There are two galvanizing treatments for street light poles, one is called hot-dip galvanizing and the other is called cold galvanizing. So what is the difference between the two?
First of all, we need to know that these two methods are anti-corrosion treatment, so what is cold galvanizing? Cold galvanizing paint is a one-component new type of coating with extremely high zinc content, which is made of high-purity, high-activity zinc powder and special bonding Agents, additives, solvents. With a zinc content of more than 96%, it has electrochemical protection comparable to hot-dip galvanizing and excellent long-term anti-corrosion performance, low VOC content, room temperature drying, energy saving and environmental protection; simple construction, one-time thick coating, and good recoatability.
So what is hot-dip galvanizing? Hot-dip galvanizing is to immerse the derusted steel parts in a molten zinc solution at about 500°C to attach a zinc layer to the surface of the steel parts to achieve the purpose of corrosion protection. It is an effective metal anti-corrosion method, mainly used in metal structure facilities in various industries. Since France applied hot-dip galvanizing to industry in 1836, it has a history of 170 years.
However, the hot-dip galvanizing industry has been developed on a large scale with the rapid development of cold-rolled strip steel in the past 30 years. The production process of hot-dip galvanized sheet mainly includes: original board preparation → pre-plating treatment → hot-dip plating → post-plating treatment → finished product inspection, etc.
So what is the long-term effect of the anti-corrosion treatment principle of cold galvanizing: the pure zinc content of the zinc film is ≥96%, the salt spray resistance is ≥3000 hours, the coating system has an anti-corrosion cycle of more than 25 years, and its similar products have more than 50 years abroad Successful examples of the product; environmental protection: no isocyanate, benzene and other toxic chemical components; radiation resistance: this product is an inorganic substance, strong UV resistance; anti-slip: anti-slip coefficient ≥0.55, can be used for high-strength bolt connection surface Anti-corrosion; welding resistance: coated welding does not affect the welding quality, and the coating is not damaged by cutting and welding; high temperature resistance: continuous high temperature resistance is 400℃, instant heat resistance is 1200℃; low temperature resistance: -60℃; fast Dryness: The surface drying time is 15 minutes at 23°C, and the actual drying time is 2 hours.
The principle of hot-dip galvanizing is that the hot-dip galvanizing layer is formed in three steps when zinc is in the liquid state. The surface of the iron base is dissolved by the zinc solution to form a zinc and iron alloy phase layer; the zinc ions in the alloy layer further diffuse to the base to form zinc, The iron miscible layer; the surface of the alloy layer is wrapped with a zinc layer.
The best process difference is the cold spray zinc paint process: In terms of construction process, you only need to follow the normal paint spraying method (brushing, roller coating, spraying). It is recommended that the high-pressure airless spraying meets the requirements The minimum film thickness is 40 microns and the maximum film thickness is 120 microns. A complete coating system can protect steel structures for more than 25 years.
