An insulation of cross-linked polymer is extruded about a cable conductor and cross-linked by means of heating in a vulcanization tube. The heating is effected by radiation energy, at least the main part of the radiation having wavelengths between 0.76 .mu.m and 4 .mu.m and a tube which is permeable...http://www.google.ca/patents/US4234624?utm_source=gb-gplus-sharePatent US4234624 - Method of applying an insulation of cross-linked polymer on a cable conductor
