Hot dip galvanizing and powder coating
Hot dip galvanizing
This is the most effective method of imparting anti-corrosive properties to fences. The galvanising process itself takes place by immersing a suitably prepared component in a solution of liquid zinc at a temperature of 440-460°C. During the bath, diffusion of the liquid from the surface of the steel takes place, thus forming an anti-corrosion layer. The advantage of this method is that the coating is applied even in the most inaccessible places and inside the component in the case of closed sections.
Selected atmospheric corrosivity categories according to EN ISO 12944-5:
Corrosivity category: C2 Low atmospheric corrosivity.
Outdoors: Atmospheres with low pollution. Mainly rural areas.
Indoors: Unheated buildings where condensation may occur, e.g. warehouses, sports halls.
Galvanisation loss per year: 0.1 to 0.7 µm
Corrosivity category: C3 Medium atmospheric corrosivity.
Outdoors: Urban and industrial atmospheres, medium SO2 pollution. Coastal areas with medium salinity.
Indoors: Production areas with high humidity and some air pollution, e.g. food processing plants, laundries, breweries.
Galvanisation loss per year: 0.7 to 2.1 µm
| Element thickness | Zinc layer | Loss per year | Estimated durability of the coating | ||
|---|---|---|---|---|---|
| Atmospheric conditions C2 | Atmospheric conditions C3 | Atmospheric conditions C2 | Atmospheric conditions C3 | ||
| up to 1.5 mm | 45 µm | 0.1 to 0.7 µm | 0.7 to 2.1 µm | Over 60 years | 21 to 64 years |
| 1.5 to 3.0 mm | 55 µm | Over 75 years | From 26 to 78 years | ||
| 3.0 to 6.0 mm | 70 µm | Over 100 years | From 33 to 100 years | ||
| Over 6.0 mm | 80 µm | Over 110 years | From 38 to 114 years | ||
Powder coating
This is the application of electrified powder paint particles using an electrostatic method. The workpiece is then "baked" in an oven at a temperature of 180-200°C. A durable, aesthetically pleasing colour layer is then created.
In addition to its decorative properties, it is a method that enhances the anti-corrosiveness of the fence through the principle of interaction of coatings.