Method and extrusion head for extruding a polymeric material

摘要

An extrusion method and head for depositing by extrusion a polymeric material intended, in particular, for the production of cables includes a core and a coating layer arranged at a radially outer position with respect of the core. The method includes the steps of feeding the polymeric material in a feeding duct of the extrusion head and of conveying a part of the polymeric material towards an undercut extending in the extrusion head in proximity of an end of the feeding duct. The method provides a sealing force between a head body and a conveyor element of the extrusion head exerted by means of the pushing action exerted by the polymeric material in the undercut in a direction substantially perpendicular to the longitudinal axis of the head body.