The self-aligning ball bearing was invented by It has two rows of balls and a common concave sphered raceway in the outer ring. The bearing is consequently self-aligning and insensitive to angular misalignments of the shaft relative to the housing. It is particularly suitable for applications where considerable shaft deflections or misalignment are to be expected. Additionally, the self-aligning ball bearing has the lowest friction of all rolling bearings, which enables it to run cooler even at high speeds.

produces self-aligning ball bearings to several designs. These are

– open bearings of the basic design

– sealed bearings

Basic design

The basic design self-aligning ball bearing is available with a cylindrical bore or, in certain size ranges, with a tapered bore (taper 1:12).

Large self-aligning ball bearings in the 130 and 139 series originally developed for specific applications in paper mills, can be used in any application where low friction is preferred over high load carrying capacity. These bearings are provided with an annular groove and lubrication holes in the outer ring and lubrication holes the inner ring .

The balls of some bearings in the 12 and 13 series protrude from the sides of the bearing . The overall width, T, of these bearings (over the balls) is provided in the product tables and should be considered when designing the associated components of the bearing arrangement.

Sealed bearings

self-aligning ball bearings are also available in a sealed version with contact seals at both sides - designation suffix 2RS1 . These sheet steel reinforced seals are made of oil and wear-resistant acrylonitrile-butadiene rubber (NBR). The permissible operating temperature range for these seals is –40 to +100 °C and up to +120 °C for brief periods. The seal lip contacts a smooth chamfer on the inner ring with light pressure.

Sealed bearings are lubricated as standard with a grease with a lithium thickener, that has good rust inhibiting properties and other characteristics according to the table. The grease life can be estimated according to the method explained for single row deep groove ball bearings (section "Sealed bearings - Grease life") using diagram 1 (grease MT33 or MT47). Calculations can be made with the program "Grease life for sealed bearings".

sealed self-aligning ball bearings are available with a cylindrical bore. Some sizes are also available with a tapered bore (taper 1:12).

Sealed bearings are lubricated for life and require no maintenance. They should not be heated above 80 °C before mounting and should not be washed.