Pulp-insulated conductor cable

摘要

A cable of this invention includes a number of pulp-insulated conductor pairs per unit of cable cross-sectional area which is substantially greater than in prior art cables. Each pulp-insulated conductor includes a metallic conductor enclosed in a composite insulation cover which has a controlled dielectric constant and a controlled adhesion of the cover to the conductor. The composite cover comprises a pulpous material and a layer of adhesive material which is interposed between the conductor and the pulpous material. The layer of the adhesive material bonds the pulpous material to the conductor and allows a reduced thickness of pulpous material without degrading the transmission characteristics of the cable. Also, the mechanical integrity of the insulation cover permits the moisture content of the pulpous material to be reduced and the density increased over that achieved in prior art pulp-insulated conductors without causing bare spots in the insulation. The changes in moisture content and density reduce the compressibility of the insulation. This is of help in maintaining a suitable mutual capacitance for the cable as well as allowing increased packing of conductor pairs without displacing insulation.