High Performance Measuring and Micro Electrical Discharge Machining (HPMEDM)

Project start: 01.09.2013

Project end: 01.05.2016

Funding: CTI

Further partners: SARIX SA - Switzerland

Abstract: The project, carried out by SUPSI and Sarix SA, consisted in designing and realizing the prototype of a new generation of EDM machines for drilling gas turbine blades. The new machine integrates a 3D laser scanner that, before each working cycle, allows to know the actual shape of the blade and its position on the workpiece table of the machine to position the electrode on the work surface with an accuracy of 10 μm.

This achievement needed also an overall review of the machine design and in particular of the electronic boards for generator control, for CNC control and for data communication.

The first prototype of the new machine is already in use in the production environment within SARIX SA. The performance of the components developed within the project have the following characteristics:

  • Reaction time from 2ms to 500μs.
  • Feedback without dead times (<50 μs)
  • Axis precision from ±1 μm to ±0.1 μm
  • Machining of smaller holes (80 μm).
  • Faster beginning of drilling from 6 to 2-3 seconds
  • Detection of workpiece position with a probing error of: ±10μm

The ability to machine the blades with this accuracy opens the field for new design solutions of the cooling channels and then for the objective, stated by the major manufacturers, of developing of the most advanced 1,700°C-class turbine technology.