How much do you know about the properties of 316L stainless steel pipes

316L stainless steel welded pipes are widely used in environments with moisture and corrosive substances (such as the sea), and are extensively employed in industrial pipelines for transportation in industries like petroleum, chemical engineering, medicine, food, light industry, mechanical instruments, etc., as well as in mechanical structural components. The reason is that the welded 316L stainless steel pipes have strong corrosion resistance. Why do 316L stainless steel welded pipes have high corrosion resistance? 

Stainless steel can also rust under certain conditions. Although 316L stainless steel has natural resistance to atmospheric oxidation, which means it does not rust, it can also resist corrosion in environments containing acids, alkalis, salts, etc., which is its corrosion resistance. The corrosion resistance of 316L stainless steel varies with changes in chemical composition, physical state, working conditions and environmental media. 

For instance, in a dry and clean atmosphere, the corrosion resistance of 304 stainless steel is definitely good. However, once it reaches an area near the coast, due to the high concentration of smoke, it is prone to rusting. But 316 stainless steel is better. Therefore, stainless steel is not resistant to corrosion and rusting in any environment. 

The surface of the 304 stainless steel rod is covered with a very thin yet stable and fine dense chromium oxide film (protective film), which can prevent oxygen atoms from penetrating and oxidizing the base material. This is the reason for its anti-corrosion performance. However, for some reasons, this film will continue to be damaged. Oxygen atoms in the air or liquid will continue to separate, causing loose iron oxide and rusting on the surface of the stainless steel. 

The surface layer of 316L stainless steel pipes will also react with oxygen. However, due to its high chromium content, and because the key to the corrosion resistance of 316L stainless steel pipes lies in the chromium content, when the chromium content of 316L stainless steel exceeds 10.5%, the corrosion resistance of 316L stainless steel will be greatly enhanced. 

When the chromium content of 316L stainless steel exceeds 10.5%, the corrosion resistance of 316L stainless steel will be significantly enhanced. When conducting research on alloy treatment for stainless steel using chromium elements, the type of oxide film formed on the surface of the stainless steel material was changed to be similar to the surface oxide film formed on pure chromium metal. This oxide film can better protect the surface of the stainless steel and prevent further oxidation. 

This oxide film is extremely thin. Our teachers can choose to look through it to see the original natural luster of the stainless steel material surface, giving the stainless steel pipe a surface that is... In addition, if the surface layer is damaged, the damaged part that exposes the stainless steel surface will undergo changes with the atmospheric environment. The chromium element will automatically provide assistance for the stainless steel material surface to be able to conduct self-protection and repair, allowing the stainless steel surface to need to start forming a passivation film again, continuing to protect and escort the stainless steel. 

All stainless steel pipes share a common characteristic, that is, the chromium content is above 10.5%. The steel types related to the construction application fields usually only have six varieties. They all contain 17-22% chromium, and the basic steel types also contain nickel. The 316L stainless steel industrial welded pipes with molybdenum can further improve the atmospheric corrosion resistance, especially the corrosion resistance in the presence of chloride ions. This is the reason why the 316L stainless steel industrial welded pipes have strong corrosion resistance.