When the products have been completely stripped, the metal is ‘bare’ and is exposed to the elements. A natural response to this is for the ‘bare’ material to oxidise. This leads to the formation of corrosion on products that do not have corrosion-resistant properties. To halt this process, a preservation layer can be applied to the products as a post-treatment. In that case, the products are immersed in a water-based oil emulsion.
This temporarily protects the parts from oxidising/rusting, giving you ample time to re-treat them, for instance, by applying a new coating. The party that applies the coating must first degrease the product. This is because the oil emulsion creates a layer that is corrosion resistant but that is not suitable for painting.