GB1430752A - Method of manufacturing tubular articles and articles produced by the method - Google Patents

Abstract

1430752 Buoys MIDLAND POLYMER PRODUCTS & ENG Ltd 13 March 1973 [15 Dec 1971] 58197/71 Heading B7A [Also in Divisions B5 and F2] In making a sleeve, which when fitted on a hose or cable will provide heat insulation or protection or render it buoyant or will provide a buoy construction (Fig. 7, not shown), at least one layer of expanded polymer is wrapped round a former (which may form part of the completed article) and abutting edges and/or surfaces of the layer or layers are welded together by heat and pressure. The innermost layer may be welded to the former or to the hose or cable, alternatively, after fabrication it is split longitudinally to remove it from the former. The split may be sealed and the sleeve secured around the hose or cable by adhesive. In one form, four separate rectangular sheets of closed cell polythene, ethylene vinyl acetate copolymer or polypropylene are wrapped successively round a former (5, Figs. 1 and 2, not shown) and the abutting longitudinal edges welded together. A single sheet of material may be wound, swiss-roll fashion, about a former (5, Figs. 3 and 4, not shown), so that the continuous surfaces of the layers can be welded together. As shown, a single strip of material 11 is wound past a gas burner and rollers 12 and 13 to a further travelling pressure roller, which welds the edge and surface of the strip in a helix about the former 5. A number of passes in opposite directions may be made.