An elliptical copper electrode as seen under the microscope.

Despite being developed in the 1940’s, electrical discharge machining continues to mature as a machining technique. And with more and more customers demanding elliptical electrodes, we have developed—in collaboration with our trusted manufacturing partners—a new line of elliptical electrodes. Fully customizable major and minor axes and lengths give you complete freedom in electrode selection.

Elliptical Electrode Characteristics

  • Electrodes are available in lengths from 100mm (4”) to 800mm (32”).
  • Available in brass and copper (standard or oxygen free).
  • Independently customizable major and minor axes.
  • Maximum axis length of 6.0mm (.236”) and minimum length of .6mm (.024”)
  • Perfect for turbine blade cooling holes and stress testing applications.

Elliptical Electrode Applications

Gas Turbine Generators

Due to the extreme temperatures present in gas turbine engines, turbine blades employ film cooling to prevent surrounding air from exceeding their melting point. In film cooling, cool air is pumped through channels in the blades, creating a protective, insulating barrier. To achieve the desired effect, the holes must be able to pump a sufficient volume of air uniformly across the blade surface. An obstacle to sufficient airflow can be cooling holes with insufficient surface area. Though the obvious solution to this problem would be to increase the diameter of cooling holes, sometimes the thinness of the blade precludes this. Elliptical EDM electrodes solve this dilemma, allowing for optimal airflow without compromising the structural integrity of blades.

Stress Testing

Ensuring that materials are robust requires thorough testing. And as cracks can be modeled as elliptical holes with a minor axis of length zero, electrodes with a very high eccentricity can be used for stress testing. Whereas our copper-tungsten plate may be used for simulating large fractures, our elliptical electrodes may be used for simulating smaller stress fractures.

A graph of an ellipse with maximum available eccentricity.

Due to the large variation in major and minor axis combinations, a parts list is unavailable. All elliptical electrodes are made to customer specifications. Please send us your print or initial requirements so that we may manufacture elliptical electrodes to your satisfaction.