Study On Feedrate Scheduling For Cutting Force Regularization

As a machining technology with high quality and efficiency, High Speed Milling (HSM) is playing a more and more important role for the development of modern mechanical manufacturing industry. Ordinary high speed spindle speed and large feedrate are always adopted in HSM process. Thus the quality of workpiece is extremely sensitive to the cutting force undulation. Therefore, studying on the effective technology of cutting force regularization, on one hand, is helpful to plan the process appropriately in HSM, on another hand, enable the machine to exert fully the processing performance, which can contribute to the improvement of processing quality and production efficiency.In traditional contour milling, the typical contour parallel offset cutter allowance and constant feedrate are adopted. However, during the machining process, the contour of workpiece is usually curve and complex, which makes the cutting condition change frequently and leads to the undulation of cutting load that affects the machining quality. As to the method of feedrate setting, usually the feedrate of the worst cutting condition is adopted as the feedrate of whole cutting process, which cause the ability of cutter and machine tool can't be used sufficiently and the machining efficiency was pressed. Therefore, this paper presents a cutting force model which is the function of cutter engagement arc and equivalent feed rate through analyzing the main factors to affect the cutting force in HSM and researches on the feedrate adjustment method based on the cutting force model. Combining with the idea of steady cutting force allowance for HSM, this paper presents a machining method with constant cutter engagement arc and constant cutter contact points velocity for HSM. This method can make the cutter engagement arcs steady by optimizing the machining remainder and adjust the cutter location feed rate with concerning the figure of workpiece and the condition of constant equivalent feed rate. So, the machining state is steady and the cutting force is stabilized. Meanwhile, the feed rate is optimized and the machining quality and efficiency are improved.Three experiments are carried out in this paper, constant cutter radial depth and constant feedrate; constant cutter radial depth and optimized equivalent feedrate; constant cutter engagement arc and constant equivalent feedrate. Experiments results show that the cutting force can be regulated both in equivalent feedrate scheduling method and constant cutter engagement arc and constant equivalent feedrate method. Comparatively, the effective of cutting load regularization is better in constant cutter engagement arc and constant equivalent feedrate. So, the machining method of constant cutter engagement arc and constant equivalent feedrate velocity milling is propitious to the application of the HSM.