Angular Contact Bearings Information
Image Credit: Emerson Bearing | ABT Bearing | SKF North America
Angular contact bearings are designed such that a contact angle between the races and the balls is formed when the bearing is in use. The major design characteristic of this type of bearing is that one, or both of the ring races have one shoulder relieved, or higher than the other. In order for these bearings to function properly, they must be assembled with a thrust load.
This loading (or preload) creates a line of contact (or contact angle) between the inner race, the ball and the outer race. The preload can be built into the bearing or created when the bearing is inserted into an assembly. The contact angle varies from 15° to 40° and is measured relative to a line running perpendicular to the bearing axis. Angular contact bearings are unidirectional thrust bearings that can withstand heavy thrust loads and moderate radial loads.
Please read How to Select Ball Bearings for more information.
Important dimensions to consider when searching for angular contact bearings include design units, bore, outside diameters, and outer ring width.
Design units can be in either inches or metric units. Some manufacturers may specify parts in both. The bearing industry uses a standard number system for bearings with metric diameter bores. For bore sizes 04 and up multiply by 5 to obtain the bore in millimeters. If the bore is a hex enter the dimension across the flats. If the bore is tapered enter the smaller diameter. The outside diameter of the bearing includes the housing if a housed unit, but excludes the flange if a flanged bearing.
Important operating specifications to consider when searching for angular contact bearings include rated speed, static radial load, and dynamic radial load.
The rated speed for a bearing running with grease lubrication is lower than a bearing with oil lubrication.
The static radial load is the maximum radial load bearing can endure without excessive permanent deformation.
The dynamic radial load is the calculated constant radial load, which a group of identical bearings with stationary outer rings can theoretically endure for a rating life of 1 million revolutions of the inner ring.
They can be relubricatable, prelubricated, and solid lubrication.
Bearing design for angular contact bearings can be one directional thrust, double direction thrust, double row, double row maximum capacity angular, duplex thrust, and four-pointed contact.
Manufacturers typically assign an ABEC rating to bearings. ABEC (Annular Bearing Engineers' Committee) ratings classify different accuracy and tolerance ranges for bearings. The higher the ABEC number the tighter the bearing tolerances. Please consult tables in the search form for Angular Contact Bearings for tolerances and other rating equivalents.
Styles of Seals & Materials
Angular contact bearings can have a number of different styles of seals or shielding. Seals and shields provide protection from contamination and as a retainer for lubricant. Seals provide better protection and lubricant containment than shields, but have lower maximum speed capabilities. Types include:
Angular contact bearings may be constructed of special materials including stainless steel, plastic, and ceramic hybrid. They may also be plated; common plating materials are cadmium and chrome.
Thin-section bearings have small cross-sections with respect to their diameter. Bearings with ball screw support are specially designed for use in ball screw or lead screw applications.
ABMA STD 12240-2 - This part of IS0 12240 specifies dimensions and tolerances for angular contact radial spherical plain bearings. The specified tolerance values apply to finished, angular contact radial spherical plain bearings before any coating or plating. Angular contact radial spherical plain bearings need not conform to the design illustrated but compliance is required as regards dimensions and tolerances specified.
BS ISO 12044 - Rolling Bearings - Single-Row Angular Contact Ball Bearings - Chamfer Dimensions For Outer Ring Non-Thrust Side
DIN 628-1- This standard specifies dimensions and symbols for single row self-locking angular contact radial ball bearings without filling slot, with cage and with a contact angle Î± of 40Â° (suffix B). It covers a selection of angular contact ball bearings of this design matched to the practical needs of users, taking into account the dimension plan specified in DIN 616.