How can secondary anti-corrosion treatment of steel structures in industrial atmospheric environments ensure that the coating lasts for more than 5 years?

To ensure that the secondary anti-corrosion coating of steel structures in industrial atmospheric environments has a service life of over 5 years, it is recommended to follow these steps: 1. Surface treatment: First, carry out thorough surface rust removal; sandblasting or grinding can be used to eliminate the existing damaged coating and rust until a cleanliness level of Sa2.5 is achieved. 2. Primer selection: Use an epoxy zinc-rich primer, which possesses excellent corrosion resistance and adhesion properties, enabling effective protection of the steel substrate. 3. Intermediate layer: Epoxy limonite-based coating is used to increase the overall thickness of the coating and its corrosion resistance, thereby providing better mechanical strength and protection against corrosion. 4. Topcoat: Finally, a polyurethane topcoat or fluorocarbon topcoat is applied. These topcoats offer excellent resistance to ultraviolet rays and chemicals, which helps to extend the lifespan of the coating while also providing an attractive appearance. 5. Inspection and repair: After completion of the construction, inspect the thickness and adhesion to ensure that each coating layer is even and free of defects. During use, conduct regular inspections and repair any small areas of damage promptly. By applying the aforementioned system and following the proper construction procedures and maintenance practices, it is generally possible to ensure that the coating on steel structures in harsh industrial atmospheres lasts for more than 5 years. .