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Do stainless steel solenoid valves rust

Stainless steel valves, our most direct intuition is that stainless steel valves are never rusty. If we buy stainless steel valves, it must be a matter of material. In fact, stainless steel will rust under certain conditions. Stainless steel has the ability to resist atmospheric oxidation - that is, rust - free, and also has the ability to resist corrosion in the medium containing acid, alkali and salt - that is, corrosion resistance. But its corrosion resistance is changed with the chemical composition, service conditions and environmental media types of the steel itself. For example, 304 valves, in a dry and clean atmosphere, have excellent corrosion resistance, but move it to the seaside, and in the sea fog containing a large amount of salt, it will soon rust; and the 316 valve is good. Therefore, not any stainless steel can be corroded and rust free under any environment.
So why stainless steel valves are rusty? To analyze the reason, the surface of the stainless steel valve is a thin, sturdy, stable chromium rich oxide film (protective film), which prevents the continuous infiltration and oxidation of oxygen atoms, and has the ability to resist corrosion. Once the film is destroyed for some reason, the oxygen atoms in the air or in the liquid are constantly infiltrated, or the iron atoms in the metal are constantly separated out to form a loose iron oxide, and the metal surface is constantly corroded. As a result, stainless steel is rusty. High pressure solenoid valve
What causes the destruction of the film on the surface of stainless steel?
1, the surface of stainless steel valves is deposited with the attachment of dust or heterogeneous metal particles containing other metal elements. In wet air, the condensate between the attachment and the stainless steel is condensed into a micro battery, which causes the electrochemical reaction, the protective film is damaged, and it is called electrochemical corrosion.
2, the surface of stainless steel valves adhered to organic juice (such as melon, soup, phlegm, etc.), in the presence of water and oxygen, organic acids, long time corrosion of the organic acid on the metal surface.
3. The surface of stainless steel valves adheres to acid, alkali and salt substances, such as alkaline water and lime water splashing, which cause localized corrosion.
4. In the polluted air (such as the atmosphere containing a large amount of sulphide, carbon oxide and nitrogen oxide), it condenses water to form sulfuric acid, nitric acid and acetic acid solution, causing chemical corrosion.
All above can cause rust on the surface of stainless steel. To avoid rust, please pay attention to the following items:
1, the surface of stainless steel valves must be cleaned and scrubbed regularly to remove attachments and eliminate external factors that cause corrosion. Vacuum solenoid valve
2, seashore area should use 316 material stainless steel, 316 material can resist seawater corrosion.
3, the chemical composition of some stainless steel valves in the market can not meet the corresponding national standards, less than 304 of the material requirements. It will also cause rust, which requires users to choose products from Shanghai Kai faction.

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