Selection skills about bearing grease
The selection of bearing grease must be considered from the following aspects:
1, rust resistance
The grease used in the bearing must have anti-rust effect, and the anti-rust agent is best insoluble in water. The grease should have good adhesion and form an oil film on the surface of the steel.
2. Mechanical stability
Grease becomes soft during machining, 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 enough, the structure of the grease soap will collapse mechanically in the operation process, resulting in the destruction of the grease, thus losing the lubrication effect.
3, oil seal,
Oil seal is a necessary barrier to protect bearings and lubricants from foreign pollution. In the process of bearing operation, no matter debris or moisture can penetrate into the bearing to prevent damage to it.
Correct installation and maintenance is an important factor in the maximum service life of bearings. 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 contaminants and moisture, and ensure that they are properly installed and lubricated. Therefore, the design of bearing alignment, the condition of oil seal, the type and lubrication cycle of lubricant, and even special maintenance all play the same and important role.
4. Mix oil
Never mix incompatible oils. If two incompatible oils are mixed, their consistency will usually become soft, and eventually may cause damage to bearings due to easy loss of oil. If you do not know what kind of grease the bearing originally uses, you must first thoroughly remove the old grease inside and outside the bearing before adding new grease.
5. Classification of grease
Mainly according to temperature and working conditions: grease can be classified according to their allowable working temperature, grease consistency and lubrication ability are affected by the working temperature, bearings operating at a certain temperature must choose grease with correct consistency and good lubrication effect at the same temperature. Oils and fats are manufactured in different operating temperature ranges and can be roughly divided into low, medium and high temperature oils and fats. At the same time, there is a class of oil called extrusion resistance or extrusion resistance and add molybdenum disulfide, at the same time, in which additives are added to strengthen the lubricating oil film strength.
6. Important factors in selecting grease
If the wrong selection of grease, all the preventive measures of bearings are futile, choose a grease, its base oil viscosity at the working temperature is able to provide enough lubrication effect is very important, viscosity is mainly affected by temperature, it decreases with the rise of temperature, when the temperature drops it rises. Therefore, it is necessary to know the base oil viscosity at operating temperature. Machinery manufacturers usually specify certain greases, however most standard greases are suitable for a wide range of applications.
The following are several important factors in the selection of grease: type of machinery; Bearing type and size; Working temperature; Workload; Speed range; Working conditions, such as vibration and spindle direction is horizontal or vertical; Cooling condition; Sealing effect; Peripheral environment. I'm sure you understand a lot here. Let's make the right choice.