Swing Bearing : A combination of rings with balls or rollers capable of sustaining radial, axial, and moment loads of the revolving upperstructure with boom and load. (Spec 2C)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}