SIMPLE STRUCTURE BY PLASTIC MATERIAL, MANUFACTURE OF THE SI-MPLE STRUCTURE AND DEVECE FOR MANUFACTURING SIMPLE STRUCTURE

摘要

In order to produce a good cross-laminated film structure with a reduced, predetermined connection between the plies, or in order to produce a tubular product whose cooling can be more precisely controlled and which is stiffer, a unitary tubular product having an inner layer 9 and an outer layer 10 connected together by a bi-planar mesh formed of helical ribs 13, 14 bonded at their cross-over points 15 is produced in a single coaxial tubular extrusion process, the structure being integrally or confluently extruded. The extruder die head has annular flow channels 7, 8 having closely-spaced die grooves 7b, 8b.