Structure and characteristics of slewing bearings

The slewing bearing is a large and super large bearing that can accept comprehensive loads and has a special structure. It has the characteristics of compact structure, flexible rotation, and convenient assembly and maintenance. Compared with other ordinary bearings, slewing bearings have the following obvious characteristics:

1. Large size

The diameter is usually 0.4m to 10m, and the maximum diameter can reach 40m.

2. High load capacity

Ordinary can accept axial load, radial load and overturning moment load together.

3. Low speed

The running speed is lower than 10r/min, and in a few cases, it does not rotate in a circle, and only rotates within a certain angle to make a swing movement.

4. Bearing with mounting holes

It can be fastened on the upper and lower supports seat with bolts.

5. No pivot

The inner ring or outer ring has a gear for rotating drive.

6. Bearing with smooth oil hole, can be installed in a sealed manner

The important construction methods of slewing bearings are: four-point contact ball slewing bearing, double row angular contact thrust ball slewing bearing, crossed cylindrical roller slewing bearing, crossed tapered roller slewing bearing, and three-row cylindrical roller matching slewing bearing.

According to the bearings with teeth or without teeth and the distribution of teeth, they can be divided into different structures, such as non-tooth type, external tooth type or internal tooth type.

Among them, the four-point contact ball slewing bearing has a higher static load capacity, the crossed cylindrical roller slewing bearing has a higher dynamic load capacity, and the crossed tapered roller slewing bearing can apply preload to improve the support rigidity and rotation accuracy. Cylindrical rollers are assembled with slewing bearings to increase the bearing height to improve the carrying capacity. The load can be carried by different raceways. Therefore, under the same stress condition, the bearing diameter can be greatly reduced, thus making the host more compact. It is a slewing bearing with high load capacity.

Slewing bearings are commonly used in large slewing support structures such as lifting and transporting machinery, mining machinery, construction machinery, port machinery, ships, and high-precision radars.