Brief history of electric arc erosion

18th Century:

The English researcher Joseph Priestley carrys out electrical experiments and recognizes the erosive effect of electric discharge.

About 1940:

The Russian physicists Lazarenko describe the removal of material by means of electric arcs, which are produced through the vibration of an electrode. Therewith the basis for electric arc erosion is provided.

In the following period:

One recognices that this technique is not suitable for exact machining and is developing the EDM, electrical discharge machining. Arc erosion on the other hand is used where quick removal and less accuracy is required. Therefore this method of application up to now is in use mainly to erode out broken-off tools. Problems:
An electric arc can only be formed when the electrode is freely vibrating. With jerky or too fast feed of the electrode on the other hand, the vibration is affected and a short-ciruit current is created. Similarly, if the electrode has lateral contact with the workpiece, e.g. because of cuttings. To prevent an overload of the equipment in this case they use transformers with very soft operation behaviour. A short-circuit current is not prevented by that, but limited. Since short-circuits often occur at the electric arc eroding, transformer and rectifier however will be heavily loaded, the devices will soon get hot and then turn off. Beyond that the soft operation behaviour complicates the handling.


Kullick-Gerätebau puts Eroding Equipment LE on the market. Therewith the problem of the short-circuits is resolved as the eroding current is controlled, in the case of a short circuit is shut down completely and automatically turned on again (Kullick-EEC-control). And this enables the use of fixed-voltage-transformers for stable, constant eroding currents. Advantages:

- Clear eroding signals to the operator. The devices are therefore also applicable well in CNC-machines.
- Quick and easy eroding because of the stable eroding voltages.
- Significantly increased operating time and efficiency of the devices.
- Reduced load of transformer and rectifier.

Since that time Kullick Eroding Equipment LE devices are worldwide in use, if broken tools must be removed reliably and quickly.
The easy handling allows eroding without any special knowledge.

Erodiergeräte Serienproduktion    Erodierkopf Serienproduktion

Kullick Eroding Equipment LE
Development and production: Made in Germany