1,Dual anti-corrosion protection system
Hot dip galvanized substrate protection
By infiltrating steel with molten zinc at a high temperature of 500 ℃, an 80-86 μ m zinc iron alloy layer is formed, achieving metallurgical bonding and effectively isolating oxygen and moisture. The corrosion resistance life can reach more than 15 years.
The zinc layer has self-healing properties: when there is local damage, the surrounding zinc layer continuously protects the substrate through the sacrificial anode principle, avoiding rust diffusion.
Spray coating outer layer reinforcement
Electrospray polyester powder forms a coating with a thickness of ≥ 100 μ m, further enhancing its resistance to ultraviolet radiation, salt spray, and chemical corrosion, extending the overall anti-corrosion life to 20 years.
The plastic layer covers the hot-dip galvanized surface to prevent direct exposure of the zinc layer to oxidation losses caused by extreme weather conditions.
2,Adaptability to harsh environments
Temperature tolerance
The combination process of galvanizing and spray coating can withstand temperatures ranging from -50 ℃ to 75 ℃, and is suitable for areas with severe temperature differences such as the Nordic polar nights and equatorial deserts.
Mechanical protection performance
The hardness of the galvanized layer is higher than that of the steel body, and the adhesion of the spray coating is verified by the grid cut test (GB9286 standard), which can resist the impact of strong winds of level 14 and sand and gravel wear.
Through IP68/IP69K protection certification, it meets the complex environmental requirements of high salt spray, flood and waterlogging along the coast (such as a 3-meter rise in water level during flood season in Bangladesh projects).
3,Collaborative optimization of functionality and aesthetics
Color customization capability
Spray painting provides over 200 color options that can match urban landscape design requirements (such as matte white to reduce snow glare, and deep gray integrated into industrial color tones).
Surface quality improvement
Hot dip galvanizing eliminates burrs on the surface of steel, and the spray coating solidifies at high temperatures to form a smooth and dense film layer, avoiding traditional paint sagging and orange peel phenomena.
4,Full lifecycle cost advantage
Reduced maintenance costs
Compared to a single cold galvanizing solution (requiring 2-3 years of maintenance), the combination of galvanizing and spray coating extends the maintenance cycle to over 10 years, reducing the frequency of maintenance by 87% for projects in remote areas.
Detailed explanation of process flow
1,Hot dip galvanizing treatment
|
step |
technological requirements |
role |
|
acid pickling |
Removing surface oxides of steel using hydrochloric acid solution |
Remove rust and oil stains to ensure coating adhesion |
|
fluxing |
Immerse in ammonium zinc chloride solution to form an activated film |
Prevent secondary oxidation and promote the formation of zinc iron alloy layer |
|
Hot dip plating |
Immerse in molten zinc solution at 500 ℃ for ≥ 5 minutes |
Generate 80-86 μ m zinc layer to achieve metallurgical bonding |
|
Cooling |
Water or natural cooling to room temperature |
Fixed zinc layer structure to avoid cracking |
2,Electrostatic spraying treatment
|
step |
technological requirements |
role |
|
pretreatment |
Phosphating treatment enhances surface roughness |
Improve the adhesion of plastic powder to avoid peeling and detachment |
|
electrostatic spray |
40-80kV high-voltage electric field adsorption of plastic powder particles |
Achieve uniform coverage with a thickness error of ≤± 10 μ m |
|
High temperature curing |
Bake at 180-220 ℃ for 15-30 minutes |
Melting and leveling of plastic powder to form a dense protective film |
|
quality testing |
Testing adhesion through grid crossing method |
Ensure that the coating hardness is ≥ 2H and there is no orange peel phenomenon |
