| 摘要 |
PURPOSE:To restrict the tensile strength of the steel filament 1 from reducing with twisting working to the irreducible prininum, by intensively working the above steel filament 1 until the finish wire drawing by largely reducing the twisting number applying to the steel filament 1 which is one of large factors for breaking the wire, on the case that the steel filament 1 of the tensile strength >=250kgf/mm<2> is twisted. CONSTITUTION:The temporal twisting device 7 of twice wire twisting machine for twisting the single twisting structure composed of plural pieces of the steel filament 1 of the tensile strength >=250kgf/mm<2>, or the two layer twisting structure composed of the steel stranded core 2 made of plural pieces of the above steel filament 1 and plural pireces of the above steel filament 1 wound around this core 2 is set before the twice twisting, and the number of rotation of the temporal twisting device is made twofold or more of the number of rotation of the twice wire twisting machine and to its device, and the twist of the cord is removed by using the straightening unit 9 and the straightness is kept exactly. |
