What is EDM?


EDM stands for electrical discharge machining, the applications best suited for this metal removal process are those characterized by extremely exacting tolerances and situations that would be extremely difficult or impossible to handle with any other method of machining.


Growth of EDM


EDM has rapidly earned its place alongside milling and grinding equipment as a proactive, mainstream technology. EDM is best known for its ability to machine complex shapes in very hard metals. The most common use of EDM is machining dies, tools and molds made of hardened steel, tungsten carbide, high-speed steel and other workpiece materials that are difficult to machine by “traditional” methods.


The process has also solved a number of problems related to the machining of “exotic” materials such as Hastelloy, Nitralloy, Waspaloy and Nimonic, which are used on a large scale in the aeronautical and aerospace industries.


With the reduction in electrode wear and increased sophistication of EDM controls in rams, new EDM processes use simple-shaped electrodes to 3D mill complex shapes. EDM also is being used for polishing small, intricate surfaces.


Since EDM does not involve workpiece/tool forces like a mill or grinder, it is possible to EDM shapes that would break conventional cutting tools or be broken by them.


Different Types of EDM


  1. RAM EDM

RAM EDM, also known as plunge EDM or standard EDM, is the oldest form of EDM machining. It generally consists of an electrode usually made out of graphite that is plunged into a workpiece in order to create a blind-shaped cavity. It can also be used to generate through holes and geometry but these are not the primary uses of the process.


  1. Drill EDM

Drill EDM uses rotating concentric electrodes to drill through a workpiece and basically performs the same functions as a drill press, except that the material hardness is not a factor and the accuracy of the finished hole is far superior than what any drill press can produce. It is best used to drill start holes for the wire EDM in already hardened material as well as accurate very small holes for industries like aerospace and medical equipment.


  1. Wire EDM

Wire EDM uses a traveling wire electrode (usually .010” diameter or smaller) that goes through the workpiece. The wire, in this case, is controlled by computer following the assigned geometry for the part to be produced.


EDM for Tooling Applications


When a part requires special / unique conventional cutting tools, electrodes are easy to machine, unlike carbide. Equally important, the wire used by a wire EDM is available as a standard, off-the-shelf component. EDM is a low cost tooling option when you need short run stamping (less than 5,000 pieces) and low volume broaching. With EDM, there’s no need to make a die set. That’s why EDM is used to make sewing machine components and prototypes. Instead of using expensive broaches, EDM is a very attractive form of low-cost tooling. This is a reason companies use EDM to produce splines and gear teeth along with all their metal stamping & mold making needs.


Where to Find The Reliable EDM Machines Manufacturer?


About this question, I recommend that you can try to visit the website of OCEAN Technologies Co., Ltd.. This company is specializing in kinds of high quality EDM machines. If you need more information about CNC drilling EDM machines, please do not hesitate to check out OCEAN product pages and feel free to send inquiry to them.


Article Source: Mercatech, Inc.