面向数控机床运行状态的切削稳定性预测研究
|
摘要
切削加工过程中出现的颤振失稳现象,是限制机床加工质量和加工效率的主要因素。传统切削稳定性预测模型大多基于机床静止状态下的动力学特性,并采用恒定的切削力系数表征不同的切削条件。但在加工过程中,系统动力学特性和切削力系数会随着主轴转速等影响因素而变化,导致预测的切削稳定性叶瓣图在实际工程运用中出现偏差。针对机床运行状态下切削稳定性的准确预测问题,提出一种切削稳定性叶瓣图修正方法。该方法以刀具系统动力学特性与切削力系数为研究对象,首先建立主轴转速样本信息,将考虑转速效应的主轴轴承运行刚度写入机床有限元模型中,获取刀尖频率响应函数及其对应的各阶模态参数,以此结合模态拟合法和插值算法重构任意转速下的刀尖频响函数,同时以各切削参数为变量构建切削力系数响应面预测模型,进而将与转速对应的刀尖频率响应函数和不同切削条件下的切削力系数作为传统切削稳定性预测模型的输入,并通过结合自适应粒子群算法共同求解各转速下的极限切削深度,从而在全转速范围内绘制切削稳定性叶瓣图。将该方法应用于1台3轴立式加工中心的实际工序中,采用多组预测的无颤振切削参数进行切削实验,并通过切削力信号的频谱分析判定切削过程中未出现颤振,验证了稳定性叶瓣图修正方法的有效性,为无颤振切削参数的合理选择奠定了技术支持。
Chatter in machining process is the main factor limiting the machining quality and machining efficiency. The traditional machining stability prediction models are mostly based on the machine tool dynamics under stationary state, and use the constant cutting force coefficients to represent different cutting conditions. However, in real machining process, system dynamics and the cutting force coefficients will change caused by the factors such as the spindle speed, leading inaccurate chatter prediction. Thus, a method to modify the conventional machining stability lobe diagram(SLD) is proposed to ensure the prediction accuracy based on the relationships among cutting parameters, system dynamics and cutting force coefficients. In this method, the sample information of the spindle speed is initially set up, and then the speed-dependent bearing stiffness is applied into the whole machine tool finite element model(FEM). Then the tool tip frequency response functions(FRFs) are obtained and their related modal parameters are identified. Therefore, with these sample modal parameters, the tool tip FRFs at any speed can be reorganized based on the modal fitting technique and the interpolation algorithm.A response surface method is established for predicting the cutting force coefficients under different machining conditions, which are further combined with the speed-dependent tool tip FRFs to be the inputs of the machining stability mathematical model. This model is combined with the adaptive particle swarm optimization algorithm to achieve the limiting cutting depth at any spindle speed. Then a modified SLD in full spindle speed range is plotted. The proposed method is applied to a three-axis vertical machining center, and different sets of the predicted no chatter cutting parameters are adopted to carry out the chatter tests. And the frequency spectrums of the cutting force signals are analyzed to indicate that no chatter occurred, which verify the feasibility of the proposed method and show that it can lay a foundation for the cutting parameters selection.
Chatter in machining process is the main factor limiting the machining quality and machining efficiency. The traditional machining stability prediction models are mostly based on the machine tool dynamics under stationary state, and use the constant cutting force coefficients to represent different cutting conditions. However, in real machining process, system dynamics and the cutting force coefficients will change caused by the factors such as the spindle speed, leading inaccurate chatter prediction. Thus, a method to modify the conventional machining stability lobe diagram(SLD) is proposed to ensure the prediction accuracy based on the relationships among cutting parameters, system dynamics and cutting force coefficients. In this method, the sample information of the spindle speed is initially set up, and then the speed-dependent bearing stiffness is applied into the whole machine tool finite element model(FEM). Then the tool tip frequency response functions(FRFs) are obtained and their related modal parameters are identified. Therefore, with these sample modal parameters, the tool tip FRFs at any speed can be reorganized based on the modal fitting technique and the interpolation algorithm.A response surface method is established for predicting the cutting force coefficients under different machining conditions, which are further combined with the speed-dependent tool tip FRFs to be the inputs of the machining stability mathematical model. This model is combined with the adaptive particle swarm optimization algorithm to achieve the limiting cutting depth at any spindle speed. Then a modified SLD in full spindle speed range is plotted. The proposed method is applied to a three-axis vertical machining center, and different sets of the predicted no chatter cutting parameters are adopted to carry out the chatter tests. And the frequency spectrums of the cutting force signals are analyzed to indicate that no chatter occurred, which verify the feasibility of the proposed method and show that it can lay a foundation for the cutting parameters selection.
