A connecting structure for a drill collar of a logging while drilling instrument and drill collar sub male and female joints are provided. The connecting structure for a drill collar of a logging while drilling instrument includes a male connecting joint and a female connecting joint matched with each other. The male connecting joint and the female connecting joint are rotatable relative to each other. Electrical passages are respectively arranged in the male and female connecting joints. One of the male and female connecting joints is provided with a multi-core coaxial electrical male connector connected with the electrical passage, and the other is correspondingly provided with a multi-core coaxial electrical female connector connected with the electrical passage. The male connecting joint is coaxially nested in the female connecting joint. The multi-core coaxial electrical male connector is inserted into and fitted to the multi-core coaxial electrical female connector.

A downhole data transmission system comprising a composite polymeric annular block including a ferrite channel molded therein. The block being suitable for being housed within an annular groove or trough in the shoulder of a drill pipe. The annular block comprising a volume of sub-micron and micron elements of Fe and Mn. The ferrite channel defining an annular core region and an insulated helical coil laying within the core region. One end of the insulated helical coil passing through the ferrite channel and the annular block. A gasket molded into the block and extending from the block provides a sealed pathway for the end of the coil to exit the groove and connect to a cable; the other end of the coil being connected to ground. The annular block further includes a bumper protruding from its peripheral wall and a void opening within the annular block proximate the bumper.

An electromagnetic clearance joint and an assembly method thereof are provided, the joint includes a mandrel and a shell. An inner diameter of the shell is larger than an outer diameter of the mandrel, the mandrel includes a first structure part and a second structure part which are connected to each other, and the shell includes a third structure part and a fourth structure part which are connected to each other. A plurality of acting grooves are evenly and circumferentially distributed around the first structure part. An outer diameter of the first structure part is gradually reduced, a plurality of annular ridges are sequentially distributed axially on the outer surface of the second structure part and form the ridge structures, a plurality of grooves axially extending are arrayed circumferentially on the outer surface of the second ridge structure.

A subsea hydrocarbon flowline system (300) is disclosed. The flowline system has a hydrocarbon flowline (302); an electric trace heating system (304) arranged along at least a part-length of the flowline to control the temperature of hydrocarbon fluid flowing in the flowline; and a power input connector (Pin) configured for receiving electrical power from an electrical power providing system for powering the electric trace heating system. The electric trace heating system has a first three-phase trace heating cable (C′) and a second three-phase trace heating cable (C″), each trace heating cable extending between the power input connector and a cable termination (T′; T″) where phase conduits (L1′, L2′, L3′; L1″, L2″, L3″) of the trace heating cable are Y-connected and terminate in a neutral connection point (L.sub.N′; L.sub.N″). Further, the flowline system has a power output connector (Pout) for providing electrical power to a subsea hydrocarbon production system; a first electrical conduit (306′) extending between the neutral connection point of the cable termination of the first trace heating cable and the power output connector; and a second electrical conduit (306″) extending between the neutral connection point of the cable termination of the second trace heating cable and the power output connector, wherein the first and the second electrical conduits are electrically accessible at the power output connector for powering the subsea hydrocarbon production system.

A spoolable device including a first communication interface, a second communication interface, a power management module, a functional electrical module, and a junction joining each of the above elements together and creating a shared pressure chamber. A method for making a spoolable device comprising welding a functional electrical module to a first portion of a junction box, welding a first communication interface to the first portion of a junction box, welding a power management module to a second portion of a junction box, welding a second communication interface to the second portion of a junction box, and welding the first portion of a junction box to the second portion of the junction box to form a pressure chamber inside the first and second portions of the junction box.

A tool includes a device including a housing and a rotor, the rotor to rotate about a longitudinal axis, and an axial gap generator including a stator assembly positioned adjacent to the rotor. The axial gap generator generates a voltage signal as a function of a gap spacing between the stator assembly and the rotor, the gap spacing being parallel to the longitudinal axis.

Systems and methods are provided for a wet-mate connector assembly that can include a stiffening material and a dielectric grease retainer for preventing the extrusion of dielectric grease during a wet connect. The wet-mate connector assembly can include a male portion and a female portion that can receive the male portion to form an electrical connection with the male portion. The wet-mate connector assembly can also include a dielectric grease retainer that can be positioned near the male portion and the female portion for retaining dielectric grease extruded from a contact chamber when the female portion receives the male portion. The dielectric grease retainer can seal and insulate the contact chamber. The contact chamber can be defined by an outer diameter of the male portion and an inner diameter of the female portion. The male portion and the female portion can include a stiffening material and an insulating material.

An apparatus for communicating a signal to or from a downhole tool includes a drill pipe configured to be rotated to drill a borehole, a tubular under axial tension and secured in the drill pipe, and a retention device secured to the tubular and configured to maintain the tubular under the axial tension. The retention device includes a portion extending from a body of the device in a direction that is non-inward-radial with respect to a longitudinal axis of the drill pipe. The apparatus further includes a transmission line disposed in the tubular and in an opening of the retention device and in communication with the downhole tool.

A pressure-blocking feedthru that is exposable to varying temperatures and pressures includes various components. For example, the pressure-blocking feedthru might include pressure-blocking assemblies that each include a respective pressure-barrier shell and insulated pin assembly. The pressure-blocking feedthru also includes an interface assembly that couples the pressure-blocking assemblies to one another. The interface assembly includes a double-ended socket for coupling the insulated pin assemblies and a sleeve that circumscribes the doubled ended socket and at least part of the first and the second ceramic pin assemblies. In addition, the pressure-blocking assemblies might each be connected to a cable-connection assembly that employs a pressure-balanced cable termination.

Systems including wellbore tubing having an anchor assembly, an upper control line connector coupled to the anchor assembly, a first housing, and a first connector. The first connector provides a first angular mating face that faces tangentially with respect to the first housing, an upper control line operatively coupled to the first housing, and first communication media that extend through the first housing to the first angular mating face. A completion assembly within a wellbore has a completion receptacle to receive the anchor assembly, a lower control line connector coupled to the completion receptacle and a second housing and a second connector. The second connector provides a second angular mating face that faces tangentially with respect to the second housing, and a lower control line operatively coupled to the second housing and one or more second communication media that extend through the second housing to the second angular mating face.