MULTI-LAYER TUBE Russian patent published in 2003 - IPC

FIELD: manufacture of tubes, metallopolymer tubes with heat-insulating coat is particular. SUBSTANCE: tube has porous element embracing it on the outside. Proposed metallopolymer tube is made form aluminum or copper or alloys on their base; thickness of tube wall ranges from 0.1 mm to 7.0 mm; tube is provided with polymer coat applied to inner and outer surfaces, 0.1 to 3 mm thick. Porous element is made from foamed polyolefin at density of 100 to 500 kg/cu m. Ratio of outer diameter D_p.el of porous element to outer diameter D_m.p.t. of metallopolymer is no more than 1.7. EFFECT: extended assortment of tubes. 7 dwg