Hot-dip galvanizing is used to prevent rust and corrosion, so why does it still rust? I summarized 3 reasons to share with you.
First, there is a problem with the zinc layer
When plating parts, if the surface is not clean or is not properly pickled, there will be missing plating, resulting in an uneven zinc layer and easy rusting. In addition, if the zinc layer is too thin and does not reach the corresponding standard thickness, it will also cause the steel body to rust.
Second, there is a problem with the steel body
If the steel body that needs to be galvanized has been corroded and contains a large amount of oxygen content, these oxygen content will react with iron elements in a humid environment, causing the galvanized layer to rust.
Third, passivation is not complete
What is passivation? That is, the steel body is oxidized by a strong oxidant or electrochemical method, so that the surface of the steel body becomes inactive, just like forming a protective film. However, if the passivation is not complete, it will cause the galvanized body to become alkaline or rust.
In order to prevent galvanized pipes from rusting and extend their service life, try to avoid humid environments and avoid exposure to the sun and rain. Under normal circumstances, with proper maintenance, the service life of galvanized pipes can be as long as ten years.
