圆锥滚子轴承保持架扩张凸模

扩张是用模具强迫保持架局部直径变大,以利于装配时滚子、内圈放入的一道工序。要求保持架在最小变形范围内以最小的扩张量使滚子产生最大的径向外移。 图1为扩张前的保持架、滚子及内圈相互位置关系图,内圈被滚子C点限住。滚子AC部分应向外移,内圈方能装入,所以保持架EB部位就应是扩张部位。凸模在冲床     

圆锥滚子轴承筐形保持架的改进

针对单由滚子引导的圆锥滚子轴承筐形保持架窗孔过长,轴向、径向窜动量大,造成轴承噪声和振动较大的问题,通过在内圈挡边与保持架之间压配1个消声环,利用滚子和内圈挡边共同引导保持架,有效地降低了轴承噪声。     

圆锥滚子轴承振动值分析

利用正交试验 ,通过改变工序中不同的参数 ,寻求降低轴承装配后振动值的措施 ,降低滚动面的粗糙度值对振动值影响显著 ,保持各工序的稳定 ,消除磕碰伤是降低振动值的保证。附表 4个。     

圆锥滚子超精若干问题探讨

全凸滚子超精有三段式和平直式两种方法,平直式是目前国内较普遍采用的方法。论述了平直式和三段式的加工原理及提高平直式超精辊使用寿命的方法。附图６幅。     

降低圆锥滚子轴承振动噪声的探讨

通过对LM11949／10、NU211等轴承零件作单因素交叉试验和对国外同型号产品振动对比分析,找出了圆锥滚子轴承诸零件对轴承振动的影响规律,尤其是找出了滚子波纹度是影响轴承振动加速度和振动速度高频档的主要因素。通过两项企标实施和采取降振措施,收到了明显效果。附图2幅,表5个。     

圆锥滚子轴承滚动体的凸度分析

圆锥滚子轴承的修型技术是使用带凸度的滚子以避免或降低滚动体和内外圈接触引起的边界应力集中。采用ANSYS软件对圆锥滚子不同凸度下的应力情况进行分析。分析结果表明,在一定的条件下带凸度的圆锥滚子1轴承可以最大限度的降低滚动体和内外圈接触引起的边界应力集中。     

圆锥滚子轴承的改进

本文介绍了圆锥滚子轴承的结构特点,在选择材料、制造、设计等方面的改善与创新．圆锥滚子轴承现在可以在高速和高精度的场合下广泛使用，并且轴承尺寸减小，承受负荷能力增大。     

Rolling Element Skew in Tapered Roller Bearings

This paper reports on the roller skew in tapered roller bearings monitored by contact potential difference probes. The effect of the load, rotational speed, and viscosity of lubricant on roller skew angle, along with the variation of bearing torque with the running conditions, were measured on a LM501300 bearing. Two greases (SHC15 and SHC460) were used to lubricate the bearing. The skew angles were found to vary from 0.15° to 0.6°. The results indicate that the skew angle depends on the friction force at the roller-rib interface. An empirical equation is derived which relates the skew angle to the bearing operational parameters.     

Prediction of Roller Skewing in Tapered Roller Bearings

The paper proposes a comprehensive model to predict the skew movement of a roller in tapered roller bearings. Numerical solutions are given on a LM48548/LM48510 bearing. The effect of the shaft speed, ring misalignment, and lubricant temperature on the roller skew angle is presented and compared to the experimental data available in the literature. The results indicate that the skew angle depends first on the misalignment angle between the cup and the cone. The roller skew is also greatly influenced by the traction at the roller-flange contact, the skew angle increasing with the traction at this contact, and by the geometry of the roller end.     

Thermally-Induced Failures in Railroad Tapered Roller Bearings

An Association of American Railroads (AAR) class F (6 1/2 × 12) tapered-roller bearing assembly is modeled, using finite elements, to examine thermally-induced failures observed in the laboratory when the bearing is operating at relatively high speeds. It is hypothesized that this failure is caused by an unstable thermal expansion/internal bearing load feedback process. Sequentially-coupled, transient thermal and static structural models are used to obtain the thermal-mechanical transient time response as a function of speed, seal type, and lubricant starvation at the rib contact. The model assumes no external loads and zero initial preload (zero end-play). Therefore, the loads developed in the bearing are thermally-induced and self-equilibrated. Two train speeds, viz. 80 and 100 mph, are considered. Simulation results indicate that at axle rotational speeds equivalent to a train speed of 100 mph, a combination of grease starvation and heat flux from the contact seals cause high rib temperature and subsequent unstable load growth which will lead to failure. At rotational speeds equivalent to train speeds of 80 mph or for bearing assemblies that utilize special design seals, the rib temperature is relatively low and no operational instabilities were observed for the model used.     

