Customers usually believe that stainless steel centrifugal pumps will not rust, and rust is not a stainless steel pump. When brown rust spots (spots) appear on the surface of the stainless steel pump, the customer believes that there is a problem with the steel. In fact, this is a misconception about a lack of understanding of stainless steel. In some cases, stainless steel can also rust. There are many forms of damage to such surface facial mask. The following are common phenomena in daily life:
1. The surface of stainless steel contains dust or other metal particles attached to other metal elements. In humid air, the condensed water between the attached material and stainless steel connects the two to form a miniature battery, leading to a chemical reaction that generates electricity. The destruction of the protective film is called electrochemical corrosion.
As shown in Figure 2, in the presence of water and oxygen, the surface of stainless steel adheres to organic juices (such as melons, noodle soup, glutinous rice, etc.), forming organic acids that corrode the metal surface for a long time.
3. The surface of stainless steel adheres to acid, alkali, and salt substances (such as alkaline water and lime water splashed onto the wall), causing local corrosion.
4. In polluted air (such as atmospheres containing large amounts of sulfides, carbon oxides, and nitrogen oxides), liquid points of sulfuric acid, nitric acid, and acetic acid can form in the presence of condensed water, leading to chemical corrosion.
All of the above situations can cause corrosion and rusting of the protective film on the surface of stainless steel.
Therefore, to ensure that the metal surface is bright and does not rust, we recommend:
1. The surface of decorative stainless steel must be regularly cleaned and scrubbed to remove deposits and eliminate external factors that cause modification.
2. Coastal areas should use 316 stainless steel, which can resist seawater corrosion.
3. Some chemical components of stainless steel pipes on the market cannot meet the corresponding national standards and cannot meet the requirements of 304 materials. Therefore, it can also cause rusting, which requires users to carefully select products from reputable manufacturers.