Method for creating bore by eroding in double walled area located at blade of turbine, using insert of conductive plastic for avoidance of damage

摘要

When creating a bore into a blade of a turbine in a double walled area the electrodes are frequently guided through the upper layer during the process and hit the lower layer with unrestricted forces, causing damage to the blade and to the electrode. A sacrificing insert (3) made of a conductive synthetic material or an alloy with a low melting point is positioned between both layers, absorbing some of the forces applied by the electrodes.