滚滑轴承温度场的有限元分析

以滚滑轴承滑块为研究对象,建立了轴承滑块与内、外圈及滚动体的传热模型,用ABAQUS有限元软件的结构热-应力耦合作用进行了轴承滑块与内、外圈滚道接触面的温度场分析,得出了滚滑轴承在不同转速和不同径向载荷工况下滑块的温度分布特征。结果表明,轴承滑块与内、外套圈滚道的接触面温度随着转速及载荷的增大而升高,滑块与内、外套圈滚道接触面的各点温度相差很大;初步试验验证了滚滑轴承滑块的有限元温度分析的可行性。     

航空关节轴承挤压翻边固定的仿真和试验研究

对航空关节轴承挤压翻边安装固定进行了仿真和试验研究,通过ANSYS对轴承挤压翻边和轴向推出力进行了仿真,分析了轴承挤压翻边后相关参数的变化及其影响,对仿真分析结果进行了验证,试验结果与仿真分析的结果基本一致.结果表明,轴承与轴承座间隙配合时,轴承挤压翻边安装会降低轴承的空载启动力矩,现有安装工艺能够满足航空轴承安装固定...     

深沟球轴承动态接触特性有限元仿真分析

利用LS-DYNA建立了适用于行星减速机构中支撑行星轮的深沟球轴承的多体动态接触有限元模型,基于显式动力学有限元法,综合考虑了轴承外圈运转速度,径向载荷和行星架运转速度的影响,对轴承滚动体在不同工作条件下的动态接触特性(位移、速度、应力及接触力)等进行了仿真分析,得出了轴承的动态接触响应。研究表明,轴承中滚动体在运转过程中存在着公转与自转运动,与外圈和内圈接触时出现最大线速度和最小线速度。最大应力发生在与内外圈接触时,且最大应力受转速影响小,将赫兹解与仿真解进行比较,说明了分析的可行性。滚动体与保持架的接触力波动最大,数值最小;与内外圈接触力波动小,数值与径向载荷基本相同。     

陀螺框架轴承摩擦力矩分析

针对陀螺框架轴承要求启动摩擦力矩小而稳定的苛刻要求,建立轴承摩擦力矩分析模型,在已有的球与内外圈弹性滞后、差动、自旋、润滑影响因素引起的摩擦力矩分析基础上,重点考虑浪形及冠型保持架引起的摩擦力矩。求得的轴承启动、动态摩擦力矩与YZC-II测试仪测试结果吻合较好。分析表明,浪形保持架整体优于冠型保持架,保持架与球作用引起的摩擦力矩比例随轴向载荷减小而增大,该比重在启动过程中较大,在动态过程明显降低;通过对4种型号框架轴承不同转速的摩擦力矩分析,当转速低于2 r/min时,轴承摩擦力矩受转速影响不大,随着速度增大,启动速度对轴承启动摩擦力矩值、动态摩擦力矩波动范围影响突显出来。     

基于ADAMS的滚滑轴承摩擦力矩研究

针对在高速、重载的情况下轴承摩擦力矩较大,极容易发热和磨损,导致使用寿命大大降低的问题,基于轴承摩擦力矩测量原理建立了滚滑轴承的摩擦力矩数学模型,并以此为基础利用ADAMS软件建立了滚滑轴承的动力学仿真模型。考虑到摩擦力矩数值的波动性,对变化规律进行了分析,并给出了滚滑轴承启动摩擦力矩和动摩擦力矩在仿真试验中的提取方法;研究了不同径向载荷、转速、滚子与滑块之间的间隙和径向游隙对摩擦力矩的影响;借助SKF轴承摩擦力矩计算器,验证了仿真模型的正确性。研究结果表明:4种不同工况结构参数对滚滑轴承启动摩擦力矩和动摩擦力矩都有一定影响,该结果可为滚滑轴承降低摩擦力矩设计提供参考依据。     

