摘要
润滑油在轴承内的分布及其变化规律对轴承的润滑性能有显著影响.在本文中搭建了滚动轴承模拟试验台,基于激光诱导荧光方法实现了滚动轴承内钢球-外圈接触区附近润滑油分布的观察与测量,获得了润滑油供给油层分布的三维形貌图,研究了不同供油量和转速对轴承内部供给油层分布的影响规律.试验结果表明充分润滑条件下相邻钢球-外圈接触区供给油池之间会形成相互连接的油带;在高速情况下,钢球-外圈接触区供给油层厚度受前一个接触区尾部空穴影响而减小;供油量的增加会增大表观油池,但并不意味着入口有效供油层的增加.
Rolling bearing is one of the most important rotary components in mechanical equipment.It has been commonly accepted that the lubricating performance is intrinsically linked to the stable and long-life operation of rolling bearings,while the distribution and variation of lubricating oil in bearings have a significant influence on the lubrication performance of rolling bearings.A ball-on-disc test rig has been widely used to study the lubrication performance and mechanism as it is easy to control the various operating conditions manually.In contrast,the lubrication in a rolling bearing is less understood.In practice,the lubrication inside a rolling bearing is quite different from that of a single ball-on-disc model because the rolling bearing contains multiple parts and works at more complex conditions.Therefore,it is difficult to directly apply single-point lubrication theories to rolling bearings.In this paper,a custom-made rolling bearing test rig was developed to simulate the multiple contacts of real rolling bearings and to study the lubrication performance.A commercial deep groove ball bearing was used as the test bearing.The steel outer ring of the test bearing was replaced by a glass ring to provide an optical window.The number of balls in the test bearing was 12.The test bearing was radially loaded.The inner ring was driven by a servo motor.The oil was tagged with a fluorescent dye,which emitted fluorescent light induced by laser,and therefore the laser induced fluorescence method can be used to observe and measure the distribution of lubricating oil near the ball-outer ring contact region in the rolling bearing.The film thickness of the oil was proportional to the fluorescent intensity under certain conditions.The relation between the film thickness of the oil and the fluorescent intensity received by the high speed camera was determined based on static film thickness calibration.As a result,three-dimensional distribution map of oil in the rolling bearing was obtained at speed range of 6 r/min to 1000 r/min.Based on the fluorescence technique,the oil distributed on the balls,the cage and in the pocket can all be found.This paper mainly discussed the influence of different oil supply volume and rotating speed on the distribution of oil reservoir near the contact formed by the outer ring and the rolling balls in the bearing.The results showed that the oil reservoir for each contact was independent oval oil pool at lower speeds while the oil reservoirs of adjacent contacts can be connected with each other through an oil string at higher speeds.The width of the oil reservoir as well as the oil string got wider with the increase of rotating speed of the inner ring under fully flooded lubrication conditions.A cavitation was found to split the outlet zone of oil reservoir.As the adjacent contact was linked with oil string,the cavitation gradually elongated with the increasing rotating speed and got close to the inlet zone of the next contact.The apparent oil reservoir increased with the increase of oil supply;however,the effective inlet oil supply layer may not increase.The thickness of the inlet oil supply layer increased firstly with rotating speed and started to decrease at high speeds.It was found that the extension of the cavitation from previous contact to next contact zone was the main cause of the reduction of the inlet layer thickness.The study of oil distribution presented in this paper can shed some light on certain aspects of the oil supply in oil-lubricated bearings,thereby contributing to the further development of the lubrication theory for rolling bearings.
作者
范志涵
赵自强
梁鹤
张宇
王文中
张生光
FAN Zhihan;ZHAO Ziqiang;LIANG He;ZHANG Yu;WANG Wenzhong;ZHANG Shengguang(School of Mechanical Engineering,Beijing Institute of Technology,Beijing 100081,China;Aero Engine Academy of China,Beijing 101304,China)
出处
《摩擦学学报》
EI
CAS
CSCD
北大核心
2022年第2期234-241,共8页
Tribology
基金
国家重点研发计划(2018YFB2000604)
国家自然科学基金项目(51805031,51675046)
摩擦学国家重点实验室开放基金(SKLTKF18A01)
国防技术基础科研项目(JSZL2019213B001)资助。
关键词
滚动轴承
激光诱导荧光
润滑油分布
油层厚度
空穴
rolling bearing
laser induced fluorescence
lubricant distribution
oil layer thickness
cavitation