What does the suffix C3 for FAG bearings mean? "C3" is the suffix of FAG bearing desination, means: Internal clearance C3, which greater than normal internal clearance. This is common in applications with higher operational temperatures or when there is a need to accommodate thermal expansion. For more information, please refer to Schaeffler bearing suffix.
The radial internal clearance applies to bearings with an inner ring and is determined on the unmounted bearing. It is defined as the amount by which the inner ring can be moved in a radial direction from one extreme position to the other in relation to the outer ring.
The radial internal clearance groups are defined in DIN 620-4 and ISO 5753-1 and are described in DIN 620-4 by means of codes that comprise the capital letter C and a number. ISO 5753-1 designates the groups by the word "Group" and a number
| Internal clearance group | Description | Application | |
|---|---|---|---|
| DIN 620-4 | ISO 5753-1 | ||
| C2 | Group 2 | Internal clearance < CN | For heavy alternating loads combined with swivel motion |
| CN | Group N | Normal internal clearance, CN is not included in bearing designations | For normal operating conditions with shaft and housing tolerances |
| C3 | Group 3 | Internal clearance > CN | For bearing rings with press fits and large temperature differential between the inner and outer ring |
| C4 | Group 4 | Internal clearance > C3 | |
| C5 | Group 5 | Internal clearance > C4 | |