Feed rate control of the wire-EDM process
Wire electrical discharge machining (wire-EDM) is a process of metal cutting where a special traveling wire is used as the cutting tools and metal cutting is achieved through spark erosion. Since the introduction of CNC wire-EDM, the technology of monitoring and control of machining process has been accelerated because of the need for improvement in machining efficiency, wire breakage prevention and part quality. In order to guarantee the high accuracy of the machining process, the spark erosion should occur with an as constant as possible gap width. Only in the optimum state, the highest material removal rate can be realized. The quality of feed rate control determines the stability of the gap width the machining process. Based on the characteristics of gap voltage waveform, there are four major gap states classified as open circuit, normal spark, arc discharge and short circuit. To achieve the stability of the machining operation, a control strategy is proposed to optimize of the feed rate. The optimization of the feed rate control is an important factor for maintaining the process stability while spark erosion machining. The parameters of the feed rate control are a part of process analysis and must satisfy the goals of feed rate control. In the presented paper, relevant process parameters are investigated and assessed. The following four process variables can be used for feed control: gap voltage, ignition delay time, voltage breakdown, high-frequency parts of the burning voltage. A new pulse discriminating and control system has been developed for process monitoring and control in wire-EDM. In this paper, a wire-EDM pulse discriminating and control system is developed for the identification of gap states, then use these relevant process parameters to control machine process and make the process stability. The developed pulse discriminating and control system can significantly reduce the arc discharge and short sparking frequency as well as achieve stable machining under the condition where the instability of machining operation is prone to occur.
wire-EDM process control feed rate
Wang Zhiyong Jia Zhixin Dong Shaohua
University of Science and Technology Beijing Beijing,China
国际会议
北京
英文
2007-08-05（万方平台首次上网日期，不代表论文的发表时间）