Research On Vibration Reduction Performance Of Deep Processing Boring Bar

With the rapid development of modern science and technology, the demand for mechanical processing is becoming higher and higher. While in China, the technology of vibration reduction for processing of deep hole is far lagging behind developed countries. The boring bar of large ratio of length to diameter as the main machining tools of deep hole will direct the development of the technology of deep hole machining. One of the reasons of research progress in technology of boring bar of large length to diameter ratio slowly is insufficient understanding to the main parameters affect vibration. Starting from this issue, this paper will study the main factors affect vibration of large length to diameter ratio of boring bar.Firstly, this article has conducted the modal analysis which based on the slender cantilever bar instead of boring bar, then got all order resonance frequency which happened under great deformation position, and completed the vibration simulation analysis, then get the longest overhanging place which have major amplitude occurred in the fundamental frequency. According to the fundamental frequency of the vibration mode, I add a dynamic absorber in the longest overhanging place, and establish theoretical model, then get several important factors which affect the damping effect.Secondly, with the theory of deflection of cantilever, I analyzed the influence of vibration of the boring bar with cavity diameter and length of boring bar and ultimately determine the cavity diameter and length of the boring bar of this study. And according to the kinetic theory of damping boring bar, I solved the main parameters of vibration absorber of boring bar and did a simulation and comparative analysis of parameters.Third, I did modal analysis and frequency response analysis of the boring bar by using the method of simulation of finite element. On the basis of simulation of the modal, I analyzed the frequency response of the damping boring bar inspired by the external world in certain frequency range. Then I analyzed the influence of the main parameters of vibration absorber of boring bar to the vibration of damping boring bar. Finally, experiments are carried out to verify the above simulations. According to the principle of metal cutting, I established the relationship between cutting parameters in the actual machining and the force of boring bar. According to relationship between the force of boring bar in the actual machining by finite element simulation and vibration of boring bar, I studied on the influence of cutting parameters on the boring bar vibration and made experiments for the above simulations to verify the correctness of the theoretical analysis.