METHOD OF APPLYING ANTICORROSIVE COAT ON INNER SURFACE OF PIPE Russian patent published in 1999 - IPC

FIELD: application of anticorrosive coats on inner surfaces of metal pipes used in oil producing and petrochemical industries for transportation of aggressive media. SUBSTANCE: corrosion-resistant metal sheets rolled in ferrules are placed at ends of pipe; these ferrules have inner beads. Then branch pipes are formed from them by electric arc welding of longitudinal edges of bands along length of their contact with metal of pipe and part of length of beads equal to thickness of coat; then unwelded part of flanges of branch pipes are beaded on ends of coat applied. Branch pipes thus formed are additionally secured to inner surfaced of metal of pipe by spot welding or by means of electrically welded rivets. Branch pipes may be made from corrosion-resistant metal bands provided with additional outer beads for forming outer flanges resting against ends of pipe. Beaded parts of branch pipe flanges are bonded to ends of inner coat of pipe. EFFECT: enhanced reliability of pipe line. 4 cl, 4 dwg