The normal rust prevention treatment for steel flanges include yellow (Golden) paint Coating, black paint coating or black phosphating treatment, varnish paint coating, varnish antirust oil coating, electro galvanizing coating (Cold), hot dip galvanizing coating etc.
Golden Yellow Paint Coating
Black Paint Coating or Phosphating Treatment with Black Color
Varnish Paint Coating
Varnish Light Oil Coating
Electro Galvanizing Zinc Coating(Cold Galvanizing Zinc, Color Silvery White or Golden , Coating thickness 20~30μm)
Hot Dip Galvanizing Coating (Coating Thickness 200μm around)