Brush discharge plastics. The ability of an electrical discharge to cause an explosion in flammable atmospheres is measured by the "effective energy" of the discharge. The effective energy of brush discharges is 10-20 mJ, much larger than that of corona discharges 0.1 mJ. Therefore, brush discharges are considered an explosion hazard, while corona discharges are not. Brush discharges can occur from charged insulating plastics (for example polythene) to a conductor. Brush discharge A brush discharge is an electrical disruptive discharge similar to a corona discharge that takes place at an electrode with a high voltage applied to it, embedded in a nonconducting
Electrical discharge machining Electrical discharge machining Electrical discharge machining (EDM), also known as spark machining, spark eroding, burning, die sinking, wire burning or wire erosion, is a manufacturing process whereby a desired shape is obtained by using electrical discharges (sparks). Material is removed from the work piece by a series of rapidly recurring current discharges between two electrodes, separated by a dielectric liquid and subject to an electric voltage. One of the electrodes is called the tool-electrode, or simply the "tool" or "electrode," while the other is called the workpiece-electrode, or "work piece." The process depends upon the tool and work piece not