Structure and installation of slewing bearing

  Slewing bearing, is a large bearing capable of bearing comprehensive loads. 

  According to the external structure, there are three types of slewing bearings: gearless, external and internal. According to the internal structure, it can be divided into four series, and the characteristics are as follows: Four-point contact ball bearing: it has a high static load capacity and provides smooth rotation.

  Double-row angular contact ball bearings: easy to assemble, can withstand large axial force and overturning moment, suitable for medium and above loading and unloading machinery, such as tower cranes, truck cranes, etc.

  Cross-cylindrical (tapered) roller slewing bearing: It has high dynamic load capacity and can obtain greater support rigidity and slewing precision through preload.

  Three-row Cylindrical Roller Combined Bearing: It has extremely high carrying capacity, and the diameter of the bearing can be greatly reduced under the same force, making the structure of the main engine more compact.

Before installing the slewing bearing, check the matching surface. The parts supporting the slewing bearing should have sufficient rigidity, and the matching surface should be machined to meet the flatness and inclination required by the relevant standards. Each set of slewing bearings will be marked with a hardened soft belt "S", and the soft belt should be placed in the non-load area during installation. When installing, the bearing should be positioned radially first, then the mounting bolts should be tightened crosswise, and the rotation of the turntable bearing should be checked. In order to ensure the smooth rotation of the slewing bearing, the gear meshing inspection should be carried out before the installation bolts are not fully tightened, and the prestress of the tightened bolts should be 70% of the yield limit of the bolt material. The slewing bearing of BRS has been injected with grease before leaving the factory. Normally, after the bearing is installed and put into operation for 100 hours, it should be checked and replenished with grease once, and then repeated every 500 hours of continuous operation. When the slewing bearing in high temperature environment is working, the cycle of replenishing grease should be shortened appropriately. When the bearing is stored for a long time, or the machine stops running for a long time, the grease should also be replenished.