引文
[1]Liang Ruijun,Ye Wenhua,Huang Xiang.Three-dimensional stability predication for milling process[J].Journal of Sichuan University(Engineering Science Edition),2011,43(3):219-224.[梁睿君,叶文华,黄翔.铣削加工3维稳定性预测[J].四川大学学报(工程科学版),2011,43(3):219-224.]
[2]Chi Yulun,Li Haolin.Determination of chatter stability field lobe diagrams for a milling processing[J].Journal of Vibration and Shock,2014,33(4):90-93.[迟玉伦,李郝林.铣削颤振稳定域叶瓣图确定方法研究[J].振动与冲击,2014,33(4):90-93.]
[3]Wang Bo,Sun Wei,Wen Bangchun.Stability prediction and influence factors analysis of high-speed spindle system[J].Journal of Mechanical Engineering,2013,49(21):18-24.[汪博,孙伟,闻邦椿.高速主轴系统切削稳定性预测及影响因素分析[J].机械工程学报,2013,49(21):18-24.]
[4]Cao Hongrui,Chen Xuefeng,He Zhengjia.Modeling of spindle-process interaction and cutting parameters optimization in high-speed milling[J].Journal of Mechanical Engineering,2013,49(5):161-166.[曹宏瑞,陈雪峰,何正嘉.主轴-切削交互过程建模与高速铣削参数优化[J].机械工程学报,2013,49(5):161-166.]
[5]Liu Yu,Wang Zhenyu,Liu Kuo,et al.Chatter stability prediction in milling using time-varying uncertainties[J].International Journal of Advanced Manufacturing Technology,2016,89(9):2627-2636.
[6]Long Xinhuan,Meng Dehao,Chai Yingang.Effects of spindle speed-dependent dynamic characteristics of ball bearing and multi-modes on the stability of milling processes[J].Meccanica,2015,50(12):3119-3132.
[7]?z?ahin O,Budak E,?zgüven H N.In-process tool point FRF identification under operational conditions using inverse stability solution[J].International Journal of Machine Tools&Manufacture,2014,89:64-73.
[8]Grossi N,Sallese L,Scippa A,et al.Chatter stability prediction in milling using speed-varying cutting force coefficients[J].Procedia Cirp,2014,14:170-175.
[9]Tian Fengjie,Qi Genxiang.Study of cutting force coefficients identification aiming at milling process of die steel NAK80[J].Tool Engineering,2015(2):12-15.[田凤杰,齐根想.NAK80模具钢铣削加工过程中切削力系数识别[J].工具技术,2015(2):12-15.]
[10]Deng Congying,Yin Guofu,Fang Hui,et al.Optimal configuration of dynamic stiffness of machine tool joints based on orthogonal experiment[J].Journal of Mechanical Engineering,2015,51(19):146-153.[邓聪颖,殷国富,方辉,等.基于正交试验的机床结合部动刚度优化配置[J].机械工程学报,2015,51(19):146-153.]
[11]Yin Didi,Gao Naiyun,Gao Menghong,et al.Optimization of pre-treatment of Taihu Lake water with response surface methodology[J].Journal of Sichuan University(Engineering Science Edition),2015,47(1):192-199.[殷娣娣,高乃云,高梦鸿,等.响应面分析法优化太湖原水作为水厂水源的预处理工艺[J].四川大学学报(工程科学版),2015,47(1):192-199.]
[12]Deng Congying,Liu Yun,Yin Guofu,et al.Research on machine tool spatial dynamic characteristics based on response surface method[J].Advanced Engineering Sciences,2017,49(4):211-218.[邓聪颖,刘蕴,殷国富,等.基于响应面方法的数控机床空间动态特性研究[J].工程科学与技术,2017,49(4):211-218.]
[13]Hu Teng,Yin Guofu,Sun Mingnan.Dynamic performance of a shaft-bearing system with centrifugal force and gyroscopic moment effects[J].Journal of Vibration and Shock,2014,33(8):100-108.[胡腾,殷国富,孙明楠.基于离心力和陀螺力矩效应的“主轴-轴承”系统动力学特性研究[J].振动与冲击,2014,33(8):100-108.]
