Wood-based Panels Broadband Sander Vibration Experimental Modal Analysis

Wood industry is a big user of the grinding machinery to sand belts all the time. However, in many years, in the region of production framework design, the domestic wood processing industry mainly considers its conservative properties of static intensity but does not pay attention to its dynamic characters, the result is that our science and research level of the dynamic characters is still in undeveloped state. In recent years, to meet the requirement of its future market, many domestic sander manufacturers are clearly aware of the vibration condition of its mechanical equipments relate to the quality and economical parameter of the processed things' precision, the lifetime of facility and productivity etc. Therefore, it's very important that we actively undertake our technological works of the machinery framework dynamic design.The Vibration and wave motion are basic states of material motion. With the rapid development of modern engineering technology, especially navigation, space flight and ocean engineering etc, the vibrating engineering technology got rapid development boom and comprehensive use. Modal analysis is a kind of modern way of the researching framework dynamics, which is not only an important method of the framework dynamic design and fault diagnosis of equipment, but also an application of the systematic discriminating method in the field of the vibration engineering. The experimental mode analysis technology is regarded as an important branch science of the vibrating engineering theory; its reliable test results have become effective standard evaluating production properties. Furthermore, according to its results, the ways of the playing various framework dynamic design, fault diagnosis and state monitoring have become important evidences in the field of the framework design.The thesis took wide belt sanders, two sides belts, model B229, made in shanghai JIECHENG BAIHE wood working machinery co., ltd, 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 and PSD 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. At last, the thesis made the conclusion, "the main reason of the horizontal lines limitation of MDF is the resonance phenomenon formed by coupling between its excitation frequency and its first class natural frequency." Meanwhile it put forward main suggestions namely framework dynamic modification including sensitivity analysis. The purpose is that set steady basis for the framework dynamic design works of the wide belt sanders with two sides belts in artificial board industry, and expect to create superior economical and social profit.