METHOD AND APPARATUS FOR MANUFACTURING COAXIAL CABLE

摘要

In the dual extrusion manufacture of an insulated coaxial cable having one or more spiral spacing rib(s) wrapped around an inner conductor and surrounded by a tubular sheath, the longitudinal contraction of the sheath during cooling and the attendant warp curvature of the rib is avoided by providing a sizing device having a central die portion with vacuum exhaust holes therein. Water from a cooling pool is drawn in through the clearance space between the sheath and the die portion as the cable passes therethrough to pre-cool and lubricate it, and one or more dies are provided in the cooling pool to prevent the longitudinal contraction of the sheath and thereby avoid any appreciable rib inclination or curvature.