抄録
The structure of a novel axle bearing endurance test equipment which we developed and the progress of an endurance test of axle bearings which are used on bogies of the series E5 are reported as the subject of this paper. The test equipment enables a test under a same high speed condition of over 320 km/h simultaneously for four bearings. In addition, it can provide an axial/radial load and vibration under actual conditions. One of the superior characteristics of the equipment is that it enables the evaluation test for four bearings at the same time without rail and wheels, that is, without wheel rolling. With the aim of ensuring the quality assurance/control and the future development of the bearings, a long-term endurance test of axle bearings is currently in progress by using this equipment. As test pieces, two of them are oil bath lubrication bearings which are same as the bearings equipped in series E5. The other two is grease-lubricated bearings as part of developing bearings. 4.1 million kilometers with oil bath lubrication and 2.9 million kilometers with grease-lubricated has been completed as of March 2015. The dimensions of both bearings have been shifting within the standard value and there were not any significant changes in their shapes. We always monitor the temperature and the vibration of all the test pieces but we could not detect abnormalities in the state quantities so far.
