What effect does the clearance of the slewing bearing have on the use？



Clearance is an important technical parameter of slewing bearing, which directly affects the technical performance of the bearing's load distribution, vibration, noise, friction, temperature rise, service life and mechanical operation accuracy.


Too large clearance will cause the bearing internal capacity area to decrease, the stress on the contact surface will increase, the rotation accuracy will decrease, the vibration and noise will increase. As a result, the service life is shortened and the clearance is too small, the negative clearance (interference) may occur in actual operation, rotation jamming will be inflexible, resulting in increased friction and heating, increased temperature rise, which will make the effective clearance smaller or larger, this vicious circle will cause the bearing to lock and cannot rotate.


The bearing's clearance value is artificially specified by the designer and a certain range is divided according to the size of the slewing bearing, which is used as a reference value in the processing process. Therefore, if it is not specifically required by the operating conditions, the bearing clearance can allow an error of up to 0.05 within the specified range, which is not enough to affect the quality of the slewing bearing itself. While larger errors are not acceptable, which will cause the overturning and shaking of the slewing ring to become larger, which will affect the use.


The clearance of the slewing bearing can make up the installation error. If the clearance is too small, but the installation plane is rough and uneven, the installation screw will warp after being compressed, the force will be uneven during use, the rotation will not be smooth. In this case, first ensure the normal rotation of the bearing, a larger clearance is needed to offset the installation error. In the design stage, it is necessary to consider the flatness that can be achieved after the installation of the foundation and select the appropriate clearance.


Of course, the clearance value cannot be sloppy when the design rotation accuracy is high. Generally, zero clearance or negative clearance is selected to at least ensure that the bearing cannot have clearance. When repeated positioning accuracy is required, the clearance is very important for the slewing bearing. Even if there is no special requirement for the starting torque, the clearance value needs to be ensured within -0.02 to 0.


The clearance has a great influence on the slewing bearing. When designing, it is necessary to fully communicate with the user, understand the working conditions in detail and choose the clearance value reasonably to ensure that the slewing bearing is more stable and more durable.


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