device for framstellning of rorformad casing with halstruktur especially netformig, using strengsprutning plastic

摘要

Appts. for the prodn. of a tubular jacket provided with openings, esp. a net-shaped jacket, by extrusion of a synthetic resin, esp. a thermoplastic material, has a cylindrical extrusion head with an annular split for forming the tubular jacket, and =1 cogwheel rollers which rotate around the axis of the draw plate in such a manner that the cogs of the wheels move through the walls of the extruded jacket to form perforations.