Rolling bearings are also known as “anti-friction bearings”, but of course, some frictional losses occur in the bearing. One contributing factor to rolling friction in a bearing is the result of elastic deformation of the rolling elements and raceways under load. Other sources include, but are not limited to, the sliding friction that occurs between the rolling elements and cage, flanges and guide rings, and between seals and their counterface. Friction in the lubricant also contributes to the total frictional moment. The frictional moment of SKF rolling bearings can be calculated (→ Friction).
In general, ball bearings have a lower frictional moment than roller bearings. If very low friction is an essential requirement, SKF Energy Efficient (E2) bearings should be considered. The frictional moment in SKF E2 bearings is at least 30% lower than a similar-sized SKF standard bearing. SKF E2 bearings are available for several bearing types:
- single row deep groove ball bearings
- Y-bearings (insert bearings)
- double row angular contact ball bearings
- single row tapered roller bearings
- cylindrical roller bearings