基于有限元的谐波齿轮传动柔性轴承动态和接触特性分析

针对柔性轴承对谐波传动的承载能力、传动精度及寿命影响较大等问题,以谐波传动柔性轴承为研究对象,综合考虑轴承转速、载荷、变形等因素影响,基于ANSYS/LS-DYNA非线性接触分析方法对柔性轴承的动态和接触特性进行有限元仿真分析。研究结果表明,柔性轴承外圈不同位置动态特性基本相同,距离长轴不同距离的滚动体位移基本相同,速度以波峰波谷交替变化,且随距离增大而减小;外圈、滚动体应力主要集中在长轴附近,应力以波峰波谷交替变化,远离长轴后应力值减小;滚动体与内外圈接触力波动较大,且与外部载荷基本相同,与保持架接触力波动较小。     

高速数控机床主轴用角接触球轴承接触特性研究

通过综合考虑轴承受力、润滑、转速和温升的作用,建立了高速轴承力学模型,并将其与经验公式的计算结果进行对比。结果表明,随着位置角和径向载荷的变化,陀螺力矩发生规律性变化,在180°位置角时钢球所受的接触力最大,陀螺力矩最小;不同位置角下钢球与内、外圈的摩擦因数在0.04~0.12之间变化,随着轴承载荷的增加,摩擦因数逐渐变大;随着转速的增大,考虑离心膨胀作用时的内、外圈接触角比不考虑时要小,而内、外圈接触载荷比不考虑时要大。     

滚轮轴承的类型与结构

滚轮轴承是指其外圈不装入机座孔、轴承箱或轴承座内,而是直接在钢制轨道上滚动的轴承。其基本类型有螺栓型滚轮轴承、平挡圈型滚轮轴承、重型输送链条用滚轮轴承和行走机械用滚轮轴承。重点介绍了以上类型滚轮轴承的结构特点和使用情况。     

考虑弹流润滑效应的三点接触球轴承刚度特性分析

为获得润滑状态下三点接触球轴承更为准确的刚度特性,应考虑弹流润滑效应对轴承刚度的影响。文中基于拟静力学模型考虑高速离心力和陀螺力矩效应,根据给定轴承的结构参数和工况,计算滚动体与内外圈的法向接触载荷和各部件的运动速度。将拟静力学模型的计算结果和润滑介质参数代入弹流润滑模型,求解出滚动体与内外圈之间的压力分布和油膜厚度分布。进一步研究了转速、轴向载荷和润滑油的初始黏度对油膜压力和最小油膜厚度的影响。基于弹流润滑理论分析了转速和轴向载荷对轴承接触刚度、油膜刚度及综合刚度的影响。结果表明：转速的提高会大幅增加润滑油膜的整体厚度;润滑油初始黏度的增大会增加油膜厚度;随着轴承转速的提高,轴承的整体轴向刚度和轴向油膜刚度减小;随着轴向载荷的增大,轴承轴向刚度和轴向油膜刚度增大,且差值变化不大。     

深沟球轴承内部载荷序列与寿命计算

以深沟球轴承为研究对象,建立钢球与内外滚道的滚动接触模型,在疲劳寿命的计算中考虑轴承的运动特性。考虑球轴承中同时承载的滚动体个数随时间变化,提出了一种更为准确的载荷分布计算模型。分析了相同外部载荷作用下,不同游隙、不同转速对轴承内部载荷的影响。针对4种不同运动状态下的深沟球轴承,分析内圈、外圈和滚动体上一点的接触应力随时间的变化规律,计算得到其载荷序列。考虑内外圈不同运动状态对轴承应力循环次数的影响,对Lundberg-Palmgren(L-P)寿命模型进行了修正,计算了轴承内圈、外圈、滚动体以及轴承整体的寿命。对比不同运动状态下两种模型计算的寿命,在仅有一个套圈旋转时,修正的寿命与初始L-P寿命较为一致,当两个套圈同时旋转时,修正的L-P寿命与常用的L-P寿命计算结果存在较大差异。     

A Fatigue Life Comparison of Two-Row Tapered Roller Bearings and Spherical Roller Bearings

Tests were run to compare the fatigue life of two-row tapered roller bearings to that of spherical roller bearings. Both bearing types had an outer diameter of 110 mm with the spherical roller bearing having a 22 percent larger dynamic radial load rating than the tapered roller bearings. All tests were run at 165 percent of the respective two-row dynamic radial load ratings. The results show that both the indirect mounting (double cup or outer ring) and the direct mounting (double cone or inner ring) tapered roller bearings gave significantly better fatigue lives than the spherical roller bearings. These results appear to contradict the present ISO 281 standard which assigns a 1.15 b_m rating factor to spherical roller bearings compared to a b_m rating factor of 1.10 for that of tapered roller bearings.     

