Process for electrochemical machining

摘要

An electrolyte is circulated between the surface to be machined, raised to an anode potential, and a tool electrode (9') raised to a cathode potential. The electrolyte contains lithium nitrate as a unique active product with a concentration of between 20 g/l and 2350 g/l and preferably between 50 g/l and 250 g/l. The process can be applied to the machining of the surface of any metallic component and in particular to the machining of the internal surface of tubular components (5) such as penetrations in the vessel bottom or closure head of a nuclear reactor; in this case the electrochemical machining cell consists of a cylindrical tool electrode (9') placed inside the component to be machined.