Investigation of the shape accuracy of cylindrical holes machined by EDM process

The paper deals with the investigations of influence parameters of electrodischarge machining (EDM) on the shape accuracy of holes machined by EDM process. BP-95. machine with electronic generator type was used to perform EDM process. Kerosene was used as a dielectric. During EDM process the parameters of current were permanent. The shape of electrode and way of passing dielectric were changed. The following parameters were determined: productivity of EDM process and shape accuracy of the drilling holes. The accuracy of bored cylindrical holes, is highest in case of hollowing out with the tubular electrode and for sucking out working liquid by her inner life. In the case of hollowing out with the electrode tubular, sinking the tube with pumping liquid by the inner life is the most favourable method causing the smallest mistakes of outlines of the cylindrically shape. The time of boring the arterial hole is shortest in case of hollowing out with the electrode tubular and for pumping working liquid by inside.