vaevd beklaednad foer papermaking machines and the like

摘要

A tube of layered material consisting of a first layer and a second layer, for use in transporting and storage of hydrocarbons, wherein said first layer consists essentially of polyethylene or polypropylene, and wherein said second layer constitutes a barrier layer for reducing the diffusion outward through said tube of hydrocarbons transported or stored within said tube and comprises polyethylene or polypropylene in combination with any component selected from the group consisting of butyl rubber, polyamide, and polyester. The first and second layers of the tube are coextruded.