Anti corrosion treatment method for steel structure surface

At present, users, designers and constructors of Steel structures still lack sufficient attention to the importance of long-term anti-corrosion of steel structures, and still stay on traditional anti-corrosion technology, and later maintenance may not keep up. Moreover, even traditional coating anti-corrosion may cause premature corrosion or damage to steel structures due to poor technology during construction. Now, the design and construction of steel structure anti-corrosion projects adopt a lifelong quality system. And the government has put forward clear life requirements for the design and manufacture of steel structure anti-corrosion. Therefore, no matter what technology is adopted for steel structure anti-corrosion, strict quality inspection and supervision must be carried out. Application scope of steel structure anti-corrosion

Large steel structures such as steel structure workshops, bridges, TV towers, high-voltage iron towers, lightning rod iron towers, offshore lighthouses, large reservoir gates, water supply towers, offshore oil production facilities, tank trucks, spherical tanks, storage tanks, oil tanks, carbonization towers, heat exchangers, chimneys, containers, ship hulls, offshore platform steel structures, etc., are all in the marine atmosphere and industrial atmosphere corrosion environment for a long time. If steel structures are to be used for a long time without large-scale maintenance, the best protection method is long-term coating protection, which can last for 20 to 30 years, with low maintenance costs and significant economic benefits.

Anti-corrosion surface treatment of steel structures

1. Cleaning of steel structure surface

Before surface treatment, the surface of the steel structure should be cleaned, including no welding spatter, no pores and other defects. The surface cleaning of the steel structure includes removing chemical reagents such as grease on the surface of the steel structure.

2. Surface treatment of steel structure

All steel structures need to be shot blasted or sandblasted before anti-corrosion paint is applied to remove various dirt attached to the surface of the steel, including: scale, rust, old coating, dust and grease. The surface treatment should comply with the rust removal level requirements in GB8923 standard "Rust level and rust removal level of steel surface before painting". After treatment, the surface of the steel structure must be sprayed with anti-corrosion paint within 48 hours. If there is rust on the surface of the steel structure, the surface treatment needs to be performed again.

3. Surface treatment inspection of steel structures

After all steel structures are treated, the construction team needs to conduct self-inspection according to the surface treatment requirements of the steel structures. If the surface roughness level of the steel structure does not meet the design requirements, the surface treatment needs to be carried out again until it meets the design requirements. The inspection personnel can only carry out anti-corrosion work after making records.

4. Choose a reasonable anti-corrosion paint construction plan

Choose a suitable anti-corrosion plan according to the environment where the steel structure is used. The main factors affecting the atmospheric corrosion rate are: relative humidity of the atmosphere; industrial pollution; salt.

Internationally, standard sample exposure tests are used to define the level of corrosion. This method is based on the thickness or mass loss data of low-carbon steel or zinc standard samples exposed for one year to determine the corrosion level of the environment.

5. Anti-corrosion paint construction process

After the surface treatment level of the steel structure is inspected and qualified, the anti-corrosion primer must be sprayed within 4-8 hours. If there is floating rust on the surface of the steel structure, it must be cleaned before the anti-corrosion paint can be sprayed.