Electrical Discharge Machining (EDM) Process Description
Electrical Discharge Machining (EDM)Electrical Discharge Machining is considered one of the most accurate manufacturing processes available for creating complex or simple shapes and geometries within parts and assemblies. EDM works by eroding the material in the path of electrical discharges that form an arc between an electrode tool and the work piece itself. Electrical Discharge Machining manufacturing is affordable and a desirable manufacturing process when low unit volume or high accuracy is required.
EDM system consists of a shaped tool or wire electrode, and the part. The part is connected to a power supply. Sometimes to create a potential difference between the work piece and tool, the work piece is immersed in a dielectric (electrically nonconducting) fluid, which is circulated to remove debris.
The cutting pattern is usually CNC controlled. Many Electrical Discharge Machine electrodes can rotate about multiple axes allowing for cutting of internal cavities. This makes EDM a highly capable manufacturing process.
EDM comes in two basic types: wire and probe (diesinker). Wire Electrical Discharge Machining is used primarily for shape cut through a selected part or assembly. With a wire EDM machine, if a cut out needs to be created, an initial hole must first be drilled in the material, and then the wire can be fed through the hole to complete the machining. Sinker (diesinking) EDMs are generally used for complex geometries where the EDM machine uses machined graphite or copper electrode to erode the desired shape into the part or assembly. Sinker EDM can cut a hole in the part without having the hole pre-drilled for the electrode.
Used Electrical Discharge Machinery is classified as E2400, E2425, and E2475 for conventional ram type, sinker, N/C and CNC (Conventional) and wire type respectively. Charmilles, Acer, Belmont, Chevalier, Easco, Fanuc, Makino, Mitsubishi, Omega, EDM Solutions Columbia, Samstar, Sodick and Agie manufacture EDMs.