Heliogravure printing cylinder, is made from two concentric metal tubes with gap between filled with expanded plastic foam

摘要

The printing cylinder (1) consists of two concentric and close metal tubes (2, 3) with their ends closed by covers (4, 5), at least one of which has one or more holes or perforations (6, 7) connected to the space (8) between the tubes, which is filled with an injected expanded foam (9). The outer tube is fixed to the two end covers by welding, and the inner one, which is shorter is fitted into a circular reinforcing element on the inside of each cover.