METHOD OF INSULATION OF STEEL PIPES Russian patent published in 1999 - IPC

FIELD: protection of steel pipes against corrosion in hot water supply systems, gas and oil lines; application of coats on outer surfaces of pipes. SUBSTANCE: cleaned surface of pipe is coated with porous layer of corrosion-resistant material, for example aluminium and pipe is heated to 70-90 C after which anticorrosive coat is applied by layers; used as anticorrosive coat is solution of phenol-formaldehyde resin, for example, phenol-formaldehyde lacquer; then reinforcing material is wound on pipe and pipe is heated to 160-200 C; glass fabric may be used as reinforcing material; then pipe is kept for 10 to 15 minutes and cooled after-wards. EFFECT: reliable corrosion protection at temperature up to 300 C and 100-% moisture content of medium contaminated with acids, alkalis and petroleum products; high dielectric and mechanical strength. 2 cl