Fixed electrode for electro-chemical machining - has outer surface of electrode covered with insulation material and mounted in sleeve to shield surrounding material

摘要

The elongated hole is made e.g. inside a bush welded on a cylinder to make a connection to a ring channel, cut in the cylinder bore of a pneumatic valve housing. An edge between the ring channel and the cylinder bore is a control edge and should not be damaged when the bore is made. The fixed electrode with which the hole is made, is in the shape of a hollow cylinder with flattened sides. The flat sides give return channels for the electrolyte. The outer surface of the electrolyte is covered with insulation material. A saw slot is made in the bottom of the insulation, through which flat streams of electrolyte flow. The side faces of the electrode which are exposed through the saw slots are the working surfaces of the electrode.