Unique couple inhibits galvanic corrosion of dissimilar metal pipes

摘要

In piping systems that carry seawater, particularly shipboard cooling-water piping systems, dissimilar-metal couples are frequently found and these interfaces can cause serious galvanic corrosion of the more active metal in the couple. The corrosion results from oxidation that occurs at the more active metal when the active and noble metals are in electrical contact with an electrolyte (seawater) and electrically connected together through an external circuit. To address this problem, NACE International member John Beavers, FNAGE, chief scientist at DNV Columbus, Inc. (Dublin, Ohio), patented a galvanic corrosion inhibiting coupling (GCIC) device that mitigates galvanic corrosion found in dissimilar-metal piping systems in seawater applications. More recently, Beavers, along with NAGE member Brett Tossey, senior engineer at DNV, added an automatic control system to the GCIC, and both were recently awarded a second U.S. patent for this improvement.