GB1341704A - Thermally-insulated pipeline sections - Google Patents

Abstract

1341704 Insulating pipes; insulating pipe joints BRITISH OXYGEN CO Ltd 19 April 1971 [13 April 1970] 17541/70 Headings F2P and F2G A thermally insulated pipe-line section comprises a casing spaced from and surrounding a pipe, the intermediate space having an inlet and an outlet at its ends and being closed by end rings between the casing and the pipe, which protrudes from the end rings, the space containing solid thermal insulant. A copper or stainless steel pipe 1, Fig. 2, is surrounded by a mild steel or stainless steel casing 2, the end rings being of double cup form, of stainless steel, to allow for longitudinal thermal contraction of the pipe within the casing. The insulant 3 is of preformed mineral wool, rock wool, glass fibres and may be in powder form, preformed slabs or wrapping, or consist of a porous mass formed in situ from an aqueous slurry or from a foamed plastics, e.g. polyurethane. The inlet 6 and outlet 7, provided at each end of the casing 2, are for swaging the insulant with dry incondensible gas. Two such pipe sections are coupled by a sleeve 8 joining pipes 1; insulant 9 such as above surrounds the sleeve 8 and aluminium foil cladding 10 is applied over adjacent casings 2 and the insulant 9. Finally P.V.C. sealing tape 11 seals the cladding 10 to the casings 2 and adjacent vents 6, 7 are connected. An alternative means of allowing for thermal contraction, Fig. 3, is two pipes 24, 26 coupled with a bellows 28, the pipes being held by the end rings 18, 38. An intermediate tube 20 accommodates the bellows 28 and extends to a central ring 16. The insulant 22 between tube 20 and casing 14 is in two semi-cylindrical halves.