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25 NACE INTERNATIONAL: VOL. 55, NO. 10 MATERIALS PERFORMANCE OCTOBER 2016 FIGURE 4 Pile-to-seawater potentials. l ation , th e own er 's safety re vie w determined this option would be sig- nificantly safer to install than the alternative galvanic anode system. Installation and Commissioning The detailed design called for installing six anode sleds at nominal locations 25 m from the sheet pile wall and spaced 34 m apart. Three oil-cooled transformer rectifi- ers would provide the direct current power to the anodes, with each rectifier powering a pair of anode sleds as shown in the con- ceptual drawing (Figure 1). Installation of the ICCP system took less than a week to complete. Each of the sleds was installed using a land-based crane (Figure 2). The cabling was routed along the sea f loor and secured in place with concrete weights installed by a diver. The cabling was routed up to the rectifiers (Figure 3) by the site electrician. Once the system had been installed and al l of th e cabling was c onn ect ed , secured , and inspected , the system was energized and commissioned . The first step in the commissioning process was to record native potentials along the length of the jetty to provide the baseline potentials prior to applying the CP current. All mea- surements were made with respect to a Ag/AgCl reference electrode using a cali- brated multimeter. For potential measure- ments, nine test locations were identified just below the seawater surface (on the top of the submerged portion of the piles) and near the sea bed . These locations were u s e d t h r o u g h o u t t h e c o m m i s s i o n i n g process. Although the piles were coated , the overall coating condition was unknown and future deterioration was anticipated during the 30-year design life. The initial protective current requirement was con- siderably less than the design capacity, and that is expected to extend the life of the sys- tem. Once the system was energized, the anode outputs were measured to confirm the proper operation of each of the six anode sleds. The system was polarized within 72 h, and the total system current was reduced to ~350 A. Instant-off poten- tials confirmed that the system was provid- ing suf ficient polarization to meet the appropri at e d esign crit eri a p er NAC E SP0176-2007 1 and DNV-RP-B401 2 for steel piles in seawater (Figure 4). The length of time from the start of the installation to the completion of the commissioning and test- ing was a total of two weeks. Summary The use of impressed current anode sleds proved to be a cost-effective alterna- tive to galvanic anodes for this marine jetty project. The impressed current system pro- vided a much longer anode life, greatly reduced installation time, and facilitated a safer installation process—all at a signifi- cantly reduced initial investment cost. References 1 NACE SP0176-2007, "Corrosion Control of Submerged Areas of Permanently Installed Steel Offshore Structures Associated with Petroleum Production" (Houston, TX: NACE International, 2007). 2 DNV-RP-B401, "Cathodic Protection Design" (Høvik, Norway : DNV GL, 2010). TED HUCK, an electrical engineer, is vice president international with MATCOR, Inc., 101 Liberty Ln., Chalfont, PA 18914, e-mail: thuck@matcor.com. He has 20-plus years of experience in technical sales, where he developed strong expertise in the application of CP. His diverse experi- ence with CP spans more than 13 years with MATCOR. Huck has authored over a dozen articles in a wide range of publica- tions, and is a frequent presenter at corro- sion conferences in the United States and internationally, including Amsterdam, Moscow, Istanbul, Bahrain, Mumbai, Seoul, Beijing, Chengdu, and Calgary. Huck holds an M.B.A. in finance from Texas Christian University and a B.S. degree in electrical engineering from Kettering University (formerly General Motors Institute). SHAILESH JAVIA is an electronics engineer and CP division head with SGB Scaffolding and Industrial Services Private Limited, 106, Sakar-V, B/h. Natraj Cinema, Opp. H . K . C o l l e g e , A s h r a m Rd . , A h m e d- abad–380009, Gujarat, India, e-mail: sjavia@beis.com. He has 24 years of corro- sion engineering and CP expertise. His diverse portfolio of CP system designs and turnkey CP projects includes cross-country pipelines; refineries; fertilizer, petrochemi- cal, and power plants; tanks and vessels; and city gas pipelines. In addition, Javia has expertise in post-commissioning sur- vey work and handling complex interfer- ence problems on cross-country pipelines. Javia has presented papers in Spain, Kuwait, Thailand, United Arab Emirates, Bahrain, and India. He is a NACE Interna- tional-certified Cathodic Protection Tech- nologist, has successfully completed the NACE direct assessment course, and has presented several papers at NACE and ASME conferences. Javia graduated from Amravati University in India with a B.E. degree in electronics engineering. Impressed Current Anode Systems for Jetty Piling Protection