The diameter of shield machine slewing bearing varies from 2.5 meters to 6 meters, and some diameter is larger. This kind of bearing works in very harsh conditions, with large bearing load, strong corrosion resistance and short life.
Shield tunneling machine is the main construction machinery in shield tunneling method, which must have high reliability and can work stably and reliably. The main bearing of large shield machine mainly adopts three-row roller slewing bearing, which needs to bear large axial force and overturning moment in the working process, as well as certain radial force. The loading situation is complicated, and it is easy to produce large deformation, which affects the construction safety of shield machinery.