Thermo-mechanical analysis of angular contact ball bearing

The thermal-mechanical character, which is difficult to ensure because of the lack of a corresponding theory and tool, has a significant effect on the dynamics of bearings. It even leads to a sudden failure of bearings in a working situation. In this research, a thermal deformation model was established, based on the analysis of temperature effect on the basic size of angular contact ball bearing. And the transmission from rolling size to bearing axial stiffness was explicit. On the basis of the variation of Hertz contact stiffness and the change of initial contact angle of angular contact ball bearing caused by temperature rise, a “Thermo- mechanical” model of bearing was proposed. According to this model, using the corresponding calculation procedure programmed by MATLAB, the effect of bearing temperature on the axial stiffness has been studied. And the correctness of this model was verified with experiments. Some design suggestions have been made for the decision of bearing preload: to prevent the bearing failure caused by overheating.     

Precessional slip in an angular contact ball bearing

A previously reported ball precessional motion in an angular contact bearing is analyzed. Explicit forms for ball-race slip are given, both with and without precession. Slip and entrainment velocity at ball-ball contacts in a retainerless bearing are also given, also with and without precession. It is shown that the observed precession does not change the hertzian slip fields very much at either contact, compared with those produced by pure spin.     

角接触球轴承刚度研究

针对角接触球轴承的接触角、轴向力以及轴承刚度之间的关系问题,通过对轴承建立静力平衡方程,对具有不同接触角(其它参数相同)的轴承进行刚度研究。研究表明:在相同轴向力作用下,轴承自由接触角越大,其轴向刚度越大,但轴向位移、径向刚度以及刚度比值(径向刚度/轴向刚度)都越来越小;在相同接触角情况下,轴向力越大,其轴向位移、轴向刚度和径向刚度都越来越大,但其刚度比值会越来越小。     

双列角接触球轴承保持架的改进

介绍了轧机用双列角接触球轴承保持架损坏形式及原因。对原保持架结构进行了改进,并介绍了新结构保持架的设计方法。     

双联组配角接触球轴承加工工艺的改进

针对组配角接触球轴承成品组配合格率低,大部分需要通过返工来保证成品凸出量等问题,对加工工艺进行了改进,使成品凸出量得到了较好控制,提高了成品组配合格率,缩短了加工周期,提高了生产效率,也为企业赢得了经济效益。     

密封角接触球轴承系列产品设计

针对传统的角接触球轴承无法安装密封圈的问题,从设计上对轴承结构进行了改进,解决了存在的问题,使密封圈有效隔绝轴承内部与外界各类物质的接触,提升轴承的使用寿命;并最大限度地实现了同种外形尺寸的15°和25°接触角轴承的外圈、保持架、密封圈的通用。     

关于角接触球轴承锁球高度的探讨

角接触球轴承锁球高度在实际生产中往往偏大,造成装球困难、经常出现卡伤钢球、破坏锁点甚至磕伤沟道的现象,致使轴承噪音增大,使用寿命下降。在理论分析及实际生产经验的基础上,可以根据接触角的大小及尺寸大小调整锁球高度或结构。     

关于角接触球轴承配对的一些分析

为更好地控制角接触球轴承配对使用中的预载荷及变形量,对各种配置形式给出了经验公式并进行了定量分析。     

角接触球轴承工作游隙的计算

主要阐述了游隙的概念并分析了影响轴承径向工作游隙的主要因素,以角接触球轴承为例分别计算轴承配合的有效过盈量、温度、离心力对工作游隙的影响,并通过轴承实例利用VB程序实现各影响因素变化量的计算。     

Skidding analysis of angular contact ball bearing subjected to radial load and angular misalignment

Journal of Mechanical Science and Technology - Skidding is a phenomenon that frequently occurs in ball–raceway contact areas of bearings and often leads to their early failure. This paper...     

