How to prevent corrosion of factory warehouse steel structure?
Three methods to prevent corrosion of steel structure in factory warehouse:
1、 Hot dip galvanizing anti-corrosion method
Hot galvanizing anti-corrosion technology is one of the widely used technologies in steel structure engineering, and it is also a steel anti-corrosion method with good use effect and good economic benefits. It is commonly used for outdoor steel structures with severe atmospheric corrosion and difficult maintenance.
In practice, the workpiece to be plated is immersed in a molten zinc bath and then coated to form a pure zinc coating on the steel surface and a zinc alloy coating on the secondary surface to prevent steel corrosion. Generally speaking, the hot-dip galvanized layer is dense and thin, generally about 30-50m. The surface of hot-dip galvanized parts used in the construction process shall be flat without peeling, missing plating, dripping, roughness, zinc binding, and residual solvent residue. At the same time, try not to design the mating surface parts, so as to avoid the yellow water flowing on the galvanized surface due to incomplete pickling or unclean pickling of the mating surface gap.
2、 Paint anti-corrosion method
The construction cost of anti-corrosion coating method for steel structure of factory warehouse is low, but the outdoor maintenance cost is high and the anti-corrosion effect is poor. Therefore, it is commonly used for indoor steel structures or outdoor factory warehouse steel structures that are relatively easy to maintain.
In fact, pure zinc powder is first dissolved in solvents, additives and film-forming materials to form a zinc rich primer, then brushed on the anti-corrosion workpiece and solidified on the workpiece surface through film-forming to isolate the immersion of corrosive media. When mechanical tools are used for coating and anti-corrosion, ingredients shall be explored, viscosity shall be adjusted, and the traveling speed of the sprayer shall be flexibly controlled according to the weather, temperature, humidity and other surrounding media at the construction site to avoid blank spraying caused by too fast traveling speed of the sprayer, or paint surface accumulation and sagging caused by too slow traveling speed, which will affect the later drying time. At the same time, paint 4-5 times during construction, and paint after the paint is dried to 80% or completely dry.
3、 Arc spraying anti-corrosion method
The arc spraying method for steel structure engineering has high bonding force, strong adaptability to component size, almost unlimited component shape and size, corrosion resistance, long wear resistance life, and can reach more than 10 months. At the same time, the anti-corrosion coating does not require any other maintenance during the service life of 10 months, so this method is usually used for underwater or underground structures.
During construction, the surface of steel members shall be sandblasted for rust removal to expose metal luster and make the surface rough. Then, the metal is burned and melted by the arc between two continuous feeding metal wires, and sprayed on the metal components that were previously sandblasted to form an arc sprayed zinc aluminum coating, forming a long-term anti-corrosion composite coating.
In addition, vertical cross spraying shall be conducted in an environment with relative humidity less than 85%. If vertical spraying is not possible, the inclination of the spray gun and the workpiece surface shall not be less than 45. Different steel structures have different anti-corrosion time, which depends on the actual requirements and operation. In order to use the steel structure safely to a large extent, it is necessary to do a good job of fire prevention and corrosion prevention.
