| 摘要 |
PURPOSE: To provide a conductivity-enhanced overhead power-transmission line by forming a plural annealed conductors-twisted layer around a twisted steel core so as to form a cable, and heat treating at a limited temperature to remove stress and to anneal. CONSTITUTION: The periphery of a high tensile strength steel center strands 18 is surrounded by plural twisted steel strands 20 so as to form a twisted steel core 14, and the same is coated with Al or Zn protective coat 16 on demand. While a rod made of high conductivity Al or Al alloy is annealed into a completely annealed state so as to manufacture a cross section circular conductor wire 32, and the plural conductor wires 32 are twisting wound on the steel core 14 so as to form a layer 38 to manufacture a cable 10. A layer 40 can be further added on the layer 38 on demand. The cable 10 is annealed at a limited temperature which hardly exerts harmful effect on the steel core 14 until the conductor wires 32 are nearly completely softened so as to remove stress. Thereby, it is possible to obtain an overhead power transmission line which has an excellent self damping characteristic and enhanced conductivity. |
