Investigation On Turning Operation Of Slender Shaft

Due to the high length-to-diameter ratio of slender shaft,workpiece flexural deformation and vibration are frequently encountered during cylindrical turning of slender shaft. Thus, turning slender shaft is still a well-known difficult technical problem. Today, this problem is solved basically by empirical workmanship of the operator. This results in the fact that a demanding technical level of the lathe operator is essential for turning of slender shaft. And the productivity is very low. With the rapid development of science and technology,the demands for precision of mechanical parts are increasingly high. Efficiency and automatization of design and manufacture would be the inevitable tendency. Traditional machining methods cannot feed the needs in precision and efficiency. Under this condition,it becomes necessary to seek the breakthrough for solving the problem of turning slender shaft. Consequently ,it is very important to analyze quantitatively the influencing factors of flexural deformation and diameter error of slender shaft,and to probe approaches of minimizing the diameter error.Study on slender shafts turning processing is virtually researching the response of slender shafts with constant rotate speed under rotary and movable load. It is striving to do the further theoretic study on mechanism of slender shafts turning home and abroad. Due to the features of slender shafts i.e. weak rigidity and easy to cause vibrations, to control the vibration caused during slender shafts turning has become the linchpin and priority to improve the processing quality. This dissertation simplifies the supporting at both ends of slender shaft and builds forced model of slender shaft in the processing of turning and then builds free vibration equation without cutting force and excited vibration equation under cutting force on the base of the model. In addition, a lot of analysis and explanation were done for all possible vibration such as torsion vibration, radial vibration and axial vibration.With the help of the software of ANSYS10.0 that is powerful engineering finite element analysis applied software, this dissertation makes two kind of analysis: modal analysis and transient dynamic analysis. Converting the simulation data into graphics makes the simulation outcome clearer and pellucid. In the processing of turning, the natural frequency and vibration model of slender shaft are changed continuously, which leads to the complexness of vibration of slender shafts. This kind of complexness will be not find out if simple modal analysis is done, so it has been general trends to make research on the transient dynamics of slender shaft during the turning. Two feed ways of cutting tool are in common use in the processing of turning of slender shafts: obverse feed way and inverse feed way. This dissertation makes transient dynamics simulation analysis on both the feed ways under the same conditions and which feed way to select is provided by comparing simulation outcome of the two feed way. Analysis of deformed curve graphics proves the simulation outcome conforms to the actual status of turning, which provides a good start for simulation of turning of slender shafts on computer with the help of the software of ANSYS.