When the stainless steel tube surface appear brown rusty spot (or points), big surprised: people think "stainless steel is not rusty, rust is not stainless steel, is likely to be the problem of steel". In fact, this is a one-sided erroneous view of the lack of understanding of stainless steel. Xin cangtai technology simply illustrates the reason: stainless steel can rust under certain conditions.

       Stainless steel has the ability to resist atmospheric oxidation - that is, non-rust, and also has the ability to resist corrosion in the medium of acid, alkali and salt, the corrosion resistance. But the size of the corrosion resistance is changed by the chemical composition of the steel itself, the addition state, the use condition and the type of environmental media. As 304 steel tube, in dry, clean atmosphere, have absolute good corrosion resistance, but it will be moved to the coastal areas, in contains a great deal of sea salt fog, will soon be rusty; And 316 steel pipes performed well. Therefore, not any kind of stainless steel, can resist corrosion in any environment, not rust.

       There are many forms of damage to the surface membrane.

Stainless steel is formed on the surface of a layer of a very thin and fine and stable solid rich chromium oxide film (protective film), prevent oxygen to infiltration, continue to oxidation, and ability to resist corrosion. Once you have some reason, the film has been continuously destroyed and air or oxygen atoms in the liquid iron atoms will constantly infiltration or metal separation out unceasingly, forming loose iron oxide, metal surface are also constantly rust. This surface membrane is destroyed in many forms, and the common ones are:

1, deposited on the surface of the stainless steel contain other metal elements of attachments, or heterogeneous metal particles of dust in the humid air, attachments and stainless steel, the condensed water between the both together as a micro battery, triggers the electrochemical reaction, protective film is damaged, to call the electrochemical corrosion.

2, stainless steel surface adhesion organic fluids (such as melon seeds, noodle soup, sputum, etc.), under the condition of water is oxygen, organic acid, organic acid to for a long time and are on the surface of the metal corrosion.

3,Stainless steel surface adhesion contains acid, alkali, salt material (for example, the alkali water that decorates the wall, the lime water spray), cause local corrosion.

4, where there is pollution in the air (e.g., contains a lot of sulfur, carbon oxide, atmospheric nitrous oxide), encounter condensation water, formation of sulfuric acid, nitric acid, acetic acid, liquid, chemical corrosion.

How do you ensure that the surface of the metal is permanently bright and not corroded?

1,All of these conditions can cause corrosion of stainless steel surface protection film. So, in order to make sure that the surface of the metal is permanently bright and not corroded, the technology suggests how to use stainless steel products:

2,The surface of decorative stainless steel must be cleaned and cleaned frequently, removing fixtures and removing external factors that cause modification.

The sea area should use 316 material stainless steel, 316 material can resist seawater corrosion.

3,There are some stainless steel pipe chemicals in the market that do not meet the national standards, which are less than 304. It also causes rust, which requires the user to carefully select products from reputable manufacturers.