Learn about anti-corrosion measures for steel structure surfaces
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Steel structure anti-corrosion coating is a new type of anti-corrosion coating for steel structures, developed on the basis of oil-resistant and anti-corrosive coatings. This coating is divided into primer and topcoat; in addition to that, it has a wider range of applications, and its color can be adjusted to various shades as needed. Corrosion-resistant coatings for steel structures are suitable for providing corrosion protection for storage tanks containing sewage, seawater, industrial water, gasoline, kerosene, diesel, jet fuel, gas, etc., as well as for oil and gas pipelines, bridges, grid structures, electrical equipment, and various chemical processing equipment. They can also be used to protect concrete structures from corrosion. 1. Improving the inherent properties of metals: that is, alloying treatment. Many scholars abroad have conducted research on the effect of various alloying elements on the seawater corrosion resistance of steel. It was found that alloy steels based on Cr, Ni, Cu, P, Si, and rare earth elements possess excellent corrosion resistance, and on this basis, a series of steels resistant to seawater corrosion were developed. However, due to economic and technological considerations, the aforementioned elements are not widely used in seawater-resistant steel. 2. Forming a protective layer: This involves applying a non-metallic or metallic protective layer; the metallic protective layer is typically created by subjecting the coated metal to phosphating, oxidation, and passivation treatments ； Non-metallic protective coatings mainly involve applying coatings, paints, plastics, enamel, mineral oils, etc., onto metal surfaces to form a protective layer. The purpose of both types of protective layers is to prevent the substrate from coming into contact with seawater, thereby replacing the reaction between the substrate and seawater and providing protection in this way.
There are mainly two ways to prevent corrosion on the surface of steel structures: First, improving the metal’s inherent corrosion resistance by using alloying processes, that is, by adding elements such as chromium (Cr), nickel (Ni), copper (Cu), and rare earth elements to the steel, thereby enhancing its resistance to corrosion. However, due to economic and technical constraints, this method has not been widely applied and is only used in specific fields. II. Coating protection layer isolation method 1. Non-metallic protection layers: Anti-corrosion coatings (such as epoxy paint, polyurethane paint), plastic coatings, enamel, greases, and other non-metallic materials are applied to the surface of steel structures to create a protective layer that isolates them from the environment. 2. Metal protective layer: Methods such as hot-dip galvanizing, aluminum spraying, and zinc spraying are used to coat the surface of the steel structure with a metal that offers better corrosion resistance; subsequent surface treatments such as phosphating, oxidation, and passivation are applied to further enhance this corrosion resistance. In practical engineering, protective coatings made of anti-corrosion paints are the most widely used. It is generally divided into primer (emphasizing adhesion and rust prevention) and topcoat (emphasizing appearance and isolation properties). It is suitable for various operating conditions (marine environments, industrial atmospheres, chemical areas), can be adjusted to a variety of desired colors, is easy to use, cost-effective, and reliable – making it the mainstream method for corrosion protection of steel structures. .