the cathodic protection system of the inner surface of a steel pipe

摘要

The corrosion-prevention system comprises a metallic conduit having an exterior surface subjected to the corrosive effects of a surrounding ambient wetted environment, and an interior surface subjected to the corrosive effects of fluids conveyed within the conduit. First cathodic protection means completes a first electrolytic path with the corrosively-wetted environment serving as the electrolyte, thereby cathodically protecting the exterior surface. Second cathodic protection means protects the interior surface and includes a plurality of inert anodes electrically connected to cathodic plate means which are located exteriorly of the conduit so as to intercept the flow of current in said first electrolytic path and conduct the current to the inert anodes and complete a second electrolytic path through the corrosive fluids conveyed within said conduit.