Internal operating clearance of a spherical roller bearing — the space between the rollers and the outer ring, — can also be critical to the application. Internal operating clearance is also encoded in the nomenclature. For example, a suffix could be shown as C2, C0, or C3, with C0 representing normal tolerance; C2, less clearance than normal; and C3, more. Be sure to check nomenclature designations on a given bearing with a catalog from the maker of that bearing to assure meanings of all suffixes in the nomenclature. There are some variations among manufacturers.
As an example of the usefulness of operating clearance suffixes in bearing nomenclature, high-temperature or highspeed applications provide better service if additional clearance (C3) is provided. Lower clearance (C2) may increase service life in a heavily loaded, low-speed application, because more roller surface is in contact with raceways.