spaced apart indentors secured to the external surface and each indentor has an end point and being adaptable to penetrate the rock face upon the application of working force a distance "P" and wherein the indentor end points are spaced a distance not greater then 7P apart.

Abstract: The method of implanting a geophone in the earth including the steps of drilling a borehole in the earth, pumping grout into the borehole, pumping a geophone down the interior of a cylindrical pipe positioned in the borehole, the end of the pipe being adjacent the desired point of implantation of the geophone, and pumping additional grout into the borehole to completely surround the geophone and allow the grout to solidify. In one embodiment, a tubular drill pipe having a severable drill bit at the lower end is first used to drill a borehole, after which the drill bit is hydraulically severed from the tubular drill pipe and the grout and the geophone are pumped down into the hole through the interior of the drill pipe.