Introduce several corrosion prevention measures for steel structures

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Here are several corrosion prevention measures for steel structures: 1. Weathering steel – Steel with better corrosion resistance than ordinary structural steel is known as weathering steel; it typically contains metals such as phosphorus, copper, nickel, chromium, and titanium, which form a protective layer on the metal surface to enhance its corrosion resistance. Its low-temperature impact toughness is also better than that of ordinary structural steels. 2. Hot-dip galvanizing: Hot-dip galvanizing involves immersing rust-removed steel components in molten zinc at a temperature of around 600°C, so as to form a zinc layer on the surface of the steel components. Thus achieving the purpose of corrosion prevention. The advantages of this method are a long service life, a high degree of industrialization in production, and stable quality. Therefore, it is widely used in outdoor steel structures that are severely affected by atmospheric corrosion and are difficult to maintain. Such as a large number of transmission towers, communication towers, etc. 3. Thermal spray aluminum (zinc) composite coating – This is a long-lasting corrosion protection method that offers comparable corrosion resistance to hot-dip galvanizing. The specific procedure is to first perform sandblasting on the surface of the steel components to remove rust, revealing a metallic shine and creating a rough surface. Then, the continuously fed aluminum (zinc) wire is melted using an acetylene-oxygen flame or an arc spraying machine, and blown onto the surface of the steel components with compressed air. Finally, capillaries are filled with coatings such as epoxy resin to form a composite coating. The advantage of this process is its strong adaptability to component dimensions, with virtually no restrictions on the shape and size of the components. 5. Coating method: The corrosion resistance provided by the coating method is generally inferior to that of long-term corrosion prevention methods. Therefore, it is more commonly used in indoor steel structures or in outdoor steel structures that are relatively easy to maintain. Its cost per use is low, but maintenance costs are high when used outdoors. The first step in applying the coating method is rust removal. A high-quality coating depends on thorough rust removal. Therefore, for coatings with high requirements, sandblasting or shot blasting is generally used to remove rust, reveal the metallic luster, and eliminate all rust and oil stains. The coating applied on-site can be manually derusted. The choice of coating should take the surrounding environment into account. Different coatings have varying tolerances to different corrosion conditions. 6. Cathodic protection: A more reactive metal is applied to the surface of steel structures to replace the steel and prevent corrosion. It is commonly used in underwater or underground structures.