Vibration amplitude characteristics of tubular electrode in EDM drilling
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摘要: 在采用管状电极高压冲液的电火花穿孔加工中,较大幅值的电极随机振动将导致加工中侧壁短路和二次放电,这对穿孔加工精度和效率造成不利影响。本文以高压冲液管状电极为研究对象,采用仿真、实验验证及对比分析的方法研究了电极微观振动幅值特性。基于ANSYS有限元软件平台,建立了描述电极振动特性的有限元模型,通过数值模拟分析了冲液压力、导向器间隙、穿孔深度、放电间隙、主轴转速、电极悬长多因素对电极振动幅值的影响,分析了多因素耦合情况下各因素对电极振动幅值的影响程度,并进一步进行了实验验证。研究表明导向器间隙、穿孔深度、冲液压力与电极振动幅值成正相关性,减小导向器间隙由10 μm至1 μm,可有效降低孔径误差20 μm。多因素耦合分析得到电极振动幅值影响因素主次顺序为:穿孔深度、冲液压力、放电间隙、主轴转速、电极悬长。此项研究为优化电火花穿孔加工工艺与主轴设计提供依据。
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关键词:
- 电火花加工(EDM) /
- 穿孔成形 /
- 管状电极 /
- 振动特性 /
- 流固耦合
Abstract: In the drilling of electric discharge machining (EDM) by use of a tubular electrode with high-pressure dielectric fluid, the random electrode vibration causes short circuit and second discharge which have a bad effect on machining accuracy and efficiency. In this paper, the microscopic amplitude characteristics of the electrode vibration are researched by adopting methods of simulations, experiments and comparative analysis. Based on ANSYS simulation platform of finite-element software, a finite element model was established to simulate the vibration characteristics of the tubular electrode, and then the effects of multiple factors including hydraulic pressure of dielectric fluid, electrode-guide gap, drilling depth, discharge gap, spindle speed and electrode overhanging length on the electrode vibration amplitude were analyzed. In addition, the significant level of every factor was analyzed by numerical simulation under the condition of coupling these factors. The EDM drilling experiments were carried out to verify the simulation results. Our research shows that the guide gap, drilling depth and hydraulic pressure have positive correlation with the electrode vibration amplitude, and reducing the guide gap from 10 μm to 1 μm can effectively reduce 20 μm of the error of the aperture. By analyzing these coupling factors, the order of significance affecting the electrode vibration is drilling depth, hydraulic pressure of dielectric fluid, discharge gap, spindle speed and electrode overhanging length. This research provides a basis for optimizing machining process and spindle design of EDM drilling using a tubular electrode. -
[1] 叶树林,刘晋春.高速电火花小孔加工机理的研究[J].电加工,1997(4):15-18.YE S L,LIU J C.The research on machining mechanism of high speed small hole EDM drilling[J].Electromachining & Mould,1997(4):15-18(in Chinese). [2] 王志强,佟浩,李勇,等.气膜冷却孔电火花加工用复合功能主轴[J].清华大学学报(自然科学版),2014,54(9):1131-1137.WANG Z Q,TONG H,LI Y,et al.Multifunctional spindle for machining film cooling holes in EDM[J].Journal of Tsinghua University (Science and Technology),2014,54(9):1131-1137(in Chinese). [3] 刘正勋,陈祥康.深小孔的高速电火花加工工艺[J].机械科学与技术,1989 (5):5-8.LIU Z X,CHEN X K.The machining technology of EDM on deep hole[J].Mechanical Science and Technology,1989(5):5-8(in Chinese). [4] YILMAZ O,OKKA M A.Effect of single and multi-channel electrodes application on EDM fast hole drilling performance[J].The International Journal of Advanced Manufacturing Technology,2010,51(1-4):185-194. [5] PHAM D T,IVANOV A,BIGOT S,et al.An investigation of tube and rod electrode wear in micro EDM drilling[J].The International Journal of Advanced Manufacturing Technology,2007,33(1-2):103-109. [6] 郭维城,郭永丰,侯朋举,等.电火花加工阵列穿丝孔的试验研究[J].机械设计与制造,2013 (2):226-228.GUO W C,GUO Y F,HOU P J,et al.Study on the array wire threading hole test in electrical-discharge process[J].Machinery Design and Manufacture,2013(2):226-228(in Chinese). [7] 贾振元,郑新毅,王福吉,等.微孔电火花加工极间工作液流动状态研究[J].大连理工大学学报,2010,50(2):188-193.JIA Z Y,ZHEN X Y,WANG F J,et al.Research on flow state of interelectrode working fluid in micro-EDN[J].Journal of Dalian University of Technology,2010,50(2):188-193(in Chinese). [8] 张淑奎,王燕青,黄河,等.旋转电极内冲液电火花铣削加工流场仿真及实验研究[J].电加工与模具,2011(1):1-5.ZHANG S K,WANG Y Q,HUANG H,et al.Research on rotation electrode and iner jetted dielectric EDM milling flow simulation and experiment[J].Electromachining & Mould,2011(1):1-5(in Chinese). [9] 唐家鹏.Fluent14.0超级学习手册[M].北京:北京人民邮电出版社,2013:30-38.TANG J P.The study guide of Fluent14.0[M].Beijing:Posts & Telecom Press,2013:30-38(in Chinese). [10] 黄志新.ANSYS Workbench 14.0超级学习手册[M].北京:人民邮电出版社,2013:505-520.HUANG Z X,The study guide of ANSYS Workbench 14.0[M].Beijing:Posts & Telecom Press,2013:505-520(in Chinese). [11] 茆诗松.实验设计[M].2版.北京:中国统计出版社,2012:111-123.MAO S S.Design of experiments[M].2nd ed.Beijing:China Statistics Press,2012:111-123(in Chinese). [12] 何为.优化实验设计方法及数据分析[M].北京:化学工业出版社,2012:29-57.HE W.Optimization design of experiment method and data analysis[M].Beijing:Chemical Industry Press,2012:29-57(in Chinese).
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