基于双冲击的混合陶瓷球轴承剥落区宽度测量

发布时间：2018-03-25 00:13

本文选题：混合陶瓷球轴承　切入点：疲劳剥落　出处：《昆明理工大学》2017年硕士论文

【摘要】：混合陶瓷球轴承作为精密高速旋转机械中的一种重要支撑元件,被广泛应用于高速电主轴中,其故障为高速电主轴失效的主要形式之一。同常规滚动轴承类似,混合陶瓷球轴承的主要失效形式也是疲劳剥落。滚动轴承故障程度的大小可由剥落区宽度来反映,但对剥落区宽度的测量,目前可用的方法有限,通常只能将轴承拆卸后进行测量,操作不便。研究表明,滚道剥落故障的滚动轴承运行时,滚动体经过剥落区产生的振动信号具有双冲击特征,利用该特征可对剥落区的宽度进行测量,为实现运行工况下的滚动轴承状态评估和剩余寿命预测提供了可能。需要指出的是,振动信号中的双冲击特征比较微弱,又极易受到周围环境噪声的干扰,目前还没有一种比较有效的提取方法。此外,现有的基于振动信号分析的滚动球轴承剥落区宽度测量方法不仅需要采集振动信号,还需要采集实时转速信号,但实际工况下,受安装条件等限制,转速信号的获得不能得到保证,开展无转速计的剥落区宽度测量方法研究将有效增强其工程应用价值。本文以混合陶瓷球轴承为研究对象,开展了滚道剥落故障的振动信号的双冲击特征提取试验研究。该过程中,研究介绍了现代信号处理方法中的两种弱信号增强方法,基于AR模型的滤波方法和基于最小熵解卷积滤波的方法,并将其应用于双冲击特征的提取之中。结合谱峭度和Hilbert变换等包络提取方法,提出了一种利用谱峭度自适应去除优化频带外干扰信号的基于最小熵解卷积滤波的双冲击特征提取方法。试验分析结果表明,该方法可有效提取混合陶瓷球轴承剥落故障的双冲击特征。本文详细介绍了一种基于双冲击特征的滚动球轴承剥落区宽度测量的方法。该方法通过分析双冲击特征的形成机理,结合采集到的转速信号构建相关的双冲击特征间隔与剥落区宽度测量的理论计算公式,完成剥落区宽度的测量。但考虑到实际工况下转速测量不便等条件,文中提出了一种基于无转速计的剥落区宽度方法,该方法通过振动信号中整周期的冲击次数实现转速估计,结合平均双冲击特征实现了无需转速计的剥落区宽度测量,使该方法更适合于工程应用。试验结果表明,所提方法可对混合陶瓷球轴承剥落区宽度进行有效测量。
[Abstract]:Hybrid ceramic ball bearing, as an important supporting element in precision and high speed rotating machinery, is widely used in high speed motorized spindle. Its fault is one of the main failure forms of high speed motorized spindle. The main failure form of hybrid ceramic ball bearings is fatigue spalling. The extent of failure of rolling bearings can be reflected by the spalling zone width, but there are limited methods available to measure the spalling zone width. Usually, the bearing can only be measured after disassembly, so it is difficult to operate. The research shows that the vibration signal produced by the rolling body passing through the spalling area has double impact characteristics when the rolling bearing with the raceway spalling fault is in operation. The width of the spalling zone can be measured by using this feature, which provides the possibility for the evaluation of rolling bearing status and the prediction of residual life under operating conditions. It should be pointed out that the double impact characteristics in vibration signals are weak. At present, there is no effective extraction method. In addition, the existing measurement methods based on vibration signal analysis not only need to collect vibration signals, but also can be used to measure the spalling zone width of rolling ball bearings. It is also necessary to collect real-time rotational speed signals. However, in actual working conditions, the acquisition of speed signals cannot be guaranteed due to the limitations of installation conditions. The research of spalling zone width measurement without tachometer will effectively enhance its engineering application value. In this paper, the hybrid ceramic ball bearing is taken as the research object. In this paper, two weak signal enhancement methods in modern signal processing are introduced, and the double impulse feature extraction of vibration signal of raceway spalling fault is studied. The filtering method based on AR model and the method based on minimum entropy deconvolution filtering are applied to the extraction of double impulse features, and the envelope extraction methods such as spectral kurtosis and Hilbert transform are combined. A dual impulse feature extraction method based on minimum entropy deconvolution filter using spectral kurtosis to remove optimal out-of-band interference signals is proposed. The experimental results show that, This method can effectively extract the double impact characteristics of the spalling fault of hybrid ceramic ball bearings. This paper introduces in detail a method for measuring the spalling zone width of rolling ball bearings based on double impact characteristics. Combined with the collected rotational speed signal, the theoretical calculation formula for measuring the width of the spalling zone and the interval of the dual impact characteristic are constructed, and the measurement of the width of the spalling zone is completed, but considering the inconvenient measurement of the rotational speed under the actual working conditions, the measurement of the spalling zone width is realized. In this paper, a spalling zone width method based on tachometer is proposed. The speed estimation is realized by the number of shocks in the whole period of vibration signal, and the spalling zone width measurement without tachometer is realized by combining the average double impact characteristics. The experimental results show that the proposed method can effectively measure the spalling zone width of hybrid ceramic ball bearings.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH133.33

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