Bearings
Lubrication
Lubrication is essential for any bearing application. There are two methods of lubrication: using grease or using oil. A lubricant primarily has three functions:
- Prevent or try to reduce wear
- Keeping the friction in the bearing at a low level
- Preventing the ingress of dirt
Other functions of lubrication are: protection against corrosion, removal of heat and wear particles and support of the sealing effect. Grease is used in most cases for the lubrication of bearings under normal conditions. Grease has the advantage over oil that it can be more easily retained in the bearing. Sealed bearings are supplied with grease as standard from the factory. The amount is then about 30% of the free space in the bearing. More grease is not necessary, because then it is detrimental to the proper functioning of the bearing because the operating temperature then rises faster.
Greases
Lubricating greases consist of mineral or synthetic oils. The standard ball bearing grease is made on the basis of lithium soap that has an operating temperature of -30°C to +110°C. Depending on the working conditions of the bearings, other lubricants are of course also possible, such as at very low or very high temperatures, at extreme speeds or heavy loads.
Oil lubrication is often used in applications that already have oil lubrication, where a centralized lubrication system is used or where oil is used as a coolant. Oil lubrication is also often used when grease lubrication is no longer permitted due to high speeds or high operating temperatures.