Why corrosion resistant stainless steel flange? All metal flange and atmospheric oxygen reaction, a layer of oxide film on the surface. Unfortunately, in the ordinary carbon steel on the oxidation of formation of iron oxide to continue to make a thorough, kept expanding rust, eventually forming holes. Can use paint or resistant to oxidation of the metal (for example, zinc, chromium and nickel) to ensure that the surface of the carbon steel metal plating, however, as most people know, the protection is only a thin film on the stainless steel flange. If the protective layer is severely damaged, the following flange began to rust.
The corrosion resistance of the stainless steel flange depends on chrome, but because of the chromium is one part of the steel, so the protection method is not the same. In the chromium content of 11.7% or more, atmospheric corrosion resistance of steel increased significantly, but the chromium content is higher, although still can improve the corrosion resistance, but not obvious. Reason is that with chromium alloying of steel processing, change the type of surface oxide became similar to that of pure chromium oxide is formed on the metal surface. This tight adhesion of the rich chromium oxide protection table surface, to prevent further oxidation. This kind of extremely thin oxide layer, you can see on the surface of the steel through natural luster, make the surface of the stainless steel flange has a unique.
Source: Zhejiang Yaang Pipe Industry Co., Limited (www.yaang.com)