Aballbearingisatypeofroll-elementbearingthatusesballstomaintaintheseparationbetweenthebearingraces.
Thepurposeofaballbearingistoreducerotationalfrictionandsupportradialandaxialloads.
Itachievesthisbyusingatleasttworacestocontaintheballsandtransmittheloadsthroughtheballs.
Inmostapplications, oneraceisstationaryandtheotherisattachedtotherotatingassembly (m.sh., ahuborshaft).
Asoneofthebearingracesrotatesitcausestheballstorotateaswell.Becausetheballsarerolltheyhaveamuchlowercoefficientoffrictionthaniftwoflatsurfaceswereslidingagainsteachother.
Ballbearingstendtohavelowerloadcapacityfortheirsizethanotherkindsofroll-elementbearingsduetothesmallercontactareabetweentheballsandraces.
Mar sin féin, hecantoleratesomemisalignmentoftheinnerandouterraces.
