Abstract: Based on the cylindrical surface parametric equation,an arbitrary space plane coordinate system and the parametric equations for any cylindrical surface and provide a composite spiral path feed processing methods.After the experimental study,the use of EDM electrodes circular helix trajectory and the bottom side got the same space as cylindrical surface roughness.Shorten the processing time and improve processing accuracy,the EDM space cylindrical surface provides an effective method.

Key words: cylindrical hole, helix, interpolation algorithm, discharge parameter, Electric Discharge Machining(EDM)