Technical>Bearing Internal Clearance
Bearing Internal Clearance

Bearing internal clearance is defined as the total distance through which one bearing ring can be moved relative to the other in the radial direction (radial internal clearance) or in the axial direction (axial internal clearance).

 ● Internal Clearances of deep groove ball bearings Deep groove ball bearings having an internal clearance other than Normal are identified by the suffixes C2 to C5. Meanwhile the axial internal clearances will vary accordingly. Following diagrams show the relationship between radial internal clearance and axial internal clearance for four series of deep groove ball bearing.

Radial Internal Clearance Δr and Axial Internal Clearance Δa in Single-Row Deep Groove Ball Bearings

Note: Please check the charts in next page for the relationship of radial clearance and axial clearance of deep goove ball bearings.

● Internal clearance of tapered roller bearing clearance
In tapered roller bearings, internal clearance is usually defined as a specific amount of either end play or preload. Establishing this clearance, or setting, at the time of assembly is an inherent advantage of tapered roller bearings. Unlike deep groove ball bearing, tapered roller bearings do not rely strictly on housing or shaft fits to obtain a certain bearing setting. One race can be moved axially relative to the other to obtain the desired bearing setting. They can be set to provide optimum performance in almost any application.

 At assembly, the conditions of bearing setting are defined as: End play An axial clearance between rollers and races producing a measurable axial shaft movement when a small axial force is applied - first in one direction, then in the other, while oscillating or rotating the shaft. Preload An axial interference between rollers and races such that there is no measurable axial shaft movement when a small axial force is applied - in both directions, while oscillating or rotating the shaft. Line-to-line A zero setting condition; the transitional point between end play and preload.

Note: The tapered roller bearings are usually applied with axial load. Under this condition, bearing will have an increased displacement. Please check the charts in next page for the relationship of displacement value and the load amount of tapered roll bearings.

● Deep groove ball bearing radial internal clearance and axial internal clearance

● Tapered roller bearing axial load and axial displacement