In 1989 I wrote a paper with

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1 NACE INTERNATIONAL CATHODIC PROTECTION TRAINING & CERTIFICATION NEWS Summer 2013 The Future as a Reflection of the Past By John H. Fitzgerald III, FNACE, MP Technical Editor In 1989 I wrote a paper with this same title for an ASTM symposium on soil corrosion. 1 In it I showed how the technology and instrumentation of the early 20th century influenced the growth of knowledge and testing procedures up to the present time. Some recent reading brought that paper to mind. That reading was Twenty Thousand Leagues under the Sea by Jules Verne. Writing in the mid-19th century, Verne is known as the founder of science fiction. This book tells the story of Captain Nemo who, with his crew of like-minded men, had given up living on land and pursued their lives in a submarine. Capt. Nemo was a devoted oceanographer and discovered many things in his travels under the sea. The device that struck me was his method of determining the temperature of the sea around him. He had an iron bar the dimensions of which had been measured at 25 C (his baseline data). The bar was kept outside the submarine and drawn into the interior for a temperature measurement. By precisely measuring the bar s dimensions, and knowing the expansion coefficient of iron, Nemo could then make an indirect measurement of the temperature. That indirect temperature measurement reminded me of my 1989 paper. To me the iron bar, 150 years ago, was a precursor of the electric resistance (ER) corrosion probe with which we can make an indirect measurement of corrosion rate by measuring the change in resistance of the probe. The ER probe consists of a metal probe that can be inserted into liquids or the soil. As the probe corrodes, its cross sectional area reduces and its resistance increases. By comparing the resistances over a period of time, one can calculate the rate of corrosion of the metal using a Corrosimeter or similar instrument. My first experience with using corrosion probes was as reference electrodes under the bottoms of two new asphalt tanks. The tanks were to be built on a ring wall with an Trade Name impervious membrane about two ft (0.6 m) below the tank bottoms. Cathodic protection (CP) for the exterior of the bottom was provided by two deep anode groundbeds adjacent to the tanks. It was well known then that reference electrodes were needed under the tank to ensure proper CP coverage. The civil engineers advised us that the temperature at the anode level would be about 300 F (150 C). That would fry copper sulfate (CuSO 4 ) and might passivate zinc. We determined that corrosion probes would operate properly at that temperature, so we had three of them with high temperature-resistant cabling made for each tank. The probes IN THIS ISSUE... Continued on p. 3 The Future as a Reflection of the Past... 1 Free Corrosion App Takes NACE Mobile... 4 Call for NACE Instructors... 5 Corrosion Basics: Corrosion and Cathodic Protection... 6 NACE CP Course Schedule... 9 CP-Related Technical Committees CP-Related NACE Reports and Standards Summer 2013 Stay Current 1

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3 Continued from p. 1 were placed on the backfill about 1 ft (0.3 m) below the level of the bottom, backfilling was completed, and the tank was erected. Baseline data were obtained after the tanks were filled with asphalt. Subsequent annual measurements yielded data that indicated no appreciable change from the baseline data. Thus, the rate of corrosion of the probes was essentially zero, indicating effective CP. ER probes have been used for many years in vessels and pipelines containing corrosive liquids, often to determine the effectiveness of corrosion inhibitors. In some instances a small rate of corrosion may be acceptable. Here again ER probes are used to determine the actual rate of corrosion that is occurring. The actual rate can be compared to the acceptable rate to determine if the measured rate is within acceptable limits. ER probes are also used in test stations for underground or submerged structures. The probes are usually used in conjunction with coupons. Coupons (of the same metal as the structure) are connected to the structure through a switch, which permits instant off potential readings to be obtained. The ER probe in a test station provides the same data as shown above for the asphalt tanks. If the rate of corrosion is essentially zero, one can be assured that adequate CP is being received at that location. Alvin Toffler, in his book Future Shock, states that scientific knowledge doubles every 10 years. Corrosion control is no exception. If you have the opportunity to attend one of the many corrosion short courses that occur around the country each year, the annual NACE conference, or a NACE area conference, be certain to visit the exhibits. You will see some instruments and technologies that didn t exist even a year ago. Many of these are used to measure corrosion rates by indirect means, as does the ER probe. We will see many new developments in the years to come that are based on older information and techniques. So indeed, the future reflects the past, even back to Capt. Nemo s temperature measuring rod in the mid-19th century! SC Reference 1 J.H. Fitzgerald III, The Future as a Reflection of the Past, Effects of Soil Characteristics on Corrosion, ASTM STP1013, V. Chaker and I.D. Palmer, eds. (West Conshohocken, PA: ASTM, 1989), pp Summer 2013 Stay Current 3

