With metal coated steel, such as Zinc, ACMS, HDG and Pregal, including MAXI-TUBE® and ALLGAL® products, attention should be paid to the conditions of transport and storage to avoid the possibility of damage or wet-storage stain.
A corrosion known as ‘white rust’ can occur on freshly zinc-coated products that are transported or stored under damp and/or badly ventilated conditions.
This corrosion is frequently superficial, despite its bulkiness, and even though it can be unattractive, it is not usually detrimental to the other properties of the coating.
All steel and steel-related products need to be stored in a stable configuration. That means avoiding contact with corrosive agents such as acids, alkalis and salts and keeping away from excessive moisture.
The packed product should be kept undercover in clean, dry and well-ventilated conditions. This is especially important for products in the lower size range as their bundle configuration restricts natural ventilation.
Storage under covers which restrict ventilation (e.g tarps) is not recommended.
If products have to be stored outside, then the packs should be broken up and stacked with a wooden spacer between each layer. The stack should be on an incline so that any water can run off the product.
Never store steel in contact with cardboard or paper products, cinders, clinkers, unseasoned timbers or harmful chemicals.
White rust can be removed with a high pressure water cleaner, scrubbing brush or soft scouring pad. Kerosene can also be used.
If the metal coating is subject to excessively rough treatment some damage occur, the area should be cleaned and touched up with one of the following coatings:
Organic Zinc-rich primer
Inorganic Zinc silicate paint
Zinc metal spray
Apply these coatings in accordance with manufacturer recommendations.