轮毂轴承润滑脂失效的流变学分析.pdf

2013年8月
润滑与密封
Aug.2013
第38卷第8期
LUBRICATION ENGINEERING
Vol. 38 No8
DOI:10.3969/j1isn.0254-0150.2013.08.016
轮毂轴承润滑脂失效的流变学分析
吴宝杰米红英2刘庆廉郭小川陈徳友2张广辽
(1.中国石化股份公司润滑油天津分公司天津300480;2.中国人民解放军总后勤部油料研究所北京102300;
3.中国人民解放军后勤工程学院重庆401311)
摘要:用 Physica MCR3?I旋转流变仪对5种轮毂润滑脂流变特性进行测试,并结合行车试验结果进行讨论,分析.
基础油黏度和类型、增黏剂、稠化剂类现和浓度等参数在不同温度条件下对润滑脂流变性能的影响,并对产生的机制进3
行探讨。结果表明:120℃下弹性模量超过80kPa、应变幅度接近4%、表观黏度大于20Pa-s的润滑脂在轮毂轴承中表S
现出了优异的高温使用性能。轮毂温度升高引起轴承内润滑脂的流变学参数发生显著变化是润滑脂失效的主要原因,通
过提高稠化剂含量、选用复合稠化剂来增加高温下的弹性模量,提高基础油黏度来增大高温下应变幅度,加入特种高分
子增黏剂来提高表观黏度,可以提高轮毂轴承润滑脂在高温下的性能。
关键词:润滑脂;轮毂轴承;流变;弹性模量
中图分类号:TH117.2文献标识码:A文章编号:0254-0150(2013)8-076-7
Analysis on Failure of Hub Bearing Greases Based on Rheology
Wu Baojie Mi Hongying Liu Qing ian Guo Xiaochuan Chen Deyou Zhang Guangliao
(1. Tianjin Branch of SINOPEC Lubricant Company, Tianjin 300480, China
2. Petrol-oil and Lubricants Research Institute of General Logistics Department, PLA, Beijing 102300, China;
3. Logistic Engineering University of PLA, Chongqing401311, China)
Abstract: Rheology properties of five hub greases were measured by Physica MCR301 rheometer, and the results were
discussed combined with these grease fieldwork data. The influences of the parameters such as base oil viscosity and type
tackifier, the type and concentration of thicker on the rheological properties under different temperatures were studied, and
the mechanism was discussed. The results show that the greases, with elastic modulus value of exceeding 80 kpa, strain am
plitude of approximate 4%, apparent viscosity of more than 20 Pas at 120 C, have the perfect high temperature perform-
ance in hub bearing. The primary cause of hub bearing grease failure is the marked change of grease rheology parameters
due to the temperature rising of hub bearing By adding the content of grease thickener and choosing lithium complex to en-
hance the elastic module, increasing base oil viscosity to enlarge grease strain amplitude, adding special polymer in grease
formula to boost grease apparent viscosity, the high temperature performance of the hub bearing greases can be improved
Keywords: lubricating grease hub bearing; rheology; elastic modulus
流变学是研究物质流动和变形的一科学,多数度的关键指标]。在中低剪切速率下润滑脂流变性能
物质对外力表现为弹性和黏性双重特性,具有这种特的数学模型一般符合 Herschel- Bulkley方程r=T。+
性的物质称之为黏弹性物质,润滑脂是其中一种,其m(du/dz)"?,这里的表观黏度η受基础油黏度和稠
流变性能会因配方组成的不同具有较大差异“。流化剂特性浓度2个因素影响叩。润滑脂在轴承中以动
变测试包括稳态流变实验、瞬态流变实验和动态流变空间润滑脂和静空间润滑脂2种形式存在,分别起到
实验,动态流变实验对样品微观结构损伤最小,其中密封和润滑的作用?,两类润滑脂在结合处会出现
弹性模量和黏性模量“可以反映出润滑脂结构的个从0到一定值剪切速度的过渡区域,温度和剪速控
变化情况,应变幅度γ是衡量润滑脂开始涴动难易程制着静空间润滑脂的流失,即屈服应力。和表观黏
度η是关键参数。 J L#uger等?发现润滑脂随着温度
收稿日期:2013-01-28
的降低P和C"都要增加,应变幅度γ也随之增加
作者简介:吴宝杰(1972ー),男,硬士,高级工程师,从 L Thomas等·认为润滑脂基础油的极性越大弹性模
事润滑脂配方开发和应用研究,E-mal: wubj lube@ sinope。量C"越高,该规律是建立在范德华力的基础之上。
P M Cann等发现范德华力和毛细管力把基础油東