Views: 0 Author: Site Editor Publish Time: 2025-07-29 Origin: Site
One of the important advantages of stainless steel pipes, which makes them widely used, is their corrosion resistance. However, the corrosion resistance of different types of stainless steel pipes varies. The following introduces several types of stainless steel pipes with strong corrosion resistance.
The 300 series stainless steel pipes are a category with strong corrosion resistance, among which the 304 stainless steel pipes are the most common. They contain about 18% chromium and 8% nickel. The chromium element forms a dense chromium oxide passive film on the surface of the pipes, which can effectively prevent oxygen and moisture from eroding the internal metal. They perform well in general atmospheric environments, fresh water and mild corrosive media, and are often used in food processing, architectural decoration and other fields.
The 316 stainless steel pipes, on the basis of 304, add 2%-3% molybdenum, which further improves their corrosion resistance. Especially in environments containing chloride ions, such as seawater and chemical waste liquid, their resistance to pitting and crevice corrosion is significantly better than that of 304 stainless steel pipes. Therefore, they are widely used in marine engineering, chemical equipment and other fields.
The 200 series stainless steel pipes use manganese to replace part of nickel, so their cost is relatively low. Although their overall corrosion resistance is not as good as that of the 300 series, they can still function in some dry environments with low corrosivity, such as interior decoration, ordinary structural brackets and other scenarios. However, in humid or corrosive environments, their corrosion resistance performance is poor, so caution should be exercised when using them.
The 400 series stainless steel pipes belong to ferritic and martensitic stainless steels, with a relatively high chromium content, usually between 11%-17%, but no nickel. Among them, the 430 stainless steel pipes have certain corrosion resistance, can form a passive film in the atmospheric environment, and can be used in household appliances, decorative parts, etc. But compared with the 300 series, their corrosion resistance is weak in environments with strong corrosivity such as acid and alkali, and they are easily eroded.
Duplex stainless steel pipes combine the advantages of austenitic and ferritic stainless steels. They have a chromium content of 21%-27%, a nickel content of 4%-7%, and also contain elements such as molybdenum and nitrogen. This composition not only gives them high strength, but also excellent corrosion resistance. Especially in chloride environments, they have strong resistance to stress corrosion cracking and pitting, and are suitable for harsh corrosive environments such as petrochemical industry and seawater treatment.
Super austenitic stainless steel pipes are developed on the basis of the 300 series, containing higher contents of chromium, nickel, molybdenum and other alloying elements, and their corrosion resistance is excellent. They can resist a variety of strong corrosive media, such as sulfuric acid, phosphoric acid, nitric acid, etc., and can remain stable in extremely harsh corrosive environments. They are often used in high-end chemical industry, medicine and other fields with extremely high requirements for corrosion resistance.
Different types of stainless steel pipes have different focuses in corrosion resistance due to their different compositions. When selecting, it is necessary to choose the appropriate stainless steel pipe according to the specific use environment, such as medium type, temperature, pressure and other factors, to ensure that it can play a long-term role in corrosion resistance.
