Some considerations on concerning the electrical discharge threading

The electrical discharge machining (EDM) is a machining process based on pulsed electrical discharge effects, which appear between the electrode tool and the workpiece. One may say that the electrical discharge machining is one of the most frequently used nonconventional processes, allowing the obtaining of surfaces which cannot be otherwise achieved through classical machining methods. The electrical discharge machining is also used in order to manufacture hard and extra-hard materials; this process is used to obtain pieces with complex shapes, which would otherwise be difficult or even impossible to obtain, by the use of classical machining methods. The profiled surfaces can be classified according to the final service role. In this respect one may mention threaded, spherical, conical or polygonal surfaces as profiled surfaces. The threaded surfaces could be obtained by classical methods and nonconventional machining methods, among which cutting machining and plastic deformation as classical machining methods are worth mentioning.