Finite Element Analysis And Experimental Study Of The Column For NC Machining Center

In our country, most current structural designs of machine tools remain in sensible and experiential phase, which results in poor precision and reliability that cannot achieve the international level; it has greatly restricted the development of machine-tool industry.This thesis, based on the column of NC (Numeric Control) machining center, introduces FEM (Finite Element Method), which is in common use in structural analysis, into column's research and design. Firstly, some simplifications are made to part structures of the column, according to the structural characteristics of the NC machining center. Geometrical model is established in SolidWorks and translated into IGES file format, which can be imported into ANSYS easily. Finite element model is built up after following work: geometrical repair and perfection, determining the type of element and property of the material, restricting the boundary conditions, and meshing elements. Referring to static mechanics, three types of static operating conditions are simulated and static finite analysis is made after the loads are applied. According to the applicability of strength theory, first strength theory is chosen to check whether the strength is strong enough. Rigidity of the column is verified with the maximum displacement referring to the design accuracy. The first ten natural frequencies and corresponding modes are obtained from modal analysis. Based on the field strain testing, the distribution of the effective strains on the column is acquired, and a fast and practical method of field strain testing is put forward.The results of finite element analysis show that the column is of sufficient strength and insufficient rigidity. The results above are obtained by simulating the functioning of the maximum force loading on the column. Actually, under the limit operating condition, the counterforce produced by machining is far lower than the maximum load. The result of strain testing reveals that under the condition of normal processing even if the limit operating condition, the procreant strain is close to zero. Therefore, it proves that the actual rigidity of the column can meet most demands of processing.Finally, based on the theoretical analysis and experiments that have been done, the research subjects and direction for the future are indicated.