微量第二介质辅助水润滑的临界转速的研究  

Critical Speed of Assisted Water Lubrication with Small Quantity Secondary Lubricant

作　　者：季浩 禹涛 张晓寒 郭峰 梁鹏[1] 陈召宝 JI Hao;YU Tao;ZHANG Xiaohan;GUO Feng;LIANG Peng;CHEN Zhaobao(School of Mechanical&Automotive Engineering,Qingdao University of Technology,Shandong Qingdao 266520,China;Key Lab of Industrial Fluid Energy Conservation and Pollution Control,Qingdao University of Technology,Shandong Qingdao 266520,China;Jinan Shunmao Test Instrument Co.Ltd,Shandong Jinan 250024,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 [2]青岛理工大学工业流体节能与污染控制教育部重点实验室,山东青岛266520 [3]济南舜茂试验仪器有限公司,山东济南250024

出　　处：《摩擦学学报》2023年第3期274-282,共9页Tribology

基　　金：山东省重点研发计划项目(2019GHY11205908);国家自然科学基金(52175173)资助.

摘　　要：由于水的低黏度,水润滑在临时突发的恶劣工况下易发生失效.本文中利用橡胶块-钢环线接触研究了微量乳化油介质临时辅助水润滑的概念.结果证明了乳化油临时辅助水润滑的有效性.橡胶块-钢环线接触水润滑存在一临界转速,当转速小于或大于此临界转速时,微量乳化油的短时注入使得摩擦力降低或增加.供油量和载荷均对临界转速有显著的影响,临界转速会随着供油量的减小而增加,随着载荷的增大而增大.基于Stribeck曲线对临界转速的供油量和载荷依赖性进行了分析.表面测量结果表明,无论转速高低,注入微量第二润滑介质均可降低磨损.Water-lubricated bearings have attracted more and more interests in industry because of its advantages of low cost and environmental friendliness.However due to its low viscosity and poor load-carrying capability,water usually cannot work as well as oils under unexpected temporary harsh working conditions,for example,low operation speeds at start up/shut down,short-time dynamic impact and heavy load.Consequently excessive friction,wear and noise can be found.At present,many studies had been carried out to improve the performance of water-lubricated bearings,and most of them were focused on materials and mechanical structures of bearing bushings.In this paper it was demonstrated that a small quantity of emulsifying oil could be employed as a secondary lubricant to assist water lubrication under mixed/boundary lubrication regime and a critical speed was identified and investigated,at which there was no friction coefficient change with a secondary lubricating medium.A block-on-ring test rig(Model MRH-3),which was capable of measuring the coefficient of friction online under fixed loads and speeds,was used.In the experiments,a rubber blockon-steel ring contact was enclosed within the chamber filled with water.With a deliberately fabricated needle nozzle emulsifying oil,as a secondary lubricating medium,could be ejected to inlet of the water lubricated contact under mixed lubrication medium with prescribed flow rate and injection time.The loads applied were 175,350 and 700 N,respectively.The flow rate of the emulsifying oil ejection was fixed at 10μl/s.The total oil supply quantities were 25,50,75 and 100μl.The emulsifying oil was supplied when the pre-running of the water-lubricated contact was finished and the friction force was stable.The results validated the feasibility of the injection of the small amount of emulsifying oil to enhance the water lubrication.Moreover it was found that there existed a critical ring rotational speed,at which the measured coefficient of friction did not change when the emulsifying

关 键 词：水润滑 第二润滑介质 临界转速 供油量 载荷 

分 类 号：TH117.2[机械工程—机械设计及理论]