4 Free Corrosion App Takes NACE Mobile Available for iphone, ipad, and Android By Jessica Baris, NACE International Content Specialist Whether you re in the office, on the road, or on a job site, take NACE International s free Corrosion App with you. The new app is now available at the itunes Store and Google Play for iphone, ipad, and Android OS 4.0 or higher. Members, registered nonmembers, and the general public have access to the free NACE Corrosion App. The app s features include calculators for cathodic protection (CP) and coatings professionals, a searchable directory of NACE International Institute certification holders worldwide, access to the NACE Career Center where users can view listings of open positions, an event calendar, NACE publications, and a complete course schedule with a search function for find- ing classes offered globally. NACE members have access to additional features, including their personal profiles, certification status, grade information, on-file applications, Materials Performance, the NACE membership directory, and notification when it s time to renew individual membership. Using feedback from corrosion industry professionals, we created an app that provides quick, easy access to NACE information and tools, says NACE Executive Director Bob Chalker. The app s nearly 60 calculators include a unit converter; anode resistance and galvanic anode calculators; coatings calculators including dew point, coatings coverage, and pressure drop in fluid hose; and electricity calculators including Ohm s Law. The toolset also includes 10 coatings charts for quick reference. CP professionals are constantly on the go, says Chalker. A CP technician can use the app to get a quick unit conversion; an operator seeking training opportunities for personnel can search nearby course offerings. The app makes it easy to get information immediately wherever you are. SC The app s nearly 60 calculators include a unit converter; anode resistance and galvanic anode calculators; coatings calculators including dew point, coatings coverage, and pressure drop in fluid hose; and electricity calculators including Ohm s Law. 4 Stay Current Summer 2013

5 Call for NACE Instructors At a time of unprecedented growth for NACE International membership now exceeds 30,000 worldwide NACE education and training programs and courses are rapidly increasing to keep pace with industry requirements. As much of the world s infrastructure nears or reaches the end of its design life, qualified corrosion professionals are in high demand to design and execute effective corrosion control systems using best engineering practices. NACE training and certifications are being specified more often and in more places NACE International contracts with hundreds of instructors who teach courses all over the world. as companies work to prevent safety, environmental, and economic problems that result from corrosioninduced failures. As NACE increases its course offerings, the need for new instructors from both inside and outside North America is growing to broaden the current strong network of training professionals. Becoming a NACE instructor involves a series of steps and qualifications that vary according to the course taught. Once qualified, instructors may get assignments in various parts of the world. For information on how to become a NACE instructor, contact NACE Education Senior Manager Pam Nicoletti at or pam.nicoletti@nace.org. SC Summer 2013 Stay Current 5

