Application introduction of long-term protective coating for steel structure

       Large steel structures such as offshore lighthouses, large reservoir locks, water supply towers, offshore oil production facilities, tankers, spherical tanks, storage tanks, fuel tanks, carbonization towers, heat exchangers, chimneys, ship hulls, offshore platform steel structures, etc. It has been in the corrosive environment of marine atmosphere and industrial atmosphere for a long time. The steel structure in the atmospheric environment is affected by sunlight, wind and sand, rain and snow, frost and dew and changes in temperature and humidity throughout the year. Among them, oxygen and moisture in the atmosphere are the cause of outdoor steel structure. An important factor for corrosion, the industrial gases that cause corrosion of steel structures contain SO2, CO2, NO2, CI2, H2S and NH3, etc. Although the content of these components is small, the corrosion hazards to steel cannot be ignored, and SO2 has a relatively large impact. , CI2 can destroy the passivation film on the metal surface. These gases dissolve in water and are acidic, forming acid rain and corroding metal facilities.



Metal zinc and aluminum have great resistance to atmospheric corrosion. Spray zinc or aluminum on steel components, zinc and aluminum are negative potential and form sacrificial anode protection effect on steel, so that steel is basically protected. Thermal spraying technology is used to thermally spray zinc and aluminum on the surface of steel, plus sealing treatment to prepare a long-lasting protective coating. The corrosive medium is isolated to play a protective role; on the other hand, when the coating has pores, cracks and damage, because zinc and aluminum are a very active metal, it is easy to combine with oxygen to form a dense and hard layer. The oxidation protective layer effectively prevents further oxidation of the aluminum coating, thereby enhancing the service life of the steel surface. In addition, the sprayed zinc-aluminum coating has strong bonding force with the steel substrate, long coating life, good long-term economic benefits, and flexible process. It is suitable for long-term protection of important large-scale and difficult-to-repair steel structures. It can be constructed on site and repair time and place. flexible.