Turntable bearing, also known as slewing bearing, is a kind of large bearing which can bear large axial load, radial load and overturning moment at the same time. Turntable bearings are usually equipped with mounting holes, internal or external gears, lubricating oil holes and sealing devices, so that the main engine structure design is compact, the guide is reliable and the maintenance is convenient.
There are four point contact ball bearings with or without teeth, external teeth and internal teeth, double row angular contact ball bearings, cross cylindrical roller bearings, cross tapered roller bearings and three row cylindrical roller combined rotary bearings. Among them, four point contact ball bearing has higher static load capacity; cross cylindrical roller bearing has higher dynamic load capacity; cross tapered roller bearing can make bearing have greater support rigidity and higher rotation accuracy through pre interference.
Rotary bearing is widely used in hoisting machinery, mining machinery, construction machinery, port machinery, ship machinery, high-precision radar machinery and missile launcher and other large rotary devices.