A self-flushing method with spark-erosion machining

It is one of the problems in EDM that in some cases it is difficult to avoid arcing, especially in machining where no flushing holes can be made in the electrode. In those cases a periodically lifting of the electrode is usually applied. However, since the lifting action does not make an effective use of the flow of the dielectric fluid, this way of machining can strongly decrease the average metal removal rate. This paper describes the introduction of an pumping action of the dielectric fluid by means of a special electrode movement. With this way of machining no additional flushing is necessary. A prototype of this self-flushing system is developed and tested on its effectiveness.