ZAZZERI JK21 Installacion Y Mantenimiento página 9

Stainless steel.
Stainless steel is a ferrous alloy composed of various elements. The main binder is the iron (more than
50%) but the addition of other elements such as nickel, chromium and molybdenum gives the best
performance. Especially corrosion resistance is guaranteed by nickel, chromium and molybdenum.
Stainless steel has the property of creating a thin surface film of oxides that prevents the oxidation of
the contained iron.
The stainless steel we use is AISI 316L that contains in addition to nickel and chromium, also
molybdenum (2-3%).
Otherwise, for some products and in considerably lower quantities, AISI 304 may also be used, in
which nickel is still present, although in lower concentration, but not the molybdenum. In the product
documentation is clearly indicated when this kind of steel is used.
Resistance to the corrosion AISI 316L Resistance to corrosion AISI 304
In most cases it is possible to use products made with both kinds of stainless steel (AISI 316L or AISI
304), whereas for settings that have a more critical exposure (outdoor locations, especially if marine,
and pools), the choice of products made of AISI 316L is strongly recommended.
How properties of stainless steel are preserved
As before mentioned, the maintenance of stainless steel consists in preserving the thin layer of oxides
which forms the protective film, preventing that the iron contained in the steel has a direct contact with
the air. It is clear that any cause avoids the permanence of the oxide film on the surface of the steel
reduces the resistance to corrosion.
The main causes that can produce the oxidation of stainless steel at different levels are the following:
1. Ferrous remains left to decant on wet surfaces (not dried)
2. Limestone accumulated and not removed over time
3. Detergents with a chlorine or ammonia basis
In order to maintain an optimal state of the material and therefore also of the aesthetic characteristics
of the products, in case of the marine environment and near swimming pools, periodic and frequent
cleaning of the surfaces is recommended.
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