Composite cables suitable for use in conjunction with wellbore tools. One cable may include a polymer composite that includes dopants dispersed in a polymer matrix and continuous fibers extending along an axial length of the cable through the polymer matrix, wherein the cable is characterized by at least one of the following: (1) at least a portion of the cable having a density greater than about 2 g/cm.sup.3, wherein at least some of the dopants have a density of about 6 g/cm.sup.3 or greater, (2) at least a portion of the cable having a density less than about 2 g/cm.sup.3, wherein at least some of the dopants have a density of about 0.9 g/cm.sup.3 or less, (3) at least some of the dopants are ferromagnetic, or (4) at least some of the dopants are hydrogen getters.

A wireline system includes a control system, a downhole tool, and a wireline cable coupling the downhole tool and the control system. The wireline cable includes a plurality of conductors, which includes a core conductor and a concentric conductor disposed around the core conductor, wherein two of the plurality of conductors form a conductor pair, and wherein each of the plurality of conductors is configured to transmit power, data, or both, between the control system and the downhole tool. The wireline cable further includes one or more insulative layers, wherein at least one insulative layer is disposed between any two conductors.

A technique facilitates construction and operation of a power cable which may be used to supply power to an electric submersible pumping system downhole into a wellbore. The power cable comprises at least one electrical conductor. Each electrical conductor is insulated with an insulation layer and protected from deleterious fluids by a fluid barrier layer. Further protection is provided by a protective layer disposed around the fluid barrier layer. The protective layer is foamed to provide a cushion layer and to further protect components of the power cable. An armor layer may be disposed around the protective layer.

An apparatus includes a flat cable that comprises multiple conductors that are encased in the cable armor and positioned in a flat cable configuration such that a void area is defined between the multiple conductors. The flat cable includes a filler positioned at least partially in the void area.

A cable coater system for a downhole tool includes a cable coater. The cable coater may include a housing and one or more rollers that are coupled to the housing, wherein the one or more rollers are configured to rest on the downhole cable while guiding the cable through openings in the cable coater during wireline operations. The cable coater may remain on cable during all spooling (on and off) activities for the duration of operations and activated to coat the cable upon the final pull out of hole and prior to storage of the cable. The spooling in and out of the cable may further be automatically controlled by providing a positional indicator of the cable coater and thus where the cable is in three-dimensional space relative the spool.

An electric submersible pumping system cable is provided with a plurality of conductors. The electric submersible pumping system cable includes at least one central strength member which may be in the form of a central strength member bundle. The plurality of conductors may be in the form of a plurality of individually insulated conductors arranged about the central strength member. The electric submersible pumping system cable also may include a jacket layer disposed over the insulated conductors.

A hybrid cable applicable in oil wells is disclosed, comprising a FIMT, a conductor layer formed by continuous laser welding and cylindrically covered the outer surface of the FIMT, the outer cylindrical surface of the conductor layer being covered with a high temperature resistant insulating layer by a continuous extrusion method or by wrapped helically with insulating tapes around the outer surface of the conductor layer and the external steel tube cylindrically covered the outer surface of the insulating layer. The conductor layer is coaxial with the FIMT, the inner space of the hybrid cable to accommodating excess length of the optical fiber for thermal expansions or the tensile stress of the optical cable. The thickness of the insulating layer cylindrically covered the outer surface of the conductor layer can be increased, thereby improving the insulating property. A method of manufacturing such hybrid cable is disclosed.

A well logging assembly adapted to collect data from the well, comprises a downhole locomotive to move a downhole portion of the logging assembly into the well, a power conduit to supply power from the surface to the downhole portion and a data conduit to transmit data from the downhole portion to the surface. The power conduit comprises a single electrical conductor to send electrical current to the downhole portion from a power supply at the surface. The downhole portion comprises an electrical contact exposed to the well for transmission of the return path for the electrical current to the surface.

Systems and methods of the disclosed embodiments may include a coiled tubing locatable in a wellbore, a power and communications cable positioned along the coiled tubing. The power and communications cable may include an electromagnetic waveguide, an inner metallic tubular surrounding the electromagnetic waveguide, an electrically conductive material surrounding the inner metallic tubular, an electrically insulating material surrounding the electrically conductive material, and an outer metallic tubular resistant to corrosion and abrasion surrounding the electrically insulating layer. The example system may include an electrical device locatable in the wellbore and coupleable to the cable and a control unit coupleable to the cable and operable to supply power to and communicate with the electrical device via the power and communications cable.

The present disclosure describes a downwell pump three-phase power cable containing three power conductors each provided with at least one extruded polymeric insulating layer made of an insulating polymer selected from an ethylene copolymer or a fiuoropolymer, a metal tube in radial external position with respect to the insulating layer, and an extruded encapsulating layer embedding the three power conductors and made of fiuoropolymer.