Study On The Grinding Vibration And The Structure Dynamics Of M1432A Cylindrical Grinder

Grinding is a process method of making abrasives rotate rapidly in order to cut excess material of the workpiece. Under normal processing conditions, grinding accuracy can reach IT5-IT6 level, even higher than IT5 level, and surface roughness is Ra0.32～Ra1.25μm. With a variety of high hardness materials being used increasingly and continuous improvement of the grinding process, the use of grinder is expanding and the proportion in the machinery manufacturing industry is rising. Grinding process of a country level has become an important indicator of the level of the country machinery manufacturing. However, the vibration of grinding seriously affects the machining accuracy and surface quality of work piece. So the vibration during grinding need studying in order to explore practical approach to improve parts precision and the efficiency of processing.The grinding principle, the basis of vibration theory, nonlinear vibration and finite element theory and methods are introduced in detail. With M1432A cylindrical grinder as the research object, considering the external grinding force as the excitation, two degree freedom non-linear vibration of external grinding model is established. The bifurcation diagram, track curve and poincare mapping are obtained by means of MATLAB software. The effect of circumrotation velocity on the non-linear vibration characteristic of the system is analyzed. The results show that circumrotation velocity should not approach or equal to the intrinsic frequency of the non-linear vibration system so that the system avoids being in the state of chaos or mimetic periods. When grinder being at the stage of starting and stopping or grinding speed closing to the natural frequency, the motion state of the system is unstable and the quality of workpiece surface declines seriously. So the grinder should be avoided in such state of motion. The modal analysis about grinding wheel spindle body frame of M1432A cylindrical girder are explored finally, SolidWorks is used to complete the three-dimensional mathematical model of the relevant parts. Simulation is used in solving the finite element analysis about wheel spindle body frame and the first 12 vibration modes of wheel spindle are obtained. By analyzing the frequency of the greatest impact on the vibration, some effective control measures is proposed in order to improve the manufacturing accuracy and surface roughness.