Wires require high electrical conductivity, and should […]
Wires require high electrical conductivity, and should be flexible and have sufficient mechanical strength, but also to facilitate the welding performance. Electrolytic copper has such a feature, it is the main cable core wire material. Copper wires used in Communication Cable require very smooth, crack-free, glitch-free and generally require no solder joints, although this is often not easy to do, but solder joints within each manufacturing length are not to exceed 2 -3, the resistance at the weld does not exceed 5% of the wire diameter of the same diameter with a length of 15 cm. Do not use welding with corrosive flux. Submarine cables are not allowed to have solder joints when manufactured. Local telephone communication cable diameter 0.5,0.6,0.7 mm, long-distance communication cable diameter 0.8,0.9,1.0,1.2,1.4 mm. In order to save copper consumption, the current consideration to replace the copper wire with aluminum wire.
We hope that the insulating material of the cable conductor has high resistivity, low dielectric loss, low dielectric constant and high flexibility. Currently widely used as: paper, polyethylene and so on.
Communication cable used as insulators in telecommunications cables are made from sulphate wood pulp. Requires paper containing impurities, less acid, alkali, to have higher mechanical properties. For high-frequency cable phone paper, but also requires uniform thickness, medium loss. China's telephone paper has DH-40, DH-50, DH-75 three specifications, the thickness of 0.04,0.05,0.075 mm. Some local communication cable directly attached to the wire pulp as an insulating layer. Cables used in communication cable have a thickness of 0.08 mm, and in special cases use a 0.12 mm thick cable.
Polyethylene is a white, translucent, soft, tough solid that smells greasy waxy. It has excellent physical, chemical, electrical insulation properties, in the 25-50 MHz band below the most stable electrical properties of polyethylene. At the same time it has anti-pull off, solid, flexible, cold, almost non-hygroscopic and acid and other properties, it is a good high-frequency insulation materials. Its softening point is 1100C - 1150C, the general operating temperature range is -800C- + 700C after radiation treatment, the operating temperature range of -800C- + 2000C or even up to 3000C.