Pickling cleans stainless steel surfaces and promotes good corrosion resistance by removing contamination which may have been caused by welding, heat treatment and fabrication operations.

Passivation is the term given to the
formation of a chrome oxide layer, which provides stainless steel with its corrosion resistance. This important
feature will occur naturally on a properly pickled service, but the process can be speeded up by chemical immersion.

The importance of pickling cannot be over stressed, because apart from the aesthetic benefits which pickling
provides, a stainless steel product which is not pickled will have an inferior
resistance to corrosion, which may
compromise its service life.