Abstract: In this paper, some dynamical tests are made for a bearing assembly in preload and non-preload and different nonlinear features of both states of the bearing assembly are detected. The analysis methods of bispectrum and zoom bispectrum are discribed. The fast estimating formulas of bispectrum are developed. The test results of the bearing assembly are analysed by means of bispectrum and zoom bispectrum methods. Finally, we obtain some important conclusions about the bearing assembly.

Key words: 动态试验, 非线性, 组合轴承