基于ANSYS的四列圆柱滚子轴承接触应力和刚度分析

对四列圆柱滚子轴承的接触应力、变形以及径向刚度进行了研究.建立了四列圆柱滚子轴承的有限元三维模型,基于ANSYS和Hertz接触理论,阐述了建模过程中的关键步骤,结合短应力线轧机的应用实例,计算了轴承滚子、内圈的接触应力与变形分布,直观表达了交错排列滚子之间的应力分布情况,计算结果和Hertz理论值相比较,具有较好的一致性.通过计算不同载荷下的轴承变形（轴承内孔轴线的相对位移）,获得了轴承刚度随径向载荷变化的规律.     

The lubrication of roller bearings subjected to couples

Roller bearings are generally designed to carry mainly radial loads with additional bearings employed to carry any axial loads. Occasionally, limited space prevents the use of these additional bearings, so that the roller bearing itself must carry the axial load. This must be taken by flanges on both the inner and outer races. The effect on the rollers themselves is to modify the load distribution on their generator contact surfaces because the rollers are now subjected to a couple in addition to the radial load. A similar effect is produced if two flanged (or unflanged) roller bearings support a loaded shaft. As its ends are nominally direction fixed, the rollers must be subjected to terminal couples, thus causing a modification to the load distribution at the contact surfaces. The effect of such forces on the footprint shape and on the bearing lubrication is investigated.     

双列调心凹面滚子轴承接触载荷分析

在考虑滚子与套圈、滚子与保持架以及保持架与引导套圈作用力的条件下,建立双列调心凹面滚子轴承动力学模型。以某双列调心凹面滚子轴承为研究对象,与静力学分析模型滚子最大接触载荷计算结果对比,验证了模型的正确性。并分析了工况条件(轴向载荷、径向载荷、倾覆力矩、转速)和结构参数(滚子数量、滚子长度、径向游隙)对滚子最大接触载荷的影响,结果表明:随轴向载荷增大,一列滚子受力增大,另一列滚子受力减小;随径向载荷增大,滚子最大接触载荷增大;随倾覆力矩增大,2列滚子接触载荷几乎不变;随转速增大,滚子最大接触载荷增大;随滚子数量增多和滚子长度增加,滚子最大接触载荷减小;随径向游隙增大,滚子最大接触载荷呈先减小后增大趋势。     

圆锥滚子轴承轴向载荷与预紧力矩的关系

研究圆锥滚子轴承在预紧状态下轴向载荷与预紧力矩及最小预紧力的关系.首先,对受载的圆锥滚子轴承的滚子进行受力分析,推导轴向载荷和滚子的内、外滚道,内圈挡边法向接触载荷的关系;其次,通过对滚动体的内、外滚道,内圈挡边的法向接触载荷与预紧力矩的分析,推导轴向载荷与预紧力矩的关系;并且,针对一对圆锥滚子轴承,讨论其轴向载荷与最小预紧力的关系.通过以上分析,最后得出圆锥滚子轴承在预紧状态下轴向载荷与预紧力矩的线性关系和最小预紧力的表达式.     

考虑轴箱轴承表面波纹度的高速车辆振动特性分析

采用SIMPACK动力学软件,建立一高速车辆出现轴箱轴承表面波纹度缺陷的动力学计算模型,将轴承假设为只有外圈和内圈两者之间的相互作用,轴承中的滚子直接等效成若干个力元,分别考虑轴承的内、外圈以及滚子表面波纹度对车辆振动特性的影响。仿真结果表明:当轴承出现波纹度缺陷时,轴箱振动加速度会增大,而构架的加速度变化不大;对于外圈表面波纹度,会在特定频率及其倍频处出现峰值,且当纹度波数等于或接近滚子数目相或其倍数关系时,轴箱会出现严重的振动;对于内圈表面波纹度,当波纹度数N_w≠iZ±1且N_w≠iZ±1(其中i为正整数)时,在所仿真的波数下可能会出现多种基频及其倍频成分,否则只会产生特定的基频及其倍频成分;对于滚子表面波纹度,当滚子波纹度数目为偶数时,只会出现特定的基频及其倍频成分,且在特征频率旁边存在着调制边带;随着滚子波纹度数目的变化,三种情况下的轴箱振动加速度幅值会在波纹度数目等于滚子数目处产生峰值点,且随着波纹度幅值的增加,三种情况下的轴箱的振动均变得越来越剧烈。     

