Dynamic Behavior of Long Turned Workpieces

One of the most important parameters used in the evaluation of machining technological systems is the dynamic quality, represented by the system stability and the specific feature of the reaction to the external factors, during the machining process. The dynamic quality of the machining system is given by the dynamic quality of the machine tool, cutting tool, cutting tool holding device, workpiece fixture. The dynamic behavior of the machining system is given by the stiffness of the elastic subsystem of the workpiece and tool. In the case that the deformation of the machine tool is small in relation with the two subcomponents of the technological system, mentioned, these can be studied separately. It is important to determine which is the weakest link of the technological system or to determine which is the component that can lead to the loss of the stability of the entire system. In the paper it is studied the dynamic behavior of the turned long, flexible workpieces. The workpieces are clamped in the lathes chuck and in the tailstock. The natural vibrational frequencies are determined according to a series of parameters as the diameter of the workpieces, axial forces applied by the tailstock.