How to choose the roller length of the three row roller slewing bearing?

Slewing bearings are also called slewing rings, which play an important role in many mechanical equipment as transmission components. Among them, the three row roller slewing bearing is suitable for occasions with large axial load, radial load and large tilting moment. For example, in some large construction machinery and equipment, three row roller slewing bearings are usually selected.

There are many standard models for the three row roller slewing bearing designed by Unique Transmission. If the standard model cannot meet the load requirements, a non-standard design is required, that is, the load of the slewing bearing can be increased by increasing the rollers’ diameter. Increasing the roller diameter can increase the load of a single roller.

The extra-large diameter three row roller slewing bearing can increase the load by lengthening the roller length. After the roller is lengthened, as the contact length between the roller and the raceway increases, the load-bearing capacity of the roller naturally increases.

But everything has advantages and disadvantages. Extended rollers can be used on large diameter slewing bearings, but they are not suitable for small diameter slewing bearings. The raceway of the three row roller slewing bearing is linear plane raceway. On a small-diameter circular flat raceway, the linear velocities of the two ends of the long roller differs greatly. Even with the constraints of the segmented cage or the integral cage, the rolling of the long rollers in the raceway is not normal. In the case of sufficient lubrication, it is rotating and creeping. And if there is no restraint of the cage, the rollers will run horizontally and skew in the raceway, which will seriously affect the use.

In order to reduce the rolling of the rollers in the raceway, a long roller can be divided into two sections, and extra-long rollers can also be divided into three sections. Use integral or segmented cages to arrange the flat rollers in two or three rows side by side, so as to avoid excessive linear speed differences and avoid serious creeping of the rollers.

When we need to increase the load of the three row roller slewing bearing by increasing the roller diameter or increasing the length of the roller, we need to choose according to the actual situation. If you have any questions in this regard during the selection and design, you are welcome to consult Unique Transmission, our engineers will provide you with professional solutions, optimize the design plan, increase the stability of the slewing bearing and improve the slewing bearings’ service life.