The slewing bearing has the characteristics of compactness, convenient guiding and rotation, simple and convenient installation and simple protection, etc. It is widely used in lifting and transportation machinery, mining machinery, construction machinery, port machinery, wind power generation, medical equipment, radar and missiles On large-scale reversing equipment such as launchers, in addition to these, the slewing bearing can also withstand axial loads, radial loads and overturning moments that are larger than itself. A large bearing with special structure that integrates various functions.