[14]Guan Yueqi,Wei Kexiang,Zhang Wenming,et al.Stability analysis and experimental research for three-dimensional dither in processing of high speed milling[J].Journal of Vibration and Shock,2017,36(4):192-197.[关跃奇,魏克湘,张文明,等.高速车铣加工三维颤振的稳定性分析与试验研究[J].振动与冲击,2017,36(4):192-197.]
[2]Chi Yulun,Li Haolin.Determination of chatter stability field lobe diagrams for a milling processing[J].Journal of Vibration and Shock,2014,33(4):90-93.[迟玉伦,李郝林.铣削颤振稳定域叶瓣图确定方法研究[J].振动与冲击,2014,33(4):90-93.]
[3]Wang Bo,Sun Wei,Wen Bangchun.Stability prediction and influence factors analysis of high-speed spindle system[J].Journal of Mechanical Engineering,2013,49(21):18-24.[汪博,孙伟,闻邦椿.高速主轴系统切削稳定性预测及影响因素分析[J].机械工程学报,2013,49(21):18-24.]
[4]Cao Hongrui,Chen Xuefeng,He Zhengjia.Modeling of spindle-process interaction and cutting parameters optimization in high-speed milling[J].Journal of Mechanical Engineering,2013,49(5):161-166.[曹宏瑞,陈雪峰,何正嘉.主轴-切削交互过程建模与高速铣削参数优化[J].机械工程学报,2013,49(5):161-166.]
[5]Liu Yu,Wang Zhenyu,Liu Kuo,et al.Chatter stability prediction in milling using time-varying uncertainties[J].International Journal of Advanced Manufacturing Technology,2016,89(9):2627-2636.
[6]Long Xinhuan,Meng Dehao,Chai Yingang.Effects of spindle speed-dependent dynamic characteristics of ball bearing and multi-modes on the stability of milling processes[J].Meccanica,2015,50(12):3119-3132.
[7]?z?ahin O,Budak E,?zgüven H N.In-process tool point FRF identification under operational conditions using inverse stability solution[J].International Journal of Machine Tools&Manufacture,2014,89:64-73.
[8]Grossi N,Sallese L,Scippa A,et al.Chatter stability prediction in milling using speed-varying cutting force coefficients[J].Procedia Cirp,2014,14:170-175.
[9]Tian Fengjie,Qi Genxiang.Study of cutting force coefficients identification aiming at milling process of die steel NAK80[J].Tool Engineering,2015(2):12-15.[田凤杰,齐根想.NAK80模具钢铣削加工过程中切削力系数识别[J].工具技术,2015(2):12-15.]
[10]Deng Congying,Yin Guofu,Fang Hui,et al.Optimal configuration of dynamic stiffness of machine tool joints based on orthogonal experiment[J].Journal of Mechanical Engineering,2015,51(19):146-153.[邓聪颖,殷国富,方辉,等.基于正交试验的机床结合部动刚度优化配置[J].机械工程学报,2015,51(19):146-153.]
[11]Yin Didi,Gao Naiyun,Gao Menghong,et al.Optimization of pre-treatment of Taihu Lake water with response surface methodology[J].Journal of Sichuan University(Engineering Science Edition),2015,47(1):192-199.[殷娣娣,高乃云,高梦鸿,等.响应面分析法优化太湖原水作为水厂水源的预处理工艺[J].四川大学学报(工程科学版),2015,47(1):192-199.]
[12]Deng Congying,Liu Yun,Yin Guofu,et al.Research on machine tool spatial dynamic characteristics based on response surface method[J].Advanced Engineering Sciences,2017,49(4):211-218.[邓聪颖,刘蕴,殷国富,等.基于响应面方法的数控机床空间动态特性研究[J].工程科学与技术,2017,49(4):211-218.]
[13]Hu Teng,Yin Guofu,Sun Mingnan.Dynamic performance of a shaft-bearing system with centrifugal force and gyroscopic moment effects[J].Journal of Vibration and Shock,2014,33(8):100-108.[胡腾,殷国富,孙明楠.基于离心力和陀螺力矩效应的“主轴-轴承”系统动力学特性研究[J].振动与冲击,2014,33(8):100-108.]
[14]Guan Yueqi,Wei Kexiang,Zhang Wenming,et al.Stability analysis and experimental research for three-dimensional dither in processing of high speed milling[J].Journal of Vibration and Shock,2017,36(4):192-197.[关跃奇,魏克湘,张文明,等.高速车铣加工三维颤振的稳定性分析与试验研究[J].振动与冲击,2017,36(4):192-197.]
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |