Dynamic Test And Analysis Of Critical Component Of Large-Scale Milling Machine

With the fast development of precision machine to high speed, precision and flexibility, In addition to requirement of machining have light weight, lower price, convenient to use, good processing property, the increasingly machining characteristics is also considered. The machining characteristics include the key parts of processing quality and chip efficiency, usually using the highest precision and surface finish that machined part could to be to evaluate processing quality, using metal removal rate or the max of cutting parameter to comment efficiency of chips. Then machining characteristics closely related to the dynamic properties, fact show that with the increasing requirement of machining characteristics, the requirement of dynamic properties is higher.This dissertation based on object of the large scale milling machine made of the Machining Group, exploring the effect of the dynamic properties of key parts.At the high speed, the key parts of milling machine appeared the vibration abnormal phenomenal, order analysis was done to the transmission system of the machine for this problem, proposed the work speed that the force vibration was corresponding to the first natural frequency, should be avoided when the machine works. When the machine worked at the high speed, vibration comes from the phenomenon of two gears'modulation.Used the experimental modal analysis of hammer experiment to test the key parts of milling body and milling head, obtain the natural frequency and modal shape of them, and propose the short comings and defect of them in structure. Used the ODS(Operating Deflection Shapes)and hammer experiment to tested the key parts of milling head and ram. Comparative analysis The results of ODS testing at different speed, one hand obtain the weakness links of them, the other hand get the virtues and defects, applicable situation of these ways, and improve the accuracy of the experimental modal analysis.Then used the software PRO/E to modeling the milling body, head and ram, and used the software ANSYS to analyzed theoretical modal of the structure, obtain the natural frequency and modal shapes of them, the error rate less than 15%, every modal shapes consistent with those, and propose the short comings and defect of them in structure, get the virtues and defects of two different ways.