基于双冲击现象的混合陶瓷球轴承剥落区长度测量及剩余寿命预测

Hybrid ceramic ball bearings are widely employed as the key support parts of the electric spindles in high-speed cutting tools. However, the failure detection and the remaining useful life prediction theories for hybrid ceramic ball bearings in the operating conditions have not been well studied. Based on the internal relations between the spall length of the faulty rolling element bearing and the double impulses phenomenon, the project is dedicated to study the hybrid ceramic ball bearings spall size measurement and the remaining useful life prediction theories and approaches. The main contents include: 1) Double impulses feature extraction. The bearings' incipient faults corresponding vibrations are analyzed by the spectral kurtosis and the blind source separation algorithms to develop an effective extracting approache for the double impulses phenomenon generated by the spall in a noisy condition. 2) Mechanism and modeling of the double impulses phenomenon. Based on the Hertz contact theory and the double impulses phenomenon, the dynamic contact relationship between the spalled surface and its corresponding contacted surfaces will be investigated. The corresponding mechanism will be exploited to build a reasonable dynamic model for hybrid ceramic ball bearings which can be employed to explain the double impulses phenomenon. 3) Spall length measurement. The relationship of the rotating speed, the spall length and the bearing size etc. will be studied to develop the spall length measurement theory and the spall length estimating formula with the double impulses phenomenon. 4) Remaining useful life prediction. By taking the derived spall length measurement as the evaluation of the performance degradation of hybrid ceramic ball bearings, we will establish an improved remaining useful life prediction method based on observer theories. Finally, the hybrid ceramic ball spall length measurement approach and the corresponding remaining useful life estimation method under the operating conditions will be achieved.

混合陶瓷球轴承已成为高速切削机床电主轴的重要支撑部件，但目前针对其运行工况下的故障失效检测和剩余寿命预测相关理论及方法不多。项目基于滚动轴承剥落损伤对应的双冲击现象与剥落区长度的内在联系，开展混合陶瓷球轴承剥落区长度测量及剩余寿命预测研究有重要意义，内容包括：1）双冲击特征提取。基于谱峭度、盲源分离算法研究干扰条件下轴承初期故障对应双冲击特征分量的准确提取方法；2）双冲击现象机理建模。基于Hertz接触理论和双冲击现象，研究剥落面与其接触面间的动态接触关系，建立包含表面剥落损伤对应双冲击现象的混合陶瓷球轴承动力学模型；3）剥落区长度测量。研究双冲击现象随转速、剥落区长度及陶瓷球尺寸的变化规律，推导基于双冲击现象剥落区长度估计理论公式；4)剩余寿命预测。增添剥落长度测量结果为评价指标，基于观测器理论建立其剩余寿命预测方法。最终获得适合运行工况的混合陶瓷球轴承剥落区长度测量及剩余寿命预测方法。

混合陶瓷球轴承为高速切削机床电主轴的重要支撑部件，但目前针对其运行中的故障失效检测和剩余寿命预测相关理论及方法不多。项目基于滚动轴承剥落损伤对应的双冲击现象与剥落区长度的内在联系，开展混合陶瓷球轴承剥落区长度测量及剩余寿命预测研究有重要意义，主要研究内容包括：1）双冲击特征提取。基于谱峭度、盲源分离等研究干扰条件下轴承故障对应双冲击特征的准确提取方法；2）双冲击现象机理建模。基于Hertz接触等理论，建立包含表面剥落损伤对应双冲击现象的混合陶瓷球轴承动力学机理模型；3）剥落区长度测量。研究推导基于双冲击现象的剥落区长度估计理论公式；4)剩余寿命预测。建立剩余寿命预测方法。.本项目的开展已取得以下重要成果：1）基于Hertz接触理论，结合运用运动学、动力学理论建立内外圈剥落故障双冲击特征机理模型，该机理模型的建立对合理诠释双冲击现象及后续的深入研究有重要的理论学术价值；2）提出了一种基于共振解调包络提取和独立分量分析的高鲁棒性滚动轴承特征分离方法，实现了多冲击干扰源情况下包络的按源分离提取；3）提出了一种基于EEMD的双冲击特征提取方法，实现了对双冲击特征的提取和间距测量；4）试验研究中在混合陶瓷球轴承剥落故障的声发射信号中观察到了双冲击特征，为双冲击现象的研究开辟了新途径；5）提出了一种可用于声发射双冲击特征提取的分离处理方法；6）提出了一种基于约束独立分量分析的滚动轴承包络提取方法，可在多冲击干扰源情况下对选定特征包络特征的分离提取；7）提出了一种基于冲击特征的无转速计剥落区宽度估计方法，实现了无需转速计的剥落区宽度估计；8）研究了一种基于神经网络和主成分分析特征指标缩减的滚动轴承性能退化预测方法。.本项目的研究已达到预定目标，针对混合陶瓷球轴承剥落故障对应振动的双冲击现象，探索提出其产生机理模型等新知识，发展了特征提取、检测方法等，对今后开展该领域的相关研究有较好的学术价值及潜在的工程应用前景。