Life of galvanized steel plate and color coated steel plate

First. galvanized steel plate

Galvanized steel plate because of the zinc layer coverage and sacrificial protection function, the service life is longer than the general hot-rolled or cold-rolled steel, that is, under a certain environment, such as uniform coating, the life of galvanized steel plate is proportional to the thickness of galvanized layer.

However, even if the amount of galvanized steel plate is the same, the life will change greatly in different environments or regions. For example, in urban, industrial areas, the air contains sulfur dioxide (SO2) gas, which can make rain or dew falling on the zinc layer acidic, so the life will be shortened. In addition, due to the presence of salt (NaCl) in the coastal zone, the corrosion rate is faster and the life span is more affected. In the rainy season, the coating is soaked by rain for a long time, or the temperature difference between day and night is too large and easy to dew, and the service life will be relatively reduced.

Two. color coated steel plate

On the other hand, the use of color coated steel plate in this special or harsh environment, the steel plate in addition to the protection of zinc, the organic coating on the zinc layer also provides coverage resistance to prevent rust, so the service life is longer.

The coating of color coated steel plate can be selected according to the needs of the environment, such as polyester, silicon modified polyester, polyvinyl chloride plastic sol, polydifluoroethylene,....... It is necessary to achieve the best combination between the cost and the service life.

If the roof wall of a building or factory is regularly washed by natural rain, the life is longer; Unwashed areas will have a reduced service life due to the accumulation of acid, salt and dust. Non-rinsed areas should be sprayed or brushed regularly with water, or designed to minimize non-rinsed areas. On the other hand, in most areas, Low Pitch roofs (0 ~ 5°) have a shorter life with a higher pitch, which is related to the degree of easy accumulation of pollutants.