6 Corrosion Basics: Corrosion and Cathodic Protection The following article is an excerpt from the NACE International publication, Corrosion Basics An Introduction, Second Edition (: NACE, 2006). The four basic elements of a corrosion cell are an anode, a cathode, and the metallic and electrolytic pathways between them. Corrosion control can be achieved by eliminating (or reducing) any of these elements. One such method is to modify the electrolytic pathway by introducing a barrier between the threatened metal surface and the corrosive medium (i.e., by applying some kind of coating). If all metal surfaces could be coated with a material that was absolutely waterproof and absolutely free of flaws (holidays), all attack would be stopped. It should be noted that these two properties would have to be permanent without degradation. Unfortunately, no combination of coating materials and painstaking application can ensure a perfect coating indefinitely. However, there are modern coatings that approach perfection, at progressively higher costs. It is often most practical to accept the inevitability of some coating flaws, where corrosion can be controlled by cathodic protection (CP). The costs associated with CP for various ranges of coating efficiency are well known. Therefore, it is possible to select a cost-effective combination of reasonably good coating and CP, bearing in mind that generally, it is not practical to increase the investment in higher quality coating beyond the related savings in CP costs. Therefore, several questions arise about the use of imperfect coatings: How good are they when used alone? What effect do they have on the progress of corrosion? How do they affect the need for CP? Unregulated Pipelines without CP Compared with a bare pipeline in the same environment, a coated line can be expected to have fewer leaks during its service life; however, the coated line may have its first leak sooner because corrosion activity may be concentrated at the limited surface area of small holidays. Under special circumstances, this effect can be even more pronounced. Suppose that after some years in operation a bare line develops a leak at the most aggressive location requiring repair or replacement. The corrosive environment would be compounded by the tendency of new steel to be more active (anodic) with respect to older steel, and the unfavorable ratio of anodic and cathodic surface areas results in a concentration of corrosion current and a greater corrosion rate. The decision to avoid this predictable situation by coating the replacement piping actually makes matters even worse! Because the coating is not perfect, some new steel will be in contact with the electrolyte, and the remaining corrosion current is further concentrated at a small surface area where failures may occur in a short time. Limited CP installations using sacrificial anodes, often called hot spot protection, can provide an inexpensive solution for this situation. In areas influenced by stray current, it is extremely important that a good coating be applied to the line in the area of current pickup (which is cathodic and not subject to attack) to increase electrical resistance and thus minimize the amount of current that will consume pipe metal when it discharges elsewhere. In cases of static stray currents (e.g., cathodic stray currents), the identification of pickup areas is relatively simple. However, where dynamic stray currents are involved (e.g., near direct current-powered transit systems), locations near tracks that accumulate stray current when a train is nearby may actually discharge current back to the rails when no load is in the area. Indiscriminately coating these locations without a full understanding of the stray current activity patterns can concentrate the reduced total current to intolerable densities. With CP The effect that coating has on CP requirements is simple and can be stated briefly: application of a coating greatly reduces the amount of current required to obtain protection. The reduction may run from as much as 99.8% for an extremely good coating to as low as 50% for a very poor, old, damaged coating. In addition, a good coating can significantly improve attenuation characteristics along a pipeline, greatly increasing the effective range for an individual source of protective current. SC 6 Stay Current Summer 2013

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9 NACE CATHODIC PROTECTION COURSE SCHEDULE JULY DECEMBER 2013 Coatings in Conjunction with Cathodic Protection November December 2-7 CP Interference August September November Maracaibo, Venezuela Madrid, Spain Abu Dhabi, U.A.E. CP1 Cathodic Protection Tester July August Liberal, KS Marabella, Trinidad September 9-14 September September October October November November November December Dammam, Saudi Arabia Kuala Lumpur, Malaysia Buenos Aires, Argentina Doha, Qatar CP2 Cathodic Protection Technician Maritime September 7-12 September 8-13 Dammam, Saudi Arabia September 29-October 4 CP3 Cathodic Protection Technologist September July Beijing, China October 6-11 August Jackson, MI October 7-12 Kuala Lumpur, Malaysia August Bogota, Colombia November 3-8 October 5-10 Dammam, Saudi Arabia November 4-9 Buenos Aires, Argentina October 6-11 November Doha, Qatar October Dammam, Saudi Arabia November November Honolulu, HI November Fahaheel, Kuwait November Abu Dhabi, U.A.E. December 1-6 December December 8-13 CP2 Cathodic Protection Technician CP4 Cathodic Protection Specialist July 28-August 2 July Madrid, Spain October Beijing, China July October 28-November 2 London, U.K. August 4-9 November Dammam, Saudi Arabia August Bogota, Colombia December 8-13 August For the most up-to-date course schedules and course information, visit Summer 2013 Stay Current 9

