Full definition
Tolerance system between the bearing and its shaft or housing that determines whether the fit is interference (tight) or clearance (sliding). Inner ring typically uses interference fit on shaft: j5, k5, m5 or n6 depending on load and speed. Outer ring uses sliding or slight interference fit in housing: H7, J7, K7. ISO 286 standard. Incorrect fits are a frequent cause of premature bearing failure through creep or fretting corrosion.