滚子分布方式对球面滚子轴承服役性能的影响
Effect of Rollers Arrangement Form on Service Performance of Spherical Roller Bearing

针对单纯考虑径向载荷难以综合评估滚子分布方式对球面滚子轴承服役性能影响的问题,以球面滚子轴承的滚子分布方式为研究对象,建立了能够表征滚子分布方式、自调心工况、转子挠曲以及外部载荷影响的数学模型。同时,编写程序对不同滚子分布方式,轴向、径向载荷以及自调心作用联合工况下的球面滚子轴承服役性能进行研究,从时域和频域两个方面解释了滚子分布对内圈振动的影响规律,归纳调心工况下特征频率的表达式,指出不同分布方式的滚子在联合工况影响下的载荷分布情况。另外,设计了能够在实验室单一环境下实现调心工况的自调心轴承座,选取两种不同滚子分布形式的22215型球面滚子轴承进行试验,并对理论仿真结果进行验证。结果表明:交错式滚子分布方式适用于径向载荷较大且调心作用明显的场合;平行式滚子分布方式适用于轴向冲击较大的工作场合;不论滚子交错分布还是平行分布,主频都约等于单列滚子数与滚子公转频率的乘积,当球面滚子轴承处于调心工况时,会产生附加频率,频率值约等于主频加、减滚子公转频率的整数倍;球面滚子轴承的调心功能本身会抵消由于转子挠曲带来的附加弯矩,但调心功能亦会造成滚子偏载,因此调心作用是以牺牲球面滚子轴承的承载能力为代价的。
For a spherical roller bearing (SRB), the effect of rollers arrangement form on SRB service performance cannot be evaluated objectively and comprehensively with only considering the effect of radial load in theoretical research. A mathematical model is hence proposed to characterize the rollers arrangement form, self？？aligning operating condition, rotor deflection and external loads simultaneously. SRB service performance is simulated and analyzed to obtain the effect of rollers arrangement form on inner？？ring vibration in both time and frequency domains, the empirical formula for expressing the characteristic frequency under the self？？aligning operating condition, and the rollers load distributions for different arrangement forms. A novel SRB pedestal is designed, which has the capacity to realize the self？？aligning operating condition in the laboratory, and two brands of SRB offered by different manufacturers are tested to verify the correctness of the theoretical results. The results show that the staggered arrangement form is recommended under the self？？aligning operating condition with huge radial load, while if the amplitude of the axial shock is large, the aligned arrangement form is a better choice. The characteristic frequency is equal to the number of the rollers in a single row times revolution frequency of all the rollers, no matter what kinds of SRB rollers arrangement forms are. Especially, some additional frequencies emerge due to the effect of SRB self？？aligning function, which equal the characteristic frequency plus/minus the integer multiples of the rollers？？revolution frequency. The bending moment accompanying rotor deflection can be offset by SRB self？？aligning function, which leads to unbalanced loading of SRB rollers. It means that SRB self？？aligning function is realized at the cost of reducing the carrying capacity