GB839249A - Improvements in or relating to heat insulating blankets, e.g. for gas-conveying pipes - Google Patents

Abstract

839,249. Heat-insulation for pipes &c. BRITISH REFRASIL CO. Ltd. Aug. 2, 1956 [May 3, 1955], No. 12794/55. Class 99(2). A heat insulating blanket or panel, e.g. for the casings of gas turbines, ducts or pipes, comprises two spaced skins 22, 23 of thin sheet metal enclosing a high-temperature insulation material such as fibrous silica, and includes between the skins, at least along opposite edges of the blanket, a light, internal, framework 10 of lattice girder type. As shown, the flexible, girder frameworks comprise flat, metal strips 13 each having one edge thereof folded over, and a corrugated metal strip 11 forming a web and secured to the flanges by spotwelding ; the frameworks are bent to a predetermined form. The skins are attached to the frameworks by spot-welding, the inner skin 22 being carried upwardly and bent outwardly to form a flange which is folded over together with the outer skin 23, the folded over edges being spot-welded together, crimped and bent to lie alongside the frameworks as shown at 26. The edges of the blanket transverse to the frameworks are sealed by folding the skins together as shown at 28. Flat strip elements 30, 31 are secured to the frameworks at each end of the blanket, and where two blanket sections are to be arranged in overlapping relation each edge of the outer skin has attached thereto a lacing strip 32 provided with eyelets 33 through which a wire is threaded to hold the sections together ; a girder 35 is interposed between the skins to relieve the latter of stress imposed by the strips 32. The skins may project beyond the girders and be secured to and folded over with the flanges of channels 40. Specification 839,250 is referred to.