Features and applications of slewing bearings superior to ordinary rolling bearings

Aug 03, 2023

Bearings are divided into rolling bearings and sliding bearings according to the presence or absence of rolling elements. Slewing ring bearings belong to rolling bearings, and its rolling elements include balls and rollers. According to the form, the slewing bearings can be divided into: single-row ball type, double-row ball type, three-row roller type, single-row cross-roller type, double-row ball type, and light series slewing bearings. The product model covers 150mm–4500mm of various standard and non-standard models.

Features of slewing bearings superior to ordinary rolling bearings in the following aspects:

1. Generally speaking, the slewing bearing has an ABS ring gear for rotation drive and a sealing device for anti-fouling. These devices play an important role in ensuring the normal operation of the slewing bearing at low speed and under long-term load.

2. The size of ordinary rolling bearings is generally relatively small, while the size of slewing bearings is relatively large, with a diameter of generally 0.4–10 meters, and some slewing bearings have a diameter up to about 40 meters.

3. In terms of operating speed, compared with ordinary rolling bearings, the operating speed of slewing bearings is lower, generally at 50 rpm. On many occasions where the bearing needs to be turned over, the slewing ring does not run continuously but only rotates back and forth within the angle of view, which is equivalent to "swaying the bearing".

4. The installation method of the slewing bearing is different from that of the ordinary rolling bearing. The slewing bearing is not set on the shaft and installed in the rolling bearing box like ordinary rolling bearings, but is only fixed on the upper and lower rubber supports with screws.

5. Slewing bearings usually have to bear loads in multiple directions, not only to bear radial force and axial force but also to bear a large collapse torque. Therefore, a complete set of slewing bearings usually acts like several sets of ordinary rolling bearings.

6. In terms of raw materials, quenching, tempering, and other manufacturing processes, slewing bearings are quite different from ordinary rolling bearings.

Slewing bearings are widely used. Construction machinery is the most widely used place for slewing bearings. The most common ones are earth-moving machinery, excavators, rotary conveyors, cranes, tower cranes, and other construction machinery.

Generally, the Single-row four-point bearings is commonly used. The heavy-duty series generally uses a three-row ball-slewing bearing with three seat rings. This is the one with the largest bearing capacity among the four products. It has relatively large axial and radial dimensions and a firm structure. It is especially suitable for heavy machinery, such as bucket wheel excavators, wheeled cranes, marine cranes, port cranes, molten steel running tables, and large-tonnage truck cranes.

FV Bearing has rich experience in the research and manufacture of slewing ring bearings. Some times ago, we just customized a slewing ring bearing with a diameter of 4800mm for a customer in Egypt. This bearing is used on a stacker crane. Customers are very satisfied with the stable performance of our bearings.