COMPOSITION AND METHODS OF APPLICATION OF PHOSPHATE AND CHROMIUM COATS Russian patent published in 2003 - IPC

FIELD: application of protective coats on articles working under severe corrosion conditions. SUBSTANCE: proposed composition includes the following ingredients, mass-%: liquid oil waste from stage of rectification of cumene in production of cumene and acetone by cumene method - phenol resin, 0.05-0.50; vegetable tannic extracts, 20.0-40.0; soda ash, 1.0-3.0 and remainder being water. Proposed method includes treatment of surface first with phosphating solution of the following composition, g/l: zinc monosulfate, 12-14; zinc nitrate, 18-22; sodium phosphate, 5-10; orthophosphoric acid, 4-5 and remainder being water; then phosphating in solution at concentration of 15-30 g/l and impregnation of coat in solution at concentration of 80-100 g/l are performed followed by drying at temperature of 100-120 C. Proposed method of application of chromium coats includes electrolytic sedimentation of chromium on surface, phosphating of chromium coat, impregnation of it with aqueous solution of proposed composition at mass fraction of 0.5-10.0% and drying at temperature of 100-120 C. Proposed composition ensures obtaining of layer of thickness not exceeding 8 g/sq m. EFFECT: enhanced protective ability and corrosion resistance. 3 cl, 7 tbl, 3 ex