微细倒锥孔在线加工参数调控的电火花加工工艺

基于微细孔电火花加工中观测到的“腰鼓”现象,进行了微细倒锥孔的在线加工参数调控电火花加工工艺的研究.实验研究了开路电压、进给深度、变压深度、放电电容等加工参数对微孔加工孔形的影响.通过对工艺参数的优化选择,加工得到出入口直径平均相差18.6 μm、锥度为1.16°的倒锥孔,可用于柴油发动机倒锥喷孔的加工.进一步实验了工...

EDM Drilling Process of Micro Tapered Holes by Online Control of Machining Parameters

Based on the ＂waist drum＂ phenomenon observed in micro holes＇ EDM drilling, an EDM drilling process of micro tapered holes was presented by using online control of electric parame-ters. The effects to micro hole＇s shape of open circuit voltage, electrode feeding depth, voltage chang-ing depth and terminal capacitance were investigated experimentally. By optimizing the parameters, micro tapered holes whose average diameter difference of inlet and outlet 18.6 μm and average taper angle 1.16 degrees were obtained, which might satisfy the machining requirement of the tapered holes on diesel injector nozzles. A further method that coats the back side of workpiece with paraffin wax was tried and to make the machining debris reside around outlet. Thus lager taper angle, over 25 μm difference of inlet and outlet of the holes can be obtained.