10 CATHODIC PROTECTION-RELATED TECHNICAL COMMITTEES CATHODIC PROTECTION-RELATED TECHNICAL COMMITTEES Committee STG 05 STG 30 TEG 016X TEG 022X TEG 024X TEG 043X TEG 166X TEG 179X TEG 197X TEG 262X TEG 338X TEG 363X TEG 368X TG 013 TG 018 TG 019 TG 023 TG 025 TG 045 TG 047 TG 049 TG 167 TG 168 TG 210 TG 284 TG 297 TG 356 TG 360 TG 362 TG 388 TG 404 TG 429 TG 430 TG 436 TG 438 TG 446 Title Cathodic/Anodic Protection Oil and Gas Production Cathodic Protection Cathodic Protection and Corrosion Control Research Development Corrosion Control Coordinating Committee DC Traction Stray Current Problems Reinforced Concrete: Cathodic Protection Cathodic Protection in Seawater Discussion of Current Topics Cathodic Protection Cathodic Protection: Pipe-Type Cable Interference Problems Cathodic Protection Monitoring: Use of Coupons Close-Interval Surveys and CP Surveys Electric Utility Transmission and Distribution Corrosion and Grounding: Discussion of Issues Review of NACE Standard RP Steel, Structural: Corrosion Control of Pilings in Nonmarine Applications Pipelines: Cathodic Protection of Concrete Pressure and Mortar-Coated Steel High-Voltage Direct Current (DC) Transmission: Effects on Buried or Submerged Metallic Structures Alternating Current (AC) Power Systems, Adjacent: Corrosion Control and Related Safety Procedures to Mitigate the Effects Reinforced Concrete: Anode Test Procedures Reinforced Concrete: Sacrificial Cathodic Protection of Reinforced Concrete Elements Reinforced Concrete: Test Methods for Cathodic Protection Elements Review of NACE SP Cathodic Protection Systems, Retrofit, for Offshore Platforms Cathodic Protection Coupon Technology Review of NACE SP Direct Current (DC) Operated Rail Transit and Mine Railroad Stray Current Mitigation Review Report 10B169 Reinforced Concrete: Stray Current-Induced Corrosion Piping Systems: Review of SP (formerly RP0169) Electrical Cables for Cathodic Protection Use: State-of-the-Art Report Cathodic Protection Rectifier Safety Nuclear Buried Piping Symbols Related to Cathodic Protection AC Corrosion on Cathodically Protected Pipelines: Standard Practice for Risk Assessment, Mitigation, and Monitoring Testing of Field-Grade Reference Electrodes Reinforced Concrete: Galvanic Anode Test Procedures Review and Revise as Necessary SP Stay Current Summer 2013

