The following information offers some guidance on the general care and maintenance of hot dip galvanized steel products:
Avoid long periods of exposure of your galvanized steel product to environments where the pH is below 6 and above 12. Outside the range of pH 6-12 the galvanized coating can suffer greater corrosion than normal.
Avoid direct contact of your galvanized steel product with dissimilar metals, such as brass and copper, particularly in corrosive environments. Where dissimilar metals are to be used together ensure that there is an insulator between the dissimilar metal and the galvanized product.
Do not constantly abrade clean your galvanized product and, where possible, avoid abrasive washing of your galvanized product altogether. One of the ways in which galvanising protects steel from corrosion is by the development of a thin barrier film of insoluble zinc corrosion products (known as a patina) on the outer surface of the galvanized steel through exposure to the atmosphere. Abrasive cleaning will wash away this protective patina and the galvanized article will have to build up this barrier protection again, consuming more of the zinc. Constant abrasive cleaning will consume the zinc more quickly and therefore may reduce the life of your galvanized steel product.
Galvanising may be cleaned using a water-based emulsifier, alkaline-based cleaners with a pH of 12 or lower or organic solvents. Then rinse the area with fresh water and simply wipe clean with a soft cloth. Please consult the your galvanizer or the GAA if you have any concerns in regards to cleaning your product.
For galvanising products situated in a highly corrosive environment eg. coastal, heavy industrial, etc it is recommended the product be rinsed with potable water on a regular basis, particularly under sheltered conditions (i.e. not exposed to rain and sun).
Avoid long term storage of any galvanized product in damp and poorly ventilated conditions. Ensure the storage location is dry and there is effective ventilation. v If there is physical damage to the galvanized coating of the product (e.g. coating is chipped or fabrication after galvanising has taken place), it is recommended that the damaged area be repaired in one of the following ways in accordance with AS/NZS 4680.
Material supplied by the GAA.