轴承的游隙及游隙的选择

介绍了影响轴承游隙的因素和典型使用情况下轴承游隙的选择原则及游隙对轴承寿命的影响.     

气体静压小孔节流与多孔质节流性能的比较

本文给出了传统的小孔节流和多孔质节流轴承的理论分析，分析了外部供压气体轴承的进气形式对轴承性能的影响，对于不同类型的小孔节流和多孔质节流的轴承，本文给出了实验结果，并对轴承的性能参数即承载能力，刚度等进行了比较，作者分析了小孔节流和多孔节流止推轴承的承载能力和刚度，结果表明多孔质止推轴承同小孔节流轴承相比，具有高的承载能力。     

含铅量对Fe-Pb-3Cu系含油轴承性能的影响

在含油轴承试验机上，通过对Fe-Pb-3Cu系列含油轴承运转时的摩擦系数和温升等性能参数的试验测试对比，讨论了含铅量对Fe-Pb-3Cu系列含油轴承性能的影响。试验结果表明，在不同含铅量的四种Fe-Pb-3Cu系含油轴承中，Fe-20Pb-3Cu含油轴承的摩擦性能为最好。这就说明在Fe-Pb-3Cu系含油轴承中，含铅量太大和太小都对含油轴承的性能不利，只有当含铅量达到一个恰当的值时，含油轴承的摩擦性能才能达到最佳。     

新型空心圆柱滚子轴承振动试验

介绍一种滚动轴承振动卧式测量方案,并运用该方案对新型空心圆柱滚子轴承和实心圆柱滚子轴承的振动性能进行了对比分析,结果表明,在一定条件下,新型空心圆柱滚子轴承的振动性能优于实心圆柱滚子轴承.     

Effect of operating parameters on the threshold voltages and impedance response of non-insulated rolling element bearings under the action of electrical currents

In the present work, the effects of operating parameters on the threshold voltages and impedance response of non-insulated rolling element bearings under the influence of varying levels of electrical currents have been studied. The voltage-current relationships in the bearings have been established.Investigations reveal that first and second threshold voltages appear under the influence of electrical currents in the bearings, depending on the lubricant resistivity, oil film thickness, bearing conditions and the operating parameters. The detected threshold voltages are primarily responsible for momentary flow of current and the further increase in current intensity with a slight change in potential drop across the bearings. The impedance of the bearings becomes negligible as the current intensity across the bearing increases. However, the impedance is more affected by the speed and film thickness than by the load on the bearings.This paper highlights the mechanism of the process of failure of the bearings, using lubricants with different characteristics. The investigations show that the experimentally evaluated threshold voltage coefficients of the bearings, using high resistivity lubricants, increase with speed and are independent of the loads on the bearings. This behaviour of the threshold coefficients of the bearings is used to predict the threshold voltages at different parameters of operation. However, bearings using low resistivity lubricants do not display the threshold voltage phenomenon.The investigation may also be used to determine the safe levels of potential drop across the bearing elements, to avoid damage of the bearings under different operating parameters and also to assess the film thickness by the measured impedance and current intensity response of the bearings.     

Effect of fluid film wave bearings on attenuation of gear mesh noise and vibration

The attenuation of the gear mesh noise/vibration by fluid film wave bearings relative to rolling element bearings was experimentally investigated. Tests were performed on a gearbox that can accommodate both rolling element bearings and wave bearings. It was found that at specific speeds and torques, the wave bearings could significantly reduce the noise/vibration compared to rolling element bearings. Because the gear noise is accompanied by noise from other sources, a method was developed to extract from the original signal only the mesh harmonic components.The wave bearing dynamic coefficients were also predicted. It was found that adjusting the wave bearing parameters could considerably increase the capacity of the wave bearings to attenuate the gear mesh noise and vibration.     

