Test results for ball-bearings in the drives of systems and scientific equipment of a spacecraft in oscillatory operational mode

This paper aims at elucidating some special operational aspects of instrument ball bearings used in systems and scientific equipment of a spacecraft in oscillatory mode in vacuum with the lubricant VNII NP-274n. The service life of such bearings is mostly determined by the lubrication mode, as well as anti-torque moment, which is an indicator of internal energy losses. To observe these parameters in the course of bearings operation in oscillatory mode in vacuum an electromechanical test rig was set up. The test data obtained in oscillatory mode were compared with data obtained during continuous rotation of the same bearings. Based on the results of the tests, a lubricating mode was determined, an empirical formula was proposed for the relationship between the anti-torque moment and oscillatory motion parameters, as well as recommendations on extending the service life were provided. The paper may be of use to developers of systems and scientific instrumentation of a SC with oscillating shaft, which uses as supports ball bearings with predominantly axial load.