Reasons for Rust of Stainless Steel Valves and Solution for Anti-rust

I. Reasons for Rust of Stainless Steel Valves

To test whether stainless steel valves will rust, we can put the same valves in different environments to verify and compare. Generally speaking, if stainless steel valves are placed in relatively dry environments, after long time, the valves are not only as good as new, but also not rusty. But if the valves are placed in seawater containing a lot of salt, they will rust in a few days. Therefore, the corrosion resistance and stainless of stainless steel valves also need to be limited by the use environment. In addition, from the characteristics of stainless steel valve itself, it is stainless because there is a layer of chromium-rich oxide film on its surface to prevent particles such as oxygen atoms from invading and damaging objects, which makes it stainless. But when the film is destroyed by environmental factors, as oxygen atoms enter and iron ions free, stainless steel valve will produce rust.

The destruction of stainless steel valve surface film causes many reasons for rust. Some of them are electrochemical reactions with other metal elements or particles. At the same time, with the help of moist air as a medium, a micro battery cycle is formed, which makes stainless steel surface rusty. It can also be exposed to corrosive liquids such as strong acid and strong alkali, and so on. In order to prevent stainless steel valve from rusting, we should also pay attention to the cleaning of objects in daily use and keep the surface of the valve clean.

Rust of valve in site (Attached not stainless steel valve, just steel valve for show rust of valve)

2. Solution/measure for rusting of stainless steel valves

So how to ensure that the metal surface is permanently bright and not rusted? The professional and technical personnel of Sangong Flow Control Co., Limitd. suggest:

1. The surface of decorative stainless steel must be cleaned and scrubbed regularly to remove the attachments and eliminate the external factors causing the modification.

2. Coastal area should use 316(CF8M) stainless steel or similar better 316L(CF3M) A995 4A(2205) 5A.. , These austenitic stainless steel or Duplex steel  material can resist seawater corrosion.

3. The chemical composition of some stainless steel pipes on the market can not meet the corresponding national standards, and can not meet the material requirements of 304.There are many products have only 8% ni or a little lower Ni. precent than standard. Therefore, it will also cause rust, which requires users to carefully select the right product from reputable manufacturers and pay attention to construction in order to prevent scratches and pollutants attachment during construction. However, with the extension of time, the residual paste should be cleaned according to the service life of the paste. When the paste is removed after construction, the surface should be washed, and special stainless steel tools should be used. When cleaning common steel tools, in order to prevent the iron chips from adhering, it should be cleaned. Attention should be paid not to contact the surface of stainless steel with highly corrosive magnetism and luxurious cleaning stones. Washing should be done immediately if have contact. After the completion of construction, neutral detergents or water  should be applied to wash any cement, fly ash, etc. attached to the surface.

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