FORESEEING METHOD OF FAILURE OF BEARING

PURPOSE:To perceive the breakdown of a lubricating film of molybdenum disulfide of a bearing and thereby to enable prevention of a failure of an apparatus by lowering the temperature of the bearing by cooling down a bearing element periodically, and by detecting a rise in a bearing friction torque. CONSTITUTION:A rolling bearing 2 lubricated by a solid-state lubricator containing molybdenum disulfide bears rotation of a shaft 1 and is fitted to a housing 3. When a periodic cycle of low and high temperatures is given to the bearing 2 in vacuum, each of friction torques in the low and high temperatures progresses first in a prescribed manner. However, the torque in the low temperature increases to be twice as large as that in the high temperature thereafter, and lastly an extraordinary increase in the friction torque is seen. This increase is caused by breakdown of a solid lubricating film. The friction torque in the low temperature starts to increase when the lubricating film starts to be broken down partially, and a solid contact occurs and results in burning when the lubricating film is broken down completely. By cooling down a bearing element periodically and monitoring the increase in the friction torque, accordingly, the breakdown of the lubricating film of molybdenum disulfide is perceived and a failure of an apparatus can be prevented.