PICKLING: eliminate a surface layer of a stainless steel product.

when the steel undergoes both heating to high temperatures in the presence of atmospheric oxygen as occurs in the processes of forging, rolling, annealing heat treatments, and following mechanical processing, welding, etc. Carrying out the pickling is essential to restore the intrinsic conditions that make stainless steel such and avoid a principle of corrosion: allowing the natural exchange with the oxygen that creates the passive layer to avoid that when the final component is put into operation, it does not the conditions are created for localized corrosive phenomena.

Degreasing is the preliminary phase that allows the removal of fats, oils, resins and other impurities that optimizes the surface, preparing it correctly for subsequent treatments such as pickling and passivation.

In the case of welded artifacts, it is recommended to carry out degreasing preferably before going into welding, at least in the enlarged area of ​​the joint or groove, with the aid of ad hoc products.

Avoiding degreasing means compromising the result of the pickling and / or decontamination and passivation treatments, making them partially incomplete or even ineffective.

Degreasing is most commonly done:

- With the use of acid-based detergents or even alkaline-based detergents - the latter most commonly used in finishing or pre-painting.

- With the use of non-chlorinated solvents, or with very hot water or steam.

- In case of use of acidic or alkaline degreasing products, it will be essential to rinse the surface thoroughly with cold water at high pressure.