11 Cathodic Protection-Related NACE Reports and Standards Document Title State-of-the-Art Report: Criteria for Cathodic Protection of Prestressed Concrete Structures Electrochemical Realkalization of Steel-Reinforced Concrete A State-of-the-Art Report Sacrificial Cathodic Protection of Reinforced Concrete Elements A State-of-the-Art Report Stray-Current-Induced Corrosion in Reinforced and Prestressed Concrete Structures Cathodic Protection for Masonry Buildings Incorporating Structural Steel Frames State-of-the-Art Survey on Corrosion of Steel Piling in Soils Report on Corrosion Probes in Soil or Concrete Use of Reference Electrodes for Atmospherically Exposed Reinforced Concrete Structures Electrical Isolation/Continuity and Coating Issues for Offshore Pipeline Cathodic Protection Systems One Hundred Millivolt (mv) Cathodic Polarization Criterion AC Corrosion State-of-the-Art Corrosion Rate, Mechanism, and Mitigation Requirements Technical Report on the Application and Interpretation of Data from External Coupons Used in the Evaluation of Cathodically Protected Metallic Structures 10A392 Effectiveness of Cathodic Protection on Thermally Insulated Underground Metallic Structures (2006 Edition) 1E100 Engineering Symbols Related to Cathodic Protection (2012 Edition) 6A100 Coatings Used in Conjunction with Cathodic Protection 7L192 Cathodic Protection Design Conderations for Deep Water Projects (2009 Edition) 7L198 Design of Galvanic Anode Cathodic Protection Systems for Offshore Structures (2009 Edition) SP / IS (modified) SP (formerly RP0575) SP (formerly RP0290) SP SP (formerly RP0177) SP (formerly RP0572) SP (formerly RP0286) SP (formerly RP0196) Petroleum and natural gas industries Cathodic protection of pipeline transportation systems Part 2: Offshore pipelines Internal Cathodic Protection (CP) Systems in Oil-Treating Vessels Impressed Current Cathodic Protection of Reinforcing Steel in Atmospherically Exposed Concrete Structures Electrochemical Realkalization and Chloride Extraction for Reinforced Concrete Mitigation of Alternating Current and Lightning Effects on Metallic Structures and Corrosion Control Systems Design, Installation, Operation, and Maintenance of Impressed Current Deep Anode Beds Electrical Isolation of Cathodically Protected Pipelines Galvanic Anode Cathodic Protection of Internal Submerged Surfaces of Steel Water Storage Tanks CATHODIC PROTECTION-RELATED NACE REPORTS AND STANDARDS RP SP (formerly RP0186) RP SP (formerly RP0100) SP (formerly RP0169) SP (formerly RP0207) External Cathodic Protection of On-Grade Carbon Steel Storage Tank Bottoms Application of Cathodic Protection for External Surfaces of Steel Well Casings The Use of Coupons for Cathodic Protection Monitoring Applications (ANSI approved) Cathodic Protection to Control External Corrosion of Concrete Pressure Pipelines and Mortar-Coated Steel Pipelines for Water and Waste Water Service Control of External Corrosion on Underground or Submerged Metallic Piping Systems Performing Close-Interval Potential Surveys and DC Surface Potential Gradient Surveys on Buried or Submerged Metallic Pipelines Summer 2013 Stay Current 11

12 1440 South Creek Drive Non Profit Org. U.S. Postage PAID Permit No. 579 Lebanon Junction, Kentucky Cathodic Protection-Related NACE Reports and Standards (continued) Document SP (formerly RP0285) SP (formerly RP0387) SP (formerly RP0388) SP (formerly RP0408) TM TM TM TM TM TM TM TM TM Title Corrosion Control of Underground Storage Tank Systems by Cathodic Protection Metallurgical and Inspection Requirements for Cast Galvanic Anodes for Offshore Applications Impressed Current Cathodic Protection of Internal Submerged Surfaces of Carbon Steel Water Storage Tanks Cathodic Protection of Reinforcing Steel in Buried or Submerged Concrete Structures Measurement Techniques Related to Criteria for Cathodic Protection on Underground or Submerged Metallic Tank Systems Measurement of Protective Coating Electrical Conductance on Underground Pipelines Test Procedures for Organic-Based Conductive Coating Anodes for Use on Concrete Structures Testing of Catalyzed Titanium Anodes for Use in Soils or Natural Waters Aboveground Survey Techniques for the Evaluation of Underground Pipeline Coating Condition Impressed Current Laboratory Testing of Aluminum Alloy Anodes Durability Test for Copper/Copper Sulfate Permanent Reference Electrodes for Direct Burial Applications Testing of Embeddable Impressed Current Anodes for Use in Cathodic Protection of Atmospherically Exposed Steel-Reinforced Concrete Measurement Techniques Related to Criteria for Cathodic Protection on Underground or Submerged Metallic Piping Systems Join NACE International and obtain unlimited free downloads of NACE standards and reports! For information on joining NACE, or to purchase standards and reports if not a member, go to 12 Stay Current Summer 2013