Several requirements for the anti-corrosion coating of carbon steel water cooler tube bundles

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Corrosion and scaling in carbon steel coolers have always been difficult problems for petrochemical companies to solve. There are many methods to prevent corrosion, such as proper material selection, rational design, electrochemical protection, surface coatings, improving operating conditions, the use of corrosion inhibitors, and scientific management. Using stainless steel tube bundles is too costly, and the Cl‑ ions in the medium will damage the passivation film, resulting in poor performance. The application technology of electrochemical protection in heat exchange equipment in refineries is not yet mature. The combined protection effect of protective coatings and electrochemical protection offers the best economic benefits. The corrosion prevention principle of non-metallic coatings is to isolate metal equipment from corrosive media; it not only improves corrosion resistance but also helps to save a large amount of precious metals and alloys. Coatings should meet the following requirements: (1) The coating itself must be resistant to corrosion in the medium. (2) It has a tight structure, is completely pore-free, and cannot be penetrated by the medium. (3) It has a strong bonding force with the base metal. (4) It should be evenly distributed over the entire protective surface, and the thickness should not be too great. (5) For the heat exchanger core, it does not affect the heat transfer efficiency or the anti-scaling performance.