Abstract:

The thesis took wide belt sanders, belts four feet wide, two sides belts, model B229, made in China, as studying target. By means of the method of the framework dynamic design, beginning from its produced easily the horizontal lines defect to study its vibration characteristics and undertook respectively EMA (experimental modal analysis) and PSD(power spectrum density) to its sand shelf parts and whole machine etc. The modal test main takes cross spots testing method of fixed testing spots and alters the excitation vibration spots to result in its frequency response function of the fixed spots every excitation vibration spots, moreover applying SISO and taking advantage of frequency response function curve to modify completing mode parameter recognize so that getting its typical frequency response function chart of whole equipment and sand shelf part, as well as two classes mode shapes charts. It got sander's whole amplitude_frequency spectrums through PSD analysis and force frequency etc.

Key words: experimental modal analysis(EMA), power spectrum density(PSD), wide belt sander, dynamic design, frequency response function, modal parameter