Self Aligning Roller Bearings

Self aligning roller bearings are designed to provide a good radial load capacity at high speeds. They also provide an automatic centering function. This feature prevents detachment of the rollers and shaft deflection caused by Angle error. As a result, they are ideal for various applications. For example, they are often used in rolling neck bearings and general industrial machines.

When a wheel and tyre assembly wobbles about a self aligning roller bearing, it can create a lot of noise. However, the noise and vibration are largely reduced by the design of the self aligning bearing. The self aligning bearing also prevents the shaft from deflecting. In addition, it has a cage and a large outer ring. These features help to reduce friction and extend the service life of the bearing.

To achieve these advantages, the self aligning roller bearing has an outer ring, an inner ring, and two rows of rollers. The two rows of rollers are separated from each other by a cage. Cages are usually made of reinforced glass fiber or machined brass. Their low carbon content minimizes wear and friction.

Self aligning roller bearings are available in tapered and straight bores. Unlike deep groove ball bearings, they have a spherical shape on the outer ring. Because of this shape, there is little contact between the ball and groove. Nevertheless, this is not a perfect solution for misalignment problems. Therefore, a special heat treatment is required to guarantee a hardness that corresponds to the rolling bearings.

Axial loads are supported by rollers arranged between the inner ring and the outer ring. The two rows of rollers are staggered to compensate for the reduced ball contact area. Rollers on the inner ring are held in place by the cages, while those on the outer ring are secured by the pawl. If the pawl becomes loose, it can detach the spherical roller from the cage. Depending on the size of the bearing, the axial load capacity can vary from 10 kN to 400 kN.

The rollers are kept in position by the inner ring, which is stamped steel. It is also possible to have cages made of polyamide. These materials combine the strength and elasticity of steel with the low carbon content of polyamide. Besides preventing the rolling elements from sliding off, the cages also help to improve their stability and provide additional support.

For very high swivel angles, rod ends with integrated self-aligning bearings are ideal. They can be mounted in rotating machines with minimal maintenance. Additionally, they can be relubricated without tools.

Some common types of self aligning bearings include the NADELLA DURBAL WLT, which has a double row spherical roller. Other bearings, such as the SKF type, are popular for final drive pinion shafts, in-line injection pump camshafts, and crownwheel bearings. Moreover, the spherical roller bearing is suitable for applications in various environments. Depending on the application, the bearing can be either sealed or unsealed.

The most important aspect of a bearing is its angle of contact. For example, a duplex bearing is only considered if axial loads are dominant. Similarly, a single row self-aligning bearing has a lower radial load capacity than a deep groove bearing.