Electric cable comprising a foamed polyolefine insulation and manufacturing process thereof

摘要

A process for manufacturing an electric cable (10) comprising at least one core comprising a conductor (1) and an insulating coating (2) surrounding the conductor (1) is described, the process comprising the steps of: providing a polyolefin material, a silane-based cross-linking system and a foaming system comprising at least one exothermic foaming agent in an amount of from 0.1% to 0.5% by weight with respect to the total weight of the polyolefin material; forming a blend with the polyolefin material, the silane-based cross-linking system and the foaming system; and extruding the blend on the conductor (1) to form the insulating coating (2). An electric cable (10) is also described comprising at least one core consisting of a conductor (1) and an insulating coating (2) surrounding said conductor (1) and in contact therewith, the insulating coating (2) consisting essentially of a layer of expanded, silane-crosslinked polyolefin material having an expansion degree of from 3 % to 40% .