Optimizing the Design of Cluster Mill Rolling Bearings

The design of back-up roll bearings in cluster-type rolling mills has, historically, been dictated by past engineering trial and error experience. Thus, to cause the bearings to act, as nearly as practicable, similarly to conventionally supported bearings, the outer ring section is usually made very heavy precluding large ring deflections.

There exists controversy among bearing manufacturers as to whether a bearing having many rollers of small diameter or one having a smaller number of larger rollers is best in this application. The study herein presented examines bearing life under each condition while fully accounting for the effect of outer ring deflection on fatigue life.

The investigation further demonstrates that an optimum design with regard to outer ring section thickness in relation to diametral size and number of rollers per row does exist with respect to bearing fatigue life. Whether such design is compatible with possible outer ring destruction due to heavy roll loads can only be proved by on-site testing.     

A New Form of Rolling Contact Damage in Grease-Lubricated,Deep-Groove Ball Bearings

A new form of rolling contact damage was discovered in the fatigue tests of series 6206 deep groove ball bearings under pure radial load with grease lubrication. The appearance of the damage reveals a few cracks at right angles to the rolling direction of the ball, along with the formation of a dent about 20 μ m deep in the raceway surface. This is found to occur only on the stationary outer ring raceway and the ball surface and is distributed widely within the load zone. Furthermore, under the raceway surface several cracks propagating into the substrate at an angle of about 60-80 degrees relative to the raceway surface are observed not only under the damage site but also in other nearby locations. Only the cracks at the damage position open up to the surface. The grease used for the test contained a lithium complex thickener with mineral oil as the base oil with a kinematic viscosity of 141 mm²/s at 40°C. On the test bearings two pure radial load levels of 9.14 and 12.13 kN were applied. In order to prevent the occurrence of seizure at each load, the speed of the inner ring of the test bearing was maintained at 1800-2500 min^{? 1} and 600-800 min^{? 1}, respectively, to keep the outer ring circumference temperature below 65°C. It is suggested that the damage is caused by metal-to-metal contacts due to lubricant starvation under grease lubrication and to a decrease in oil film thickness due to local increases in temperature.     

A Noise Analysis of Cylindrical Roller Bearings Operating Under Zero External Load

The purpose of this article is to numerically investigate one source of acoustic noise in roller bearings, that which results from the motion of the rollers in the bearing under zero external load. For the sake of simplification, it was assumed that the cylindrical roller bearings are infinitely long. Furthermore, the effects of the following on the noise of the bearing were also examined: the radial clearance of the bearing, the viscosity of the lubricant, and the number of rollers. The results of the study show that the fundamental frequency of the noise components of the cylindrical roller bearing corresponds to the multiplication of the number of rollers and the whirling frequency of the roller center. The acoustical frequency spectra of the cylindrical roller bearing are pure tone spectra, containing the fundamental frequency of the roller bearing and its superharmonics. The factors that decrease the sound pressure level of a cylindrical roller bearing include low lubricant viscosity, high radial clearance, and a reduced number of rollers. The results and discussions of the present article could aid in the design of low-noise cylindrical roller bearings.     

三排滚子转盘轴承的校核计算方法

针对现有转盘轴承在工程应用中所出现的滚道塑性变形、滚道疲劳剥落和套圈结构断裂这三种失效形式,利用转盘轴承的数值分析模型和有限元分析模型建立了联合载荷作用下三排滚子转盘轴承的校核计算方法。数值分析模型借助于变形协调条件和受力平衡条件解决了滚动体负荷分布的静不定求解问题;有限元分析模型将滚子简化为弹簧单元,而套圈仍然采用实体单元,避免了实体滚子与滚道接触的大量非线性数值求解计算。利用所建立的校核方法计算得出了滚道的抗塑性变形安全系数、滚道的疲劳寿命和套圈的结构强度安全系数,为判定该轴承满足给定应用工况要求的程度提供了依据。