Abstract: A method for continously covering by extrusion, with a cross-linkable or vulcanizable material, a wire conductor around which a separating tape is longitudinally folded with overlapped lips. In the method, upstream of the extrusion step, a force of such a magnitude and orientation as to permit a controlled relative displacement of the overlapped lips, not greater than a pre-determined value, is applied to the separating tape. The extrusion head used in the method of the invention comprises, in the feed cavity for the taped conductor in advance of the male mold, a tubular element having an inner diameter close to that of the taped conductor but not mechanically secured in position within said cavity.