Method for forming a shield connection of a shielded cable with the steps of pushing a sleeve onto a shield of a cable, inserting the cable with the sleeve into a magnetic pulse welding coil, and energizing the magnetic pulse welding coil with a current pulse in such a way that the sleeve is joined to the shield with a material bond.

Systems and methods for tamper proof cables are described herein. In certain implementations, a system includes one or more pieces of equipment and one or more tamper proof cables connecting the equipment within a network. A tamper proof cable includes a core that provides a transmission medium through the cable; an insulator enveloping the core; a first conductive braid encircling the insulator; a dielectric enveloping the first conductive braid; and a second conductive braid encircling the dielectric, the first and second conductive braids, and the dielectric forming a capacitor. The system includes one or more detectors, each detector coupled to the tamper proof cables, each detector and an associated capacitor forming a tuned circuit, the detectors providing a signal when an associated portion of the tamper proof cables is tampered with; a monitor coupled to the detectors that notifies an infrastructure management system when the signal is received.

An electromagnetic shielding material includes multiple strands of an electrically conductive yarn that are arranged as a braided, knitted, or woven mesh. Each strand of the electrically conductive yarn comprises one or more electrically conductive filaments; each electrically conductive filament comprises a core of a first electrically conductive material surrounded by a sheath of a second electrically conductive material different from the first electrically conductive material. The first electrically conductive material exceeds the second electrically conductive material with respect to electrical conductivity, while the second electrically conductive material exceeds the first electrically conductive material with respect to one or more of tensile strength, corrosion resistance, or one or more other mechanical or chemical properties or characteristics. In many examples, the first electrically conductive material includes copper and the second electrically conductive material includes stainless steel.

A production method for a headline sonar cable characterized by steps of: a. providing a first strength member (14); b. coupling to strength member (14) a conductor (122); c. forming a layer of polymeric material about the combination of strength member (14) and conductor (122) while ensuring that the conductor remains slack; d. forming a flow shield around the layer of polymeric material, thus forming an elongatable internally located conductive structure; and e. braiding a strength-member jacket layer (52) of polymeric material around the elongatable internally located conductive structure while ensuring that the conductor is slack when surrounded by the jacket layer (52).

For another embodiment, an optical fibre is wrapped around the exterior of the layer of polymeric material within which is enclosed a braided conductor formed about the first strength member (14). Other embodiments employ further thermo-plastic layers and further sheaths and further conductors.

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 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.

The present disclosure relates to a composite cable, which comprises a first wire assembly and a second wire assembly, and each wire of the second wire assembly is surrounded by an insulating layer. The composite cable further comprises: a sheath made of insulating material and configured to enclose the first wire assembly and the second wire assembly; and a shield comprising different kinds of metal wires and configured to surround the first wire assembly, wherein the first wire assembly is capable of transmitting signals, and the second wire assembly is capable of transmitting power supply. The composite cable according to the present disclosure is excellent in shielding performance for different requirements.

Systems and methods for tamper proof cables are described herein. In certain implementations, a system includes one or more pieces of equipment and one or more tamper proof cables connecting the equipment within a network. A tamper proof cable includes a core that provides a transmission medium through the cable; an insulator enveloping the core; a first conductive braid encircling the insulator; a dielectric enveloping the first conductive braid; and a second conductive braid encircling the dielectric, the first and second conductive braids, and the dielectric forming a capacitor. The system includes one or more detectors, each detector coupled to the tamper proof cables, each detector and an associated capacitor forming a tuned circuit, the detectors providing a signal when an associated portion of the tamper proof cables is tampered with; a monitor coupled to the detectors that notifies an infrastructure management system when the signal is received.

An object of the present invention is to prevent, as much as possible, a braid from having inductance. A tubular conductive braid includes first conductive wires that describe a helix and second conductive wires that describe a helix in a direction opposite to the first conductive wires about a helix axis that is the same as a helix axis (X) of the first conductive wire, the first conductive wires and the second conductive wires being combined so as to form a tubular shape. The first conductive wires and the second conductive wires are electrically and mechanically connected at multiple locations on a line that extends along the helix axis.