The bearing group is split first by whether the bearing comes in a housing. Mounted bearings are supplied in a pillow block, flange, take-up or hanger housing that bolts to the machine, in ball, tapered roller and spherical roller forms. Unmounted bearings are the bearing alone, for a machined housing: cam followers, cylindrical, deep groove ball, spherical roller, needle, angular contact, self-aligning ball, tapered roller and thrust bearings. Insert bearings and cartridge units are the replaceable heart of a mounted unit. Rod ends and spherical plain bearings carry linkage motion, and bearing parts and kits cover adapters, end caps, shields and take-up frames.
Also known as: industrial bearings, ball and roller bearings, mounted bearings, bearing units, anti-friction bearings
Series in this category
Related guides: Bearing selection guide, Bearing lubrication basics, Bearing clearance codes, ER bearings explained, Pillow block bearing sizes, Cross-reference help
| Specification | What it means |
|---|---|
| Rolling element | Ball, cylindrical roller, tapered roller, spherical roller or needle roller, which sets load capacity, speed and how misalignment is handled. |
| Bore size | The shaft diameter, in inches or millimeters. Sealmaster and Browning mounted units encode inch bores in sixteenths in the part number. |
| Dynamic load rating | The basic rating used to calculate bearing life against the applied load, listed in pounds or kilonewtons. |
| Radial clearance | Internal clearance between rolling elements and raceways: C2 less than standard, standard, C3 and C4 progressively greater. |
| Seal type | Labyrinth, felt, rubber lip, spring-loaded or V-ring, which decides drag, temperature limit and how much contamination the bearing excludes. |
| Housing style | On mounted units: pillow block, flange block, cartridge block, take-up or hanger, which is how the bearing attaches to the machine. |
| Misalignment | The angle the bearing is rated to take up, and whether that is static only or dynamic. |
| Ability to relubricate | Whether the bearing has a grease fitting or lubrication holes, or is sealed and greased for life. |
A ball bearing makes a small elliptical contact with its raceway, which keeps friction and heat low and allows higher speed, but limits it to light and moderate loads. A roller bearing makes a line contact over a larger area and carries moderate to heavy loads and shock, at lower speed. Tapered and double-row spherical rollers also carry thrust in combination with radial load.
A mounted bearing is supplied inside a housing that bolts to the machine, such as a pillow block or flange unit, with the insert self-aligning in the housing to take up static misalignment. An unmounted bearing is the bearing alone and needs a machined housing and shaft seat to the manufacturer's fit recommendations.
C3 is an internal radial clearance greater than standard. Spherical roller bearings are made to industry-standard clearance ranges, with C2 below standard and C3 and C4 above it, and the choice depends on the fits and the temperature difference between shaft and housing in service. Other bearing types use clearances set by the manufacturer.
It depends on speed, contamination, temperature and lubricant. A non-contacting labyrinth seal is for dry, clean, faster running and cannot be blown out by over-greasing. A rubber lip contact seal handles wet and dirty conditions to 250 degrees F. A felt seal filters light to moderate contamination with less drag than a rubber lip and purges old grease on relubrication.
