Design of Impressed Current Cathodic Protection (ICCP) Systems for U.S. Navy Hulls

摘要

The goal of impressed current cathodic protection (ICCP) design for ship hulls, under the Navy Ship's Technical Manual (NSTM, Chapter 633), is to provide a uniform potential distribution at -0.85 V, +- 0.05 V, versus a silver/silver chloride (Ag/AgCl) reference cell, over the wetted hull surface during all operational aspects of an active ship. To accomplish this, the physical scale modeling (PSM) technique, combined with a rigid design protocol, has been used extensively by the U. S. Navy to provide optimal and retrofit upgrade designs of ICCP systems for huls. The ICCP design guidance, provided by the protocol, defines the hull properties, hull damage and general power supply requirements. PSM is utilized to determine optimal placement of ICCP components (anodes and reference cells) and to evaluate performance for up to a 15percent wetted hull coatings loss under static (pierside) and dynamic (underway) conditions. Data are provided which illustrate the use of the design protocol criteria, along with the integrated PSM technique, to determine ICCP system design and evaluate performance.