What are the causes of oxidation in thin-walled stainless steel pipes

Thin-walled stainless steel pipes possess oxidation resistance due to a very thin but exceptionally strong and dense chromium-rich oxide protective film on their surface, which prevents oxygen atoms from penetrating the pipe. However, under certain circumstances, this film is continuously damaged, allowing oxygen atoms from the air or liquid to continuously penetrate, or allowing iron atoms from within the pipe to continuously precipitate, forming loose iron oxide. This leads to continuous oxidation of the pipe's surface. When oxidation occurs on the pipe surface, oxides accumulate, and once a certain scale is reached, further oxidation slows significantly. So, what are the causes of oxidation in thin-walled stainless steel pipes?

1. Manufacturing process of thin-walled stainless steel pipes.

This is one of the reasons for oxidation in thin-walled stainless steel pipes. From a manufacturing process and product characteristics perspective, forming a thin oxide film on the product surface is a fundamental process to prevent oxidation and is one of the main characteristics that distinguishes stainless steel from other steel products. However, due to insufficient or negligent production processes, when the oxide film is incomplete or discontinuous, oxygen in the air directly reacts with some elements in the thin-walled stainless steel pipe in a redox reaction, resulting in surface oxidation.

2. Composition Ratio of Thin-Walled Stainless Steel Pipes.

Some manufacturers, to reduce production costs, reduce the proportion of important elements such as chromium and nickel, while increasing the content of other elements, such as carbon. This production practice, which does not strictly adhere to the composition ratios according to the type and characteristics of the thin-walled stainless steel pipe, not only significantly reduces product quality but also affects the product's appearance and oxidation resistance. For example, when the chromium content of 304 stainless steel pipe is insufficient, it not only affects the product's corrosion resistance and formability but also poses a potential quality risk when used in industrial applications.

3. Human-caused oxidation in thin-walled stainless steel pipes.

This is also one of the common causes of oxidation encountered by consumers when using thin-walled stainless steel pipes. Improper operation during the use and maintenance of thin-walled stainless steel pipes, especially in products used in the food and chemical equipment industries, increases the likelihood of human-caused oxidation. For human-caused oxidation, it is essential to have correct product usage knowledge and to perform regular, reasonable, and effective maintenance.

The above are some of the reasons for oxidation in thin-walled stainless steel pipes. These include: production processes; reducing anti-oxidation elements such as chromium and nickel while increasing carbon content; and improper use and maintenance. Therefore, manufacturers must pay attention to the ingredient ratios during the production of thin-walled stainless steel pipes; secondly, they must choose appropriate production processes to prevent oxidation; and thirdly, they must address issues related to use and maintenance, ensuring correct use and regular upkeep.