Stainless steel butterfly valves rely on a very thin, strong, fine and stable chromium-rich oxide film (protective film) formed on its surface to prevent the continued infiltration and oxidation of oxygen atoms, thereby obtaining the ability to resist rust. Once for some reason, this film is constantly damaged, oxygen atoms in the air or liquid will continue to infiltrate or iron atoms in the metal will continue to separate out, forming loose iron oxide, and the metal surface will continue to rust.
Advantages of stainless steel butterfly valves:
Stainless steel butterfly valves can resist oxidation in the atmosphere and are corrosion-resistant in acid, alkali and salt media, so all-stainless steel butterfly valves have the characteristics of wear resistance and corrosion resistance. These characteristics can fully reflect the advantages of stainless steel materials, but there is still the possibility of rust in some special environmental media. Here are a few:
1. Organic juice (such as vegetables, noodle soup, sputum, etc.) adheres to the surface of stainless steel butterfly valves. In the presence of water and oxygen, organic acids are formed, and organic acids corrode the metal surface for a long time.
2. The surface of the stainless steel butterfly valve is covered with dust containing other metal elements or foreign metal particles. In the humid air, the condensed water between the attachment and the stainless steel connects the two into a micro-battery, triggering an electrochemical reaction, and the protective film is damaged, which is called electrochemical corrosion.
3. The surface of the stainless steel butterfly valve adheres to substances containing acids, alkalis, and salts (such as alkaline water and lime water splashing on the wall decoration), causing local corrosion.
4. In polluted air (such as an atmosphere containing a large amount of sulfides, carbon oxides, and nitrogen oxides), the stainless steel butterfly valve encounters condensed water, forming sulfuric acid, nitric acid, and acetic acid liquid points, causing chemical corrosion. The above situations can cause the destruction of the protective film on the surface of the stainless steel and cause rust.
In order to ensure that the stainless steel does not rust, it is recommended to clean and scrub the surface of the decorative stainless steel frequently, remove the attachments, and eliminate the external factors that cause the modification. Reasonably choose the stainless steel material suitable for your working conditions.