Nowadays, wire cut EDM machines are used more and more widely. Do you know their working principle and characteristics?

Principles of wire cut EDM machining

The principle of wire cut EDM machine is to use tools to connect molybdenum wire with the workpiece to insert a pulsed power source. The molybdenum wire is inserted into the pre-drilled small hole on the workpiece, and the wire storage drum moves alternately through the guide wheel. The working piece is installed in the working table and the numerical control device issues instructions according to the processing requirements to control two step-by-step motors to drive the worktable to move in the horizontal X and Y coordinate directions to synthesize an arbitrary curve track, which is then cut into the required shape. During processing, the nozzle sprays the working fluid to the processing area at a certain pressure. When the pulse voltage breaks through the discharge gap between the molybdenum wire and the workpiece, a spark discharge is generated between the two poles to erode the workpiece.

Features of wire cut EDM machining

There is no need to manufacture shaped electrodes and the amount of pre-processing of workpiece materials is small.

Due to the use of longer molybdenum wire for processing in the high speed wire EDM, the loss of molybdenum wire per unit length is less, and the impact on machining accuracy is small.

The molybdenum wire material does not have to be harder than the material itself. It can process materials that is difficult to cut, such as hardened steel and cemented carbide. Non-conductive materials cannot be processed.

Regarding the molybdenum wire is very thin, it can easily process parts with complex shapes, micro-shaped holes, narrow slits, etc., and due to the narrow slit, the amount of parts removed is small, the material loss is small, and valuable materials can be saved and the cost is low.

Since the molybdenum wire does not directly contact the workpiece during processing, the workpiece is almost free from cutting force, which is suitable for processing low-rigidity workpieces and small parts.

Direct use of electrical and thermal energy processing can easily adjust the parameters that affect the processing accuracy (pulse width, interval, current, etc.). It is conducive to the improvement of processing accuracy, convenient operation and short processing cycle. It is convenient to realize the automation in the processing process.