Valuable Information About "Refined Stainless Steel; General Working Principles For The Handling; Of Appliances Made From "Refined Stainless Steel - Hupfer BDC/50-50 Manual De Instrucciones

Coolstapler - basket stacker with cooling by circulating air
43.3000.3

Valuable information about "refined stainless steel"

The resistance to corrosion of stainless steels is based on a passive layer
which is formed on the surface when oxygen is admitted. The oxygen in the
air is sufficient for the formation of the passive layer, so that faults or damage
to the passive layer can be remedied again automatically by mechanical ac-
tion. The passive layer develops or reforms more quickly when the steel
comes into contact with flowing water containing oxygen. A further increase in
the effect is achieved by acids having an oxidising action (nitric acid, oxalic
acid). These acids are used if the steel has been severely chemically stressed
and therefore has largely lost its passive layer. The passive layer can be
chemically damaged or disrupted by agents having a reducing (oxygen-con-
suming) action when the steel comes into contact with them in concentrated
form or at high temperatures. Such aggressive substances are for example:
• substances containing salt and sulphur
• chlorides (salts)
• seasoning concentrates such as mustard, vinegar essence, seasoning
cubes, saline solutions, etc.
Further damage can occur due to:
• extraneous rust (e.g. from other components, tools or rust film)
• iron particles (e.g. grinding dust)
• contact with non-ferrous metals (element formation)
• lack of oxygen (e.g. no admission of air, water with a low oxygen contend).

General working principles for the handling

of appliances made from "refined stainless steel"

Always keep the surface of appliances made from stainless steel clean and
accessible to the air.
Remove layers of limescale, grease, starch and egg-white daily by cleaning.
Corrosion can occur underneath these layers due to lack of air admission. No
bleaching and chloride-containing cleaning agents should be used.
If no special cleaning recommendations are given, low-chloride cleaning
agents should be used in any case.
After each cleaning operation remove all cleaning agent residues by rinsing
with copious fresh water. Afterwards the surface should be thoroughly dried.
Do not bring parts made from stainless steel into contact with concentrated ac-
ids, seasonings, salts etc. for longer than is absolutely necessary. Acid fumes
which form during cleaning of tiles also promote the corrosion of "refined stain-
less steel".
Avoid damaging the surface of the stainless steel, particularly by metals other
than stainless steel. Residues of extraneous metals produce extremely small
amounts of chemical elements which can cause corrosion. In any case, con-
tact with iron and steel should be avoided because that leads to extraneous
rust. If stainless steel comes into contact with iron (steel wool, swarf from
pipes, water containing iron), this can be the trigger for corrosion. Therefore
for mechanical cleaning use exclusively refined steel wool or brushes with nat-
ural, plastics or refined steel bristles. Steel wool or brushes with unalloyed
steel lead to extraneous rust due to abrasion. Fresh rust sites can be eliminat-
ed using gentle abrasives or fine abrasive paper. More severe rust sites can
be washed away with warm 2 – 3 % oxalic acid solution. If these cleaning
agents fail, treatment with 10 % nitric acid is necessary.
Caution! This should only be carried out by technically trained staff observing
the existing regulations!
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