Why does the stainless steel heating rod rust?
Why is the stainless steel electric tubular heater rusted? When the surface of the stainless steel electric heating elment has brown rust spots (points), people are very surprised: "The stainless steel is not rusted, the rust is not stainless steel, it may be the heating tube manufacturer. The material replaces stainless steel." actually not. Stainless steel will also rust under certain conditions. Stainless steel has the ability to resist atmospheric oxidation, that is, rust, and also has the ability to resist corrosion in a medium containing acid, alkali, and salt, that is, corrosion resistance. However, the amount of corrosion resistance varies with the chemical composition of the steel itself, the state of each other, the conditions of use, and the type of environmental medium. For example, 304 steel pipe has absolutely excellent rust resistance in a dry and clean atmosphere, but it is moved to the coastal area, and it will soon rust in sea fog containing a lot of salt; while 316 steel pipe will perform. good. Therefore, it is not any kind of stainless steel, it can resist corrosion and rust in any environment.
Stainless steel is a very thin and strong and stable chromium-rich oxide film (protective film) formed on the surface to prevent oxygen atoms from continuing to infiltrate and continue to oxidize, thereby obtaining corrosion resistance. For some reason, the film is constantly destroyed, the oxygen atoms in the air or liquid will continuously infiltrate or the iron atoms in the metal will continuously separate out, forming loose iron oxide, and the metal surface will be continuously Corroded.
In order to ensure that the metal surface is permanently bright and not rusted, we recommend that the surface of the stainless steel electric heating tube must be cleaned and scrubbed frequently to remove the deposits and eliminate external factors that cause corrosion. The 316 material is used in the coastal area, and the 316 material is resistant to seawater corrosion.
Electric heating tubular heater use precautions
1. When the electric heating rod is used to heat the easily melted metal or solid nitrate, paraffin, asphalt and other materials, the heating material should be melted first. At this time, the external voltage of the electric heating tube can be reduced, and then the rated voltage is restored after the melting is completed. In addition, when the electric heating pipe heats a substance that is prone to explosion accidents such as nitrate, it is necessary to fully consider safety measures.
2. When the electric heating tubular is used for air heating, pay attention to the uniform arrangement of the electric heating tubes. The advantage of this is to ensure that the electric heating tube has a relatively sufficient and uniform heat dissipation space, and as much as possible to ensure the fluidity of the air and improve the heating of the electric heating tube. effectiveness.
3. The gap inside the electric heating element is filled with magnesia oxide. The magnesia sand at the outlet end of the electric heating element is easily contaminated by the infiltration of impurities and moisture. Therefore, pay attention to the state of the outlet end of the electric heating tube during operation to avoid leakage. accident.