The purpose of a ball bearing is to reduce rotational friction and support both radial and axial loads. It achieves this by using at least two races to contain the balls and transmit the loads through the balls. In most applications, one race is stationary and the other is attached to the rotating assembly (e.g., a shaft or hub). As one of the bearing races rotates it causes the balls to rotate as well. Because the balls are rolling they have a much lower co-efficient of friction than if two flat surfaces were sliding against each other.
There are several different types of ball bearing suitable for many different applications. The most common types of ball bearings are angular contact ball bearings, single row deep groove ball bearings and double row deep groove ball bearings.
Angular contact ball bearings have raceways in the inner and outer rings that are displaced with respect to each other in the direction of the bearing axis. This means that they are designed to accommodate simultaneously acting axial and radial loads. The axial load carrying capacity increases with increasing contact angle. Like deep groove ball bearings, the angular contact ball bearing is available as a single or double row type.
Single row deep groove ball bearings are probably the most common type of ball bearing in use, this is down to their versatility. They are simple in design, suitable for high speeds, non-separable and are very robust in operation, requiring very little maintenance. Deep raceway grooves and the close conformity between the grooves and the balls enable deep groove ball bearings to accommodate axial loads in both directions, even at high speeds.
The most popular sizes of deep groove ball bearings are available either rubber sealed known as 2RS or metal shielded known as ZZ. This offers protection from the ball bearing being contaminated with dirt, but usually at the cost of a slower limiting speed.
Double-row deep groove ball bearings correspond in design to the single row variety, with common inside and outside diameters. These ball bearings have twin grooves to accommodate two rows of balls. This means that they are wider than the single row bearings but have a much greater load carrying capacity, and are therefore a preferred alternative to where a single row bearing would not be strong enough.
All of our catalogues are available to download in PDF format. To view our catalogues see links to the main Bearings and Bushes catalogue and main Ball Bearing sections below.
Bearings, Plummer Blocks and Self Lube