双列角接触球轴承的游隙与接触角

通过对双列角接触球轴承轴向游隙、径向游隙、接触角关系的推导换算,分析影响接触角的各因素,采取合理可行的方法保证接触角。     

万能配对角接触球轴承组配过程分析

万能配对角接触球轴承主要用于精密机床上,不需要复杂调整,即可获得所需的预载荷,同时对其组配过程做必要说明分析。     

角接触球轴承筛选组配程序设计与开发

针对人工方式对角接触球轴承筛选配对与管理效率低的问题,开发了一套角接触球轴承筛选组配软件.该软件以 Visual Foxpro数据库为开发工具,通过建立轴承各项参数数据库,根据组配轴承型号、轴承配对方式和组配精度要求,从数据库中筛选符合要求的轴承进行配对计算,以报表的形式将配对单输出.程序还对未组配成功轴承按参数进行统计分析,供车间修订轴承加工条件.结果表明,该软件增强了轴承数据的统计分析效率,提高了轴承的组配率,满足了大批量,精细化的生产要求.     

基于COBRA的角接触球轴承仿真分析

借助COBRA软件对某角接触球轴承的游隙和结构参数进行了仿真分析,大大减少轴承的接触应力和滚道磨损发热量,缩短了设计周期,提高了生产效率。     

角接触球轴承沟道磨削加工表面谐波分析

在角接触球轴承沟道磨削加工过程中,为了对其表面谐波源问题进行辨识,提出了一种基于小波分解和重构与功率谱密度法(PSD)、相关性分析的频谱分析方法.首先,采用表面轮廓仪采集了磨削试验中的7006C球轴承内沟的实际截面轮廓信息,再用小波分解的"db5"小波基对其进行了5层分解,并根据圆度误差、波纹度和表面粗糙度的分界指标,...     

角接触球轴承组配时加载装置的改进

角接触球轴承组配时需要增加一定的轴向负荷来测量凸出量与凹进量。针对原来单一负荷装置测量范围小的问题,采用组合式负荷装置,在杠杆长度比值不变的情况下,增大了测量范围。     

双向角接触推力球轴承套圈沟道磨削与测量

针对双向角接触推力球轴承套圈结构特点,采用间接比较测量,解决无沟底内、外套圈磨削加工与检测,保证了产品的精度,达到了良好的效果。     

角接触球轴承动特性的数值与试验研究

角接触球轴承的动特性对机床主轴的回转精度、可靠性及寿命等有重要影响。以弹性力学理论、滚动轴承动力学和沟道控制理论为基础,研究角接触球轴承的动特性。推导了计及过盈配合量和预紧力影响的高速角接触球轴承动刚度计算方法,并对轴承动刚度的影响因素进行了理论分析和试验验证。结果表明:随着过盈量的增大,轴向刚度逐渐减小,径向刚度则逐渐增大,外圈过盈量影响更显著;预紧力过小时,刚度会出现明显的波动现象,适当的预紧力对角接触球轴承刚度的稳定至关重要。     

Laser-induced fluorescence for film thickness mapping in pure sliding lubricated, compliant, contacts

A laser-induced fluorescence (LIF) technique has been used to measure fluid film thickness in a compliant, sliding contact under low-load/low-pressure conditions. The soft contact between an elastomer hemisphere and a glass disc is lubricated by a liquid containing fluorescent dye. The contact is then illuminated with 532 nm laser light through the glass disc, and viewed with a fluorescence microscope. From the intensity of emitted radiation, film thickness maps of the contact are determined. Previous calibration procedures have used a separate calibration piece and test specimen with possible errors due to differences in reflectivity between the calibration and test specimens. In the work reported in this paper a new calibration process is employed using the actual test sample, thereby avoiding such errors.Results are reported for a sliding contact between PDMS and glass, lubricated with glycerol and water solutions under fully flooded and starved conditions. It was found that, for glycerol, the measured film thickness is somewhat lower than numerical predictions for both lubrication conditions. It is suggested that a combination of thermal effects and the hygroscopic nature of glycerol may cause the lubricant viscosity to drop resulting in thinner films than those predicted for fully flooded contacts. Starvation occurs above a critical entrainment speed and results in considerably thinner films than predicted by fully flooded I-EHL theory. A numerical study has been carried out to determine the effect of the observed starvation on film thickness. Predicted, starved film thickness values agree well with those obtained experimentally.     

三、四点角接触球轴承游隙计算的分析

通过对三点和四点角接触球轴承进行测量、计算、分析,探索游隙与接触角的几何关系,对其计算方法进行了改进。