The quality of the selected bearing grease is directly related to the stable operation of the equipment. To optimize bearing performance, the selection of bearing grease must take the following aspects into consideration:

1. Rust Prevention Performance

The grease used in the bearing must have a rust prevention effect, and the rust inhibitor should preferably be insoluble in water. The grease should have good adhesion and be able to form an oil film on the steel surface.

2. Mechanical Stability

Grease may soften during machining, leading to leakage. During normal operation, grease is slung from the bearing housing into the bearing. If the mechanical stability of the grease is insufficient, the soap structure of the grease may undergo mechanical disintegration during operation, causing the grease to break down and lose its lubricating effect.

3. Oil Seals

Oil seals are a necessary barrier to protect the bearing and lubricant from external contamination. During bearing operation, neither debris nor moisture should be able to penetrate the bearing to prevent damage.

Correct installation and maintenance are important factors for maximizing bearing service life. At the same time, attention must be paid to bearing cleanliness, correct bearing selection, and the use of appropriate installation and maintenance tools. In addition, bearings must be protected from contamination by pollutants and moisture and must be correctly installed and lubricated. Therefore, the design of the bearing arrangement, the condition of the oil seal, the type of lubricant and lubrication cycle, and even specialized maintenance all play the same important role.

4. Grease Mixing

Never mix incompatible greases. If two incompatible greases are mixed, their consistency usually softens, which may eventually lead to bearing damage due to grease loss. If you do not know which lubricating grease was originally used in the bearing, the old grease must be completely removed from inside and outside the bearing before adding new grease.

5. Classification of Greases

Classification is mainly based on temperature and operating conditions: Greases can be classified according to their allowable operating temperature. The consistency and lubricating ability of grease are affected by operating temperature. Bearings operating at a certain temperature must use a grease with the correct consistency and good lubricating effect at that temperature. Greases are manufactured for different operating temperature ranges and can be broadly divided into low-temperature, medium-temperature, and high-temperature greases. Additionally, there is a category of greases known as anti-extrusion or anti-extrusion with molybdenum disulfide, which contain additives to enhance the strength of the lubricating oil film.

6. Important Factors in Grease Selection

If the wrong grease is selected, all measures to prevent bearing failure will be futile. It is important to select a grease whose base oil viscosity can provide sufficient lubrication at the operating temperature. Viscosity is mainly affected by temperature; it decreases as temperature rises and increases as temperature falls. Therefore, the base oil viscosity at the operating temperature must be known. Machinery manufacturers usually specify a certain type of grease; however, most standard lubricating greases have a wide range of applications.