METHOD OF CONVERING CORE WIRE FOR COMMUNICATION CABLE WITH INSULATOR

摘要

PURPOSE:To reduce loss and improve crosstalk characteristics and reliability by passing a core wire covered with an insulator of a foamed structure through a heating die to cause fusing of only the surface of the foamed insolator. CONSTITUTION:A conductor 1 is passed through a nipple 5 in an insulator extruder 3 to cover it with a foamed insulator 2 extruded from a screw 4 in a die 6. The conductor 1 emerging from the extruder 3 is passed through an insulator surface fusing die 7 having an inner diameter equal to or smaller than the outer idmeter of the insulator provided on the conductor in the preceding stage and elevated to a high temperature by a heater 8. In this way, a superficial portion of the insulator is fused to collapse the cores in this portion so as to form a smooth and solid structure, so that it is possible to eliminate deformation and intrustion of water and thus permit reduction of loss and improvement of crosstalk characteristics and reliability.