Analysis of Surface Parameters and Vibration of Roller Bearing

The surface of the inner race of a detachable roller bearing is monitored periodically to determine the deterioration pattern under normal conditions together with the vibration level. The surface of the inner race is scanned using an infinite focus microscope to evaluate surface properties utilizing the 2D and 3D parameters. Both parameters successfully assess the surface degradation and wear of the bearing surface. Using the Dowson-Higginson equation on elastohydrodynamic lubrication, the theoretical lubrication film was calculated and the lubrication regimes identified. A high vibration level can be associated with surface roughness properties and relative lubrication regime. This work highlights the relationship between the bearing vibration level and the bearing inner race surface parameters. The two surface parameters with the highest Pearson correlation coefficient with the vibration level are the areal surface roughness S_a (0.997) and the average roughness R_a (0.936).     

The Effect of Adapter Crown Wear on Rated Fatigue Life of a Railroad Tapered Roller Bearing

A model is developed to describe the effects of adapter crown wear on the misalignment of a railroad tapered-roller bearing. Wear of the crowned surface results in a flat on top of the adapter. This flat, in contact with the wear plate, is shown to have the capacity to transmit a moment between the bearing and the side-frame of the truck. The magnitude of the moment transmitted is dependent on the length of the flat. These analytical results are coupled with model results from a bearing manufacturer, which give the relationship between bearing misalignment, and thus transmitted moment, and reduction in fatigue life of the bearing. The analysis indicates that a slightly worn adapter has no appreciable effect on the rated fatigue life of the bearing, but once a threshold level in adapter crown wear is reached, the bearing fatigue life will begin to decrease. Large amounts of adapter crown wear will result in significant bearing misalignment and a corresponding reduction in the fatigue life of the bearing.     

圆锥滚子端面侧摆智能检测系统

圆锥滚子基准端面摆动SDW(端面侧摆)是圆锥滚子轴承的一项重要质量指标.介绍的圆锥滚子端面侧摆智能检测系统,符合圆锥滚子轴承检测规程要求,可以实现圆锥滚子端面侧摆自动检测和自动分拣.依据多传感器数据融合原理的多周期检测数据融合处理方法,对滤除采样中的干扰信号、提高端面侧摆检测的准确性均十分有效.该系统已经过实际应用验证并获得国家专利.     

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.     

高速铁路客车圆锥滚子轴承滚子的凸度分析

以高速铁路客车圆锥滚子轴承为研究对象,采用有限元法研究不同凸形和凸度量对滚子与滚道之间接触应力及应力分布的影响,通过计算分析确定圆锥滚子轴承滚子合理的凸形和凸度量。分析结果表明,对数母线型滚子和合理的凸度量能降低滚子与滚道接触引起的边界应力集中,而且一定的载荷都会对应一个较优的凸度量区间,凸度量过大或过小不但没有降低边界应力集中,反而会引起滚子端部和中间的应力差值,减弱滚子沿轴线方向应力分布的均匀性。     

牙轮钻头滚动轴承的失效分析及延寿措施

本分析了牙轮钻头滚动轴承的失效形式,从改进系统结构设计,采用新型结构、新型材料和表面强化拱么及提高轴承系统的加工质量等方面阐述了提高该类型轴承寿命的措施。     

高频破碎器调心滚子轴承失效分析

调心滚子轴承是高频破碎器的关键部件,其好坏直接影响着高频破碎器的使用寿命。通过粗视检查及有限元仿真对高频破碎器上调心滚子轴承的失效原因进行分析,结果表明其失效主要是由于冲击载荷过大造成的。一方面,大冲击载荷造成了调心滚子轴承的内、外圈和滚子变形,导致轴承受力不均发生偏载而卡死;另一方面,大冲击载荷使轴承内部油膜破裂,造成金属之间的相互摩擦,轴承温度急剧上升而发生咬粘失效;最后,根据调心滚子的失效原因提出了相应的改进措施。