Analysis Of Influencing Factors On Static And Dynamic Characteristics About Beam Combination Part Of Heavy Longmen Machine Tool

In the face of the current manufacturing equipment industry continues to grow,the demand for high quality and high efficiency precision machine tool is increasing gradually,at the same time,heavy machine tools in China's power,aerospace,large ships,and many other areas are also particularly important to become an indispensable factor.Found in the study,beam combination part of heavy Longmen machine tool with large size and non uniformity,so the influence on the performance of the whole machine is the most obvious.The influence of the combination part on the machine tool is realized as the more than 90%damping and 50% of total flexibility,50% of the dynamic stiffness and 30%-50%static stiffness.Because the contact form of the combined part is more complicated and it is difficult to simulate its real situation,reserch on improvi ng the overall performance of the machine tool is at a standstill,at the same time,Heavy Longmen machine tool is an important part of the national strategic reserve materials.So it is important to reserch on beam combination of Heavy Longmen machine tool.Therefore,we need to in-depth study of the combined part in order to predict and optimize the performance of machine tool.In this paper,the research on the beam combining parts of heavy Longmen machine tool is as follows:At first,reserch on both here and abroad related to machine and machine combined,application of Hertz theory and research on the micro contact form of the contact surface,so as to put forward the modeling method of virtual gradient material layer.The method is based on the assumption that there is a layer of virtual material in the combined contact surface,with the same size of the combination,and considering the large size of the joint part of the beam,the virtual material is not uniform.According to the actual data of the machine tool,the formula of characteristic parameters of the virtual gradient material layer is derived.On the basis of this calculation,the specific numerical value of the beam combination part is calculated,using ANSYS Workbench to analyze and solve.Then the experimental modal analysis technique is used to verify the theoretical value.Experiments are designed to fit the large size joint part of the beam,select the reasonable test location and incentive points.Then extracting the test signal and parameterizing them to get the true frequency.Comparison of experimental data and theoretical data,using error formula to get calculation error.It is accurate of virtual gradient material layer modeling method after determining the error in a reasonable range.At last,according to the virtual gradient material layer method,modify the material of the combined part,machined surface roughness,initial surface pressure to analysis of the characteristics and laws.