METHOD OF HEAT INSULATION OF PIPE LINES Russian patent published in 2003 - IPC

FIELD: thermal protection of pipe; steam and hot water supply pipe lines; construction engineering. SUBSTANCE: proposed method consists in weakening radiant heat transfer and avoidance of convection between pipe line and surrounding medium by means of air cavities formed between pipe line and protective envelope; pipe line is provided with shields made from heat-conducting material; clearance δ between shields is determined depending on Rayleigh number Ra_* calculated beforehand and lying within Ra_*<10⁴; used as protective envelope is steel pipe whose inner surface is coated with heat-reflecting compound, aluminum powder, for example and its outer surface is coated with non-heat-conducting material, for example foam polyurethane. EFFECT: reduced heat losses; increased thermal resistance of insulation; avoidance of free convection. 1 dwg