Axial & Radial Internal Clearance testing for bearings
can be moved in relation to the other in the radial direction (radial internal clearance) or in the axial direction (axial internal clearance). Too little or too much internal clearance will significantly influence factors such as heat, vibration, noise and fatigue life. In extreme applications that produce high or low temperatures, this clearance needs to be considered in the overall design to compensate for thermal expansion and contraction of housings and shafts. Bearings having an internal clearance other than Normal are identified by the suffixes C1 to C5.