陶瓷球轴承内部结构参数优化设计及其性能试验研究

氮化硅陶瓷是一种较好的滚动轴承材料,在此提出了陶瓷球轴承内部结构参数优化设计的基本原则,建立了其优化设计的数学模型,通过对钢球轴承和陶瓷球轴承的性能对比试验,证明了陶瓷球轴承的高速性能要优于钢球轴承,并验证了陶瓷球轴承优化设计原则。     

铁路货车等级轴承一般检修工艺的设计

对货车352226X2D1-2RZ第1等级滚动轴承与352226X2-2RZ原型轴承的结构和检修限度进行比较,对第1等级轴承检修工艺中的尺寸检测、轴向自由游隙测定、注脂及等级轴承与车轴轴颈压装工序进行分析,设计了第1等级轴承一般检修的最佳工艺方案,并针对等级轴承在车间现场一般检修时易出现混装问题,提出了有效的工艺控制措施。     

Severity Estimation of Cracked Shaft Vibrations within Fluid Film Bearings

The equations of motion, with four degrees of freedom, taking into consideration the flexibility, damping and cross coupling of the fluid film bearings are derived for a cracked Jeffcott rotor supported on fluid film bearings.

Dimensionless equations are developed for dynamic radial load, dynamic pressure developed in the fluid film bearings and coefficient of dissipation considering the journal vibrations in two harmonics; bearing fluid film stiffness and damping coefficients. These are applied to a cracked Jeffcott rotor supported on different types of bearings, i.e., cylindrical journal bearings, offset cylindrical bearings, tilting pad journal bearings and three-lobe bearings. Based on the allowable dynamic pressure developed in the fluid bearings, the severity of cracked shaft and allowable crack depths are estimated in this study. Measurement of dynamic pressure and dissipation for monitoring the crack growth is suggested. However, 2x vibration is the best indicator of cracks in the shafts.     

A review on the preload technology of the rolling bearing for the spindle of machine tools

The performance of the spindle system and bearings in a machine tool is largely influenced by the preload applied to bearings. Therefore, it is a very important issue to determine a proper preload in bearings and apply it to bearings for satisfying the performance required in bearings according to its operation conditions. This study performed a review on the preload technologies through classifying these technologies into three categories; a preload configuration technology that properly determines the preload for optimizing the performance of bearings, a preload application technology that applies the determined preload to bearings during the operation of a spindle system as a reliable way, and a preload measurement technology that verifies the preload applied to an actual spindle system.     

涡轮泵流体静压轴承设计及性能特性分析

针对流体静压轴承在液体火箭发动机涡轮泵中的设计和应用,以现有的滚动轴承支承的涡轮泵转子为应用对象,提出流体静压轴承的参数设计思路,采用粒子群优化算法设计得到支承刚度最大化的轴承结构参数组合,并计算分析所设计轴承的性能以及轴承-转子系统的动力学特性。分析表明：优化设计得到流体静压轴承的承载力和支承刚度可以满足要求,但轴承总流量达泵流量的21%,这会显著降低涡轮泵的总体效率;仅将滚动轴承改为流体静压轴承,而不改变其他结构或布局,转子的稳定性不能满足要求;涡轮泵流体静压轴承转子系统设计时应尽量将轴承布置在转子位移较大的位置,以充分发挥其阻尼作用。     

风电主轴调心滚子轴承中挡边结构对其性能的影响

以三点支承风电机组传动系统主轴用双列调心滚子轴承为研究对象,介绍了固定中挡边、浮动中挡边、无中挡边3种挡边结构轴承,基于风电主轴轴承典型工况,建立轴承动态分析模型,分析中挡边结构对轴承轴向位移、PV值、滚子偏摆、摩擦功耗的影响.分析结果表明,固定中挡边轴承刚性好,轴向位移小,PV值小,滚子姿态稳定,滚道摩擦功耗低,性能...     

