定量供油下球-环/球-盘接触形式润滑特性对比  

Comparison on Lubrication Characteristics of Ball-on-Ring/Ball-on-Disk Contact Configuration

作　　者：李桂枝 白清华 栗心明 杨萍 郭峰 金旭阳 LI Guizhi;BAI Qinghua;LI Xinming;YANG Ping;GUO Feng;JIN Xuyang(School of Mechanical&Automotive Engineering,Qingdao University of Technology,Shandong Qingdao 266520,China)

机构地区：[1]青岛理工大学机械与汽车工程学院,山东青岛266520

出　　处：《摩擦学学报》2022年第4期700-708,共9页Tribology

基　　金：国家重点研发计划(2018YFB2000600);国家自然科学基金面上项目(51875299)资助。

摘　　要：采用球-环接触和球-盘接触形式的光干涉润滑油膜测量仪,在定量供油条件下观察两种接触形式下的不同润滑特性,分析了润滑差异性的内在机制.结果显示:在低速条件下球-盘接触膜厚始终高于球-环接触膜厚,由接触几何特性差异导致的不同动压效应、侧泄效应和润滑剂流动是其主要原因;在高速条件下球-盘接触形式易出现入口乏油,而球-环接触在整个测试速度范围内未出现乏油,不同的离心力作用方向是导致这种差异的诱因.试验还观察与分析了黏度对两种接触方式下润滑特性的影响:低速条件下,高黏度润滑剂易导致球-环接触出现乏油;高速条件下,高黏度润滑剂能够推迟球-盘接触时乏油状态的出现.The main purposes of oil/grease lubrication in rolling element bearings are to reduce friction and to resist wear.To basically understand the lubrication mechanisms of rolling bearings,the contacts between rolling elements and outer or inner ring were reduced to a ball-on-disc(BOD)configuration,which is widely used as a simulation device.With this classical configuration,the lubrication features of concentrated contacts were described by measuring film thickness and friction coefficient.However,in absence of real contact geometry,the lubrication behaviors of practical rolling bearings cannot be properly reflected.For instance,the micro gaps surrounding the contact zone between BOD configuration and real contacts were different,resulting in a different capillary force.Thus,the local lubricant replenishment and oil reservoirs were different,which consequently affected the lubrication regime.This became more pronounced under a restricted oil supply.In addition,the direction of centrifugal force at the high speed of real bearing was also different from the situations of BOD configuration.That meant in BOD cases,the lubricant was thrown away from the flat disc surface,whilst the lubricant adhered to the outer ring surface of a real bearing.Unfortunately,studies associated with these effects were rarely conducted.Therefore,it was necessary to develop a ball-on-ring(BOR)configuration to further simulate the contacts of rolling elements and the outer ring of the real bearing,by which both effects of contact geometry and centrifugal force can be introduced.The main purpose of this study was to compare the lubrication behaviors between two configurations of BOD and BOR.To implement it,optical interferometry was employed to measure film thickness and to reconstruct the film profile under single lubricant charge conditions.The lubrication behaviors determined by the contact geometrical parameters were analyzed.The results showed that at low speeds the lubrication behaviors between BOD and BOR contacts were quite different.It

关 键 词：球-环接触 球-盘接触 乏油 定量润滑 离心力 

分 类 号：TH117.2[机械工程—机械设计及理论]