What methods are used for the secondary anti-corrosion coating of equipment and steel structures during the maintenance of petrochemical plants?

During the maintenance of petrochemical plants, the following methods are generally recommended for applying a secondary anti-corrosion coating to equipment and steel structures: 1. Surface treatment: First, the surface of the equipment and steel structures must be thoroughly cleaned and rust-free; the existing coating and rust can be removed using sandblasting or manual grinding to achieve a cleanliness level of Sa2.5. 2. Primer selection: Apply an epoxy zinc-rich primer, as this type of primer provides excellent rust resistance and adhesion. 3. Intermediate layer: The use of epoxy intermediate coats increases the thickness of the coating and its corrosion resistance, which helps to improve overall durability. 4. Topcoat: Finally, a polyurethane topcoat or a fluorocarbon topcoat is applied. These two types of topcoats possess excellent weather resistance and UV resistance, enabling them to effectively protect the underlying coatings and extend the lifespan of the coating system. Throughout the painting process, it is necessary to ensure that each layer of paint dries before applying the next layer, in order to avoid adverse reactions between the layers. Furthermore, the thickness of each coating should meet the design requirements to ensure the ultimate corrosion resistance and service life. By following this method, the anti-corrosion coating of equipment and steel structures can typically maintain its effectiveness for over 5 years. .

This post was last edited by Wang Wei2 on 2025-4-11 07:02. The metal surface can be treated in a non-precision manner (without sandblasting); coatings can be applied provided that the metal surface does not require sandblasting, and when the surface treatment reaches St2 level, coating is possible. The image below shows the construction process of low-surface treatment.