Internal clearance refers the total distance by which one ring can be moved radially or axially in relation to the other ring under a defined load. There are two types of internal clearance – operational clearance (after the bearing is mounted) and unmounted clearance (before the bearing is mounted). Operational clearance will always be greater than unmounted clearance. That’s because the interference fits of mating components cause bearing’s rings to expand or compress.
Spherical plain bearings from BL are produced with standard “normal” clearance so that a suitable amount of operational clearance can be achieved when bearings are installed as recommended and operated under normal conditions. Bearings with a greater or smaller internal clearance may be required for other conditions, such as when both rings are mounted with an interference fit or where unusual temperatures prevail.
Standard "normal" clearances vary by bearing series. Please contact us if actual clearance data is required.