A fire resistant coaxial cable and method of making includes a 2-part dielectric made of a polymer foam and a ceramifiable silicone rubber. The polymer foam, which can be polypropylene or other polymers, leaves little-to-no residue in the cable that causes electromagnetic loss when upon burning. The polymer foam can be extruded over a center conductor using an inert gas, such as nitrogen, to propagate the foam, ensuring little-to-no residue in the cable. The ceramifiable silicone rubber can be extruded over the polymer foam. The ceramifiable silicone rubber can have a polysiloxane matrix with inorganic flux and refractory particles that ceramify under high heat, such as temperatures specified by common fire test standards (e.g., 1850 F./1010 C. for two hours). The cable is configured to maintain a relatively coaxial relation between a center conductor and an outer conductor even under aforementioned fire tests. Another layer of ceramifiable silicone rubber surrounds the outer conductor and continues to insulate it from the outside if a low-smoke zero-halogen (LSZH) jacket burns away.

A method for manufacturing a conductive wire includes conducting a continuous casting of a conductive alloy material at a casting rate of not less than 40 mm/min and not more than 200 mm/min to form a conductive wire with a primary diameter, the conductive alloy material containing not more than 1.0 mass % of an added metal element, reducing a diameter of the conductive wire with the primary diameter to form a conductive wire with a secondary diameter, heat treating the conductive wire with the secondary diameter so that tensile strength thereof is reduced to not less than 90% and less than 100% of tensile strength before the heat treating, and reducing a diameter of the conductive wire with the secondary diameter and the reduced tensile strength to generate a logarithmic strain of 7.8 to 12.0 therein to form a conductive wire with a tertiary diameter.

A method for manufacturing a conductive wire includes conducting a continuous casting of a conductive alloy material at a casting rate of not less than 40 mm/min and not more than 200 mm/min to form a conductive wire with a primary diameter, the conductive alloy material containing not more than 1.0 mass % of an added metal element, reducing a diameter of the conductive wire with the primary diameter to form a conductive wire with a secondary diameter, heat treating the conductive wire with the secondary diameter so that tensile strength thereof is reduced to not less than 90% and less than 100% of tensile strength before the heat treating, and reducing a diameter of the conductive wire with the secondary diameter and the reduced tensile strength to generate a logarithmic strain of 7.8 to 12.0 therein to form a conductive wire with a tertiary diameter.

A fire resistant coaxial cable and method of making is described that has a 2-part dielectric made of a polymer foam and a ceramifiable silicone rubber. The polymer foam, which can be polypropylene or other polymers, leaves little-to-no residue in the cable that causes electromagnetic loss when upon burning. The polymer foam can be extruded over a center conductor using an inert gas, such as nitrogen, to propagate the foam, ensuring little-to-no residue in the cable. The ceramifiable silicone rubber can be extruded over the polymer foam. The ceramifiable silicone rubber can have a polysiloxane matrix with inorganic flux and refractory particles that ceramify under high heat, such as temperatures specified by common fire test standards (e.g., 1850 F./1010 C. for two hours). The cable is configured to maintain a relatively coaxial relation between a center conductor and an outer conductor even under aforementioned fire tests. Another layer of ceramifiable silicone rubber surrounds the outer conductor and continues to insulate it from the outside if a low-smoke zero-halogen (LSZH) jacket burns away.

A method of installing a fire resistant coaxial cable is described in which the cable has a 2-part dielectric made of a polymer foam and a ceramifiable silicone rubber. The polymer foam, which can be polypropylene or other polymers, leaves little-to-no residue in the cable that causes electromagnetic loss when upon burning. The polymer foam can be extruded over a center conductor using an inert gas, such as nitrogen, to propagate the foam, ensuring little-to-no residue in the cable. The ceramifiable silicone rubber can be extruded over the polymer foam. The cable is configured to maintain a relatively coaxial relation between a center conductor and an outer conductor even under aforementioned fire tests. Another layer of ceramifiable silicone rubber can surround the outer conductor and continue to insulate it from the outside if a low-smoke zero-halogen (LSZH) jacket outer layer burns away.

Systems and methods presented herein provide reduced weight cabling using carbon nanotubes. In one embodiment, a cable comprises a conductive core comprising a strand of carbon nanotubes electroplated with silver and copper, a shielding surrounding the core along a length of the cable, and a jacket surrounding the shielding along the length of the cable.

The invention relates to a method for producing a stranded inner conductor (1), and to a coaxial cable (9). In a first step, a stranded inner conductor (2) is provided, which consists of several wires (3) twisted together. Then the stranded inner conductor (1) is rotary swaged by means of a rotary swaging device (10). In a further step, the rotary swaged stranded inner conductor (3) is enclosed with a dielectric (4). In a further step, the dielectric (4) is enclosed with an outer conductor (5) and a cable sheath (6).

A method for manufacturing a conductive wire includes conducting a continuous casting of a conductive alloy material at a casting rate of not less than 40 mm/min and not more than 200 mm/min to form a conductive wire with a primary diameter, the conductive alloy material containing not more than 1.0 mass % of an added metal element, reducing a diameter of the conductive wire with the primary diameter to form a conductive wire with a secondary diameter, heat treating the conductive wire with the secondary diameter so that tensile strength thereof is reduced to not less than 90% and less than 100% of tensile strength before the heat treating, and reducing a diameter of the conductive wire with the secondary diameter and the reduced tensile strength to generate a logarithmic strain of 7.8 to 12.0 therein to form a conductive wire with a tertiary diameter.

A method in the manufacturing of an insulated electric high voltage DC termination or joint includes the steps of providing an insulated electric high voltage DC cable including an inner conductor; a polymer based insulation system, the polymer based insulation system comprising an insulation layer and a semiconducting layer; and an outer grounding layer; removing the grounding layer and the semiconducting layer in at least one end portion of the high voltage DC cable, thereby exposing the insulation layer in the at least one end portion of the high voltage DC cable; covering the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable by a cover impermeable to at least one substance present in the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable in a non-homogenous distribution; subjecting the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable for a heat treatment procedure, while being covered by the cover, thereby equalizing the concentration of the at least one substance in the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable; and removing the cover. Instead of using a temporary cover, which is later removed, as the impermeable barrier, a field grading adapter or joint body mounted at the end of the DC cable during the manufacturing of the high voltage DC termination or joint may be used.

A method in the manufacturing of an insulated electric high voltage DC termination or joint includes providing an insulated electric high voltage DC cable including a high voltage DC conductor, a polymer based insulation system surrounding the high voltage DC conductor, the polymer based insulation system including an insulation layer and a semiconducting layer surrounding the insulation layer, and a grounding layer surrounding the semiconducting layer, removing the grounding layer and the semiconducting layer in at least one end portion of the high voltage DC cable, thereby exposing the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable, mounting a field grading adapter or joint body in the at least one end portion of the high voltage DC cable, thereby covering the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable, the field grading adapter or joint body being part of the high voltage DC termination or joint, wherein at least one substance is present in the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable in a non-homogenous distribution; and subjecting the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable for a heat treatment procedure, while being covered by the mounted field grading adapter or joint body, thereby equalizing the concentration of the at least one substance in the insulation layer of the polymer based insulation system in the at least one end portion of the high voltage DC cable.