Anti-corrosion primers are the first protective layer for metal structures. They provide adhesion to metal and barrier/cathodic protection against corrosion. Epoxy 2K: high chemical resistance, adhesion 1 point, thickness 60–100 μm. For petrochemicals, ships, tanks, bridges. Polyurethane: elasticity, abrasion resistance. Zinc-rich (80–95% Zn dust): cathodic protection — zinc corrodes instead of steel (sacrificial protection). For bridges, power line supports, port structures. Alkyd 1K: fast-drying (4–12 h), economical. Surface preparation: abrasive blasting Sa 2.5 (ISO 8501-1). GOST 25129-82. Cans 5–20 kg, buckets, barrels. Coating system ISO 12944: primer + intermediate layer + enamel. Corrosivity category C5-I/C5-M (industrial/marine atmosphere). Protection period: 15–25 years for 3-layer systems. Surface preparation: abrasive blasting Sa 2.5 — key to coating durability. Documentation: TDS, MSDS, adhesion protocol, thickness measurement.