Stainless steel valve is will never rust when it comes to stainless steel valves, we direct intuition is that stainless steel valve is never rust, would think that if we buy the stainless steel valve gave birth to rust, it is stainless steel.
Actually otherwise, stainless steel under certain conditions is also will rust.
Stainless steel has the ability of resistance to atmospheric oxidation, namely, stainless, also has in the medium containing acid, alkali, salt corrosion resistant ability, the corrosion resistance.
But the size of the stainless steel corrosion resistance was as the chemical composition of steel itself, environmental conditions and using medium type and change.
Such as 304 stainless steel valves, in dry clean the atmosphere, has absolute excellent corrosion resistance, but it will be moved to the coastal areas, in contains a great deal of sea salt fog, will soon be rusty, 316 valves is good.
So, not any kind of stainless steel, in any environment corrosion, no rust.
Why will rust stainless steel valves?
Let's analyze the reasons, the surface of the stainless steel valve is a layer of a very thin and fine and stable solid rich chromium oxide film, prevent oxygen to infiltration, oxidation, corrosion resistant ability.
Destroy this film once there is a certain factors, air or oxygen atoms in the liquid iron atoms will constantly infiltration or metal separation out unceasingly, and then forming loose iron oxide, metal surface are also constantly rust.
Therefore, the stainless steel are rusted.
Is what reason destroyed the membrane on the surface of the stainless steel, we illustrate the following: 1, the electrochemical corrosion.
Deposited on the surface of the stainless steel valve with other metal elements of attachments, or heterogeneous metal particles of dust in the humid air, attachments and stainless steel, the condensed water between the both together as a micro battery, triggers the electrochemical reaction, protective film.
2, stainless steel valve surface adhesion juice, organic matter in water is oxygen, organic acid, organic acid to for a long time and are on the surface of the metal corrosion.
3, stainless steel valve surface adhesion containing acid, alkali, salt substances, can lead to local corrosion.
4, with the help of pollution in the air (
Such as contains a lot of sulfur, oxidation of carbon, nitrogen oxide atmosphere)
, encounter condensed water to form sulfuric acid, nitric acid, acetic acid, liquid, chemical corrosion.
The above situation can lead to the destruction of the stainless steel surface protective film rust.
In order to avoid stainless steel rust, please pay attention to the following: 1, the surface of stainless steel valves to regular cleaning swab, remove attachments, remove rust external factors.
2, coastal areas to use 316, 316 l stainless steel material, 316, 316 l material corrosion resistance to sea water.
3, some of the chemical composition of stainless steel valves on the market can not meet the corresponding national standards, amounted to less than 304 material requirements, which will cause rust, which requires users to choose reputable manufacturer product carefully.