Research On Modeling And Influencing Factors About Bolt Joint Surface Of Heavy NC Machine Tool

As for the manufacture of advanced machine precision, complex machine tooldemand increasing, China has grown into the world’s largest machine tool market,the heavy NC machine tool manufacturing more and more attention in the processing.The processing performance of Heavy NC machine tool performance has afar-reaching impact on China’s manufacturing industry. The30%-50%static stiffness,more than50%of the dynamic stiffness depends on the combining part, and theinfluence on damping reached90%.Machine tool with the Department of static anddynamic performance directly determines the accuracy and reliability of Heavy NCmachine tool. Therefore, the research and design of machine tool with theDepartment of Heavy NC machine tool is very important.This paper investigated the domestic and foreign related to machine andmachine combined with the method of modeling the combined part of characteristicsof situation, from the Hertz contact theory, at the micro level to consider the contactsurface of the machine tool with form, and thus the machine combining face as avirtual material simulation. The Department of an arbitrary point is derived by usingthe Hertz theory of contact stress. We calculate the characteristic parameters of thevirtual materials and then use the ANSYS Workbench to solve the combined part ofthe natural frequency of the whole, the first five order modal extraction.Then this paper uses experimental modal existing techniques, mode of selectionscheme, through the selection of the scheme of the support mode, test points,incentives, combined the Department test signal parts, using parameter identificationmethod for a certain specimen of natural frequency and damping of the true value. Atthe same time, carries on the fitting to get two kinds of natural frequency. The naturalfrequency are compared with theory after establishment of a theoretical model, proveaccurate, can be used in heavy duty machine theory modeling, also shows that theformulas derived reliable virtual materials. Finally, we examined factors associated with the bolt pre tightening force, toolmaterials and processing methods influence the machine with the Department of thesize parameters of modified by kinetic model by using the theory of means. Weobtain the characteristics and rule of combination of Ministry of machine tool.