Research On Dynamic Characteristics Of The Turning System

Cutting system including the machine tool, the cutter, the work piece and the cutting process is a complex dynamic system. The dynamic characteristics of a cutting system influence and constrain the reliability, safety, workmanship, efficiency and cost of the whole machining system. The dynamic characteristics of machine tool include the vibration, noise and thermal deformation in the operation status. For an ordinary machine tool, the vibration resistance and stability in cutting process are the most concerned. Cutting chatter often occurs in cutting process of the machine tool with bad dynamic performance, which would damage and disturb the normal cutting process. Recently as the machine tool is developed with the trend of high speed, high accuracy and high efficiency, dynamic characteristics of machine tool have been becoming increasingly demanding.CA6136machine tool was studied in this paper. The dynamic characteristic of machine tool was studied through theoretical and experimental methods respectively. The cutting stability analysis was taken into consideration through the cutting vibration test. The main contents of this paper are as following:Firstly, establish the finite element model of machine tool, then analyze the dynamic characteristic, and obtain the first six order natural frequency and the corresponding vibration mode.Secondly, dynamic test is conducted on the CA6136machine tool, its parameters of modal in the X and Y direction are acquired, and compared to the results of finite element method, which provides the dynamic design and accurate modeling with fundaments.Third, design and implement the experiment of cutting vibration, and identify the chatter frequency of cutting system. The active body of chatter is determined by finite element analysis and modal test of cutting system, which offers foundation for accurate modeling of machine tool to study the cutting stability.Finally, analyze the mechanism of regenerative chatter which most commonly occurs in cutting process, then establish the dynamic model of regenerative chatter, and illustrate the stability lobes of machine tool using the experimental data.