Causes of rust in slewing bearings and rust prevention method
Causes of rust in slewing bearings and rust prevention method
Slewing bearing is a kind of large bearing with special structure. It is widely used in many construction machinery or equipment platforms. If the bearing is stored or used improperly, it may cause rust, which will affect the use effect. Today, we will introduce to you the reasons for the rust of the slewing bearing and the commonly used anti-rust methods.
1. The cause of rust
1) The relative humidity is too high
The relative humidity we often say refers to the ratio of the water vapor content in the air to the saturated water vapor content of the air at the same temperature, usually expressed as a percentage. The relative humidity is proportional to the humidity in the air. The higher the relative humidity, the faster the metal corrosion. In general, the critical relative humidity of steel is 70%.
2) The temperature increases to speed up the chemical reaction
When the air is humid, the metal will interact with the oxygen and water in it. Above the critical temperature, condensation will form on the metal surface, resulting in corrosion. If the relative humidity reaches the critical humidity of the metal, the effect of temperature will change. Obviously, as the temperature increases, the reaction speed continues to accelerate, resulting in corrosion of the bearing.
3) The effect of oxygen
Oxygen can be dissolved in water during the storage process of the bearing. The corrosion phenomenon of oxygen concentration difference is relatively common, and the solubility of different parts will change. When the bearings are stacked, the oxygen is insufficiently inflated in the middle of the overlapping surface, the concentration in the water is low, the oxygen at the edge is sufficient, and the concentration in the water is high, which will cause rust around the edge of the overlapping surface.
4) Effects of pollutants in the atmosphere
The atmosphere contains various pollutants, such as carbon dioxide, nitrogen oxides, carbon dioxide and other gases and solid dust. These pollutants will condense on the metal surface together with the water mist in the air, and dissolve in water to produce the following results: various non-metallic oxides dissolve in water to become acids, which will destroy the passive film on the metal surface and cause rust.
2. Anti-rust method
1) Immersion method
After cleaning the slewing bearing, it is immersed in a solution of 5% sodium nitrite and 0.6% sodium carbonate. The anti-rust effect is good, but many anti-rust tanks and other equipment are required, which take up a lot of space and are inconvenient to manage.
2)Spray method
Use filtered compressed air with a pressure of about 0.7Mpa to spray in a clean air place. The spray method is suitable for solvent-diluted anti-rust oil or thin-layer anti-rust oil, and fire protection and labor protection measures are required.
3) Use special rust remover for bearings
The special rust remover for bearings is a rust removal product that can remove rust but does not damage the material of parts. After rust removal, it can maintain the original color of the product metal.
The above is the reason for the rust of the slewing bearing and the commonly used anti-rust treatment methods. I hope to provide you with help in the preservation or use of the bearing. Luoyang Hengguan Bearing Technology Co., Ltd. has been deeply involved in the field of slewing bearing/slewing bearing for many years. If you have other questions or related needs, you can leave a message or contact us by phone.
