The selection of bearing lubricating grease is directly related to the stable operation of the equipment. In order to better utilize the best condition of the bearings, the selection of bearing lubricating grease must be considered from the following aspects:
1. Rust prevention performance
The grease used in bearings must have a rust preventive effect, and the rust inhibitor should preferably be insoluble in water. The grease should have good adhesion and can form an oil film on the surface of the steel.
2. Mechanical stability
Oil and grease can become soft during mechanical processing, leading to leakage. During normal operation, grease will be thrown into the bearing by the bearing seat. If the mechanical stability of the grease is not sufficient, the soap structure of the grease will undergo mechanical disintegration during operation, causing the grease to be damaged and losing its lubrication effect.
3. Oil seal
Oil seals are necessary barriers to protect bearings and lubricants from external pollution. During the operation of bearings, no debris or moisture can penetrate into the bearing to prevent damage.
Proper installation and maintenance are important factors in maximizing the bearing's maximum service life. At the same time, attention must be paid to the cleanliness of bearings, the correctness of bearing selection, and the selection of appropriate installation and maintenance tools. In addition, bearings must be protected from contamination by pollutants and moisture, and ensure proper installation and lubrication. Therefore, the design of bearing arrangements, the condition of oil seals, the type and cycle of lubricants, and even specialized maintenance all play the same but important role.
4. Mixed grease
Never mix incompatible oils and fats. If two incompatible oils and fats are mixed, their consistency will usually become soft, and ultimately, the bearing may be damaged due to the easy loss of oil and grease. If you do not know which type of grease the bearing originally used, you must thoroughly remove the old grease inside and outside the bearing before adding new grease.
5. Classification of fats and oils
Mainly distinguished by temperature and working conditions: greases can be classified based on their allowable working temperature. The consistency and lubrication ability of greases are affected by the working temperature. Bearings operating at a certain temperature must choose a grease that has the correct consistency and good lubrication effect at the same temperature. Oils are manufactured in different operating temperature ranges and can be roughly divided into low temperature, medium temperature, and high temperature oils. At the same time, there is a type of grease called anti extrusion or anti extrusion with the addition of molybdenum disulfide, and additives are added to enhance the strength of the lubricating oil film.
6. Important factors in selecting oils and fats
If the wrong choice of grease is made, all measures to prevent bearings are also futile. Choosing a grease whose base oil viscosity can provide sufficient lubrication effect at operating temperature is crucial. The viscosity is mainly affected by temperature, and it decreases with increasing temperature. When the temperature decreases, it increases. Therefore, it is necessary to know the viscosity of the base oil at operating temperature. Machinery manufacturers usually specify the use of a certain type of grease, but most standard lubricants have a wide range of applications.