平箔式箔片止推气体轴承静特性的理论研究

根据平箔式箔片止推轴承的结构。导出了求解箔片止推气体轴承特性的方程。利用有限元法进行了数值求解。比较了箔片止推轴承与刚性轴承的不同之处，并讨论了影响箔片止推轴承特性的因素。     

Fundamental dynamic performance of fluid-pivot and squeeze-film damper bearings

Due to the increase in rotational speeds and performance of modern turbomachinery the rotordynamic stability of such machinery has reduced. In order to improve rotordynamic stability, fluid-pivot and squeeze-film damper bearings have been developed. By using a simple analytical model to predict the unbalance response of a single mass rotor and by modelling the above bearings as a two-mass-spring and damper system the fundamental performance of these types of bearings has been determined. The results are that these bearings can significantly improve rotordynamic performance over a certain frequency range. This is mainly due to the ability of these bearings to reduce the effective bearing stiffness and hence improve the damping efficiency of the bearings. These auxiliary damped bearings increase the bearing damping efficiency rather than increase the bearing damping.     

圆锥滚动轴承外圈制造工艺改进

圆锥滚动轴承的套圈是重要的承载部件,对轴承的性能有着重要的影响。圆锥滚动轴承的套圈大都采用传统的热锻造加工工艺,这种工艺存在很多缺点,影响轴承的性能。文中讨论了一种冷辗扩成形工艺,能有效地节省材料和能耗,提高套圈精度,从而提高轴承的使用寿命。     

机器人用四点接触球轴承旋转精度影响因素

针对机器人用四点接触球轴承旋转精度难以预测和控制的问题,提出了同时考虑轴承内圈沟道和外圈沟道圆度误差的轴承旋转精度数值计算方法。根据轴承内部元件运动学和几何学关系建立轴承旋转精度数值计算模型。使用MATLAB编写轴承旋转精度求解程序,得到内圈沟道圆度误差幅值和谐波阶次、外圈沟道圆度误差幅值和谐波阶次、钢球直径偏差及钢球个数对轴承旋转精度的影响规律。进行了轴承旋转精度试验,验证了仿真结果的正确性。轴承旋转精度涉及很多指标,所研究的四点接触球轴承旋转精度衡量指标指轴承外圈径向跳动。结果表明:轴承外圈径向跳动随着内外沟道圆度误差幅值的增大先平稳后快速增大,随着内圈外沟道圆度误差谐波阶次的增大呈现周期性变化,随着钢球直径偏差的增大呈线性减小,随着轴承内部钢球个数的增大呈指数减小。所建模型解决了四点接触球轴承旋转精度难以进行理论求解的问题,能够准确预测轴承的旋转精度,为四点接触球轴承的精度设计提供了理论基础。     

改进的变渗透度含油轴承

本文介绍了作者研制的一种沿圆周方向和半径方向均变渗透度含油轴承，与以往的变渗透度含油轴承相比，其内部结构更为合理，其高低渗透度区过渡平缓，应力集中得到缓和，在制造和使用过程中不易破裂。理论分析与实验研究均表明：与普通含油轴承相比，其性能更为优越。     

Tribological behavior of frictional seismic dampers of pendulum type

Frictional pendulum bearings have universal properties that can meet various requirements at service of buildings, bridges, and industrial constructions. The formulas for the average dimensionless wear rate and friction coefficient of the bearings are obtained. The use of the bearings as seismic dampers of shell drilling rigs is described and characteristics of the frictional pendulum bearings are given.     

Contact mechanics and lubrication analyses of ceramic-on-metal total hip replacements

Ceramic-on-metal (CoM) total hip replacements have shown reduced wear and friction. Lubrication and contact mechanics analyses play an important role in providing an overall understanding for the tribological performance of CoM bearings. In the present study, the steady-state contact mechanics and elastohydrodynamic lubrication (EHL) and transient EHL of CoM bearings were analyzed. The dry and lubricated contact pressures of CoM bearings showed typical characteristics of hard-on-hard hip bearings. The effects of head radius and radial clearance on the lubrication performance were predicted. CoC and CoM bearings are more likely to benefit full fluid film lubrication than MoM bearings.