You may have seen an old railroad

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1 NACE INTERNATIONAL CATHODIC PROTECTION TRAINING & CERTIFICATION NEWS Fall 2013 Look Out for the Trains! By John H. Fitzgerald III, FNACE, MP Technical Editor You may have seen an old railroad crossing sign that said, Look Out for the Cars. I have, and thought it would have been much better to say, Look Out for the Locomotive. After all, the locomotive comes first and is much heavier than any of the cars. There are times when we not only have to look out for the cars but also for the trains, particularly in pipeline work. I learned this many years ago when I was a young corrosion engineer. This was long before close interval surveys and any of the other modern techniques for doing pipe-to-soil surveys on pipelines. While working in some very flat country somewhere in the Midwestern United States, I was doing a survey on a pipeline that was under impressed current cathodic protection. The technique we used then was to take a reading at each test station and then about four readings between that test station and the next. With two people on the job, that was fairly easy. One person set up at the test station and the other took the half cell out along the pipeline. This was in the days of using the big multimeters that had a potentiometer-volt meter (PM-VM) circuit. These instruments had a high resistance (HR) and a low resistance (LR) meter. You would zero the LR meter and then read the potential on the HR meter. The neat thing about these meters was that as soon as you had the reading, you could wave to the person carrying the half cell; the reading on the HR meter would remain stationary while the LR meter would swing to the right. That gave you time to record the reading (no data pods in those days everything was manual!), while the person with the half cell moved on to the next test point. As soon as the LR meter swung back toward zero, you knew the half cell was in the ground again, so you zeroed the LR meter and took the next reading. Now there were many times when two people were not available, so you did the whole job alone. That meant carrying the meter, a spool of wire, and the half cell from one test station to a point about halfway to the next one. Then you wound up the wire, returned to the first test station, and went on to the next one. Not very efficient at all, but lots of exercise! Continued on p. 3 IN THIS ISSUE... Look Out for the Trains!... 1 Procedures for Correct Connection of Cathodic Protection Rectifier Cables... 4 NACE Cathodic Protection Tester Course Goes Virtual with New Test Stations... 6 I AM NACE Profiles Spotlight Corrosion Career Stories of NACE Members... 8 NACE CP Course Schedule... 9 CP-Related Technical Committees...10 CP-Related NACE Reports and Standards...11 Fall 2013 Stay Current 1

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3 Continued from p. 1 This is what I was doing out there in that flat country in the center of our nation. I started at the test station at a road, and then proceeded along the right of way toward the next one. The test stations were not very far apart, and I could see the next one was a relatively short distance on the other side of a railroad track that ran perpendicular to the pipeline. I got to the railroad and looked carefully in both directions. I could see perhaps a mile up and down the track. There wasn t a train in sight. Realizing that I had only a couple hundred feet to go on the other side of the track, I carried the spool of wire over the tracks. Not good! I got beyond the railroad, and then I saw a train coming from way down the track. It was a passenger train and probably making better than 100 mph! I am sure you know the rest. Chop, chop. Most of my wire was Learn How to Extend the Operating Life and Integrity of Your Pipeline with the NACE INTERNATIONAL CATHODIC PROTECTION PROGRAM on the other side of the track and so was my connection to the pipe! As a result of this adventure, I modified my equipment so that I could pass the wire under the rails, and I never again lost any wire. Errata In the article, The Future as a Reflection of the Past in the Summer 2013 issue of Stay Current, it was incorrectly stated that the tanks under which the ER probes were used and which was underlain by an impervious membrane were protected by deep anode groundbeds. This is in error. The tanks were protected by a mixed metal oxide-titanium anode grid directly under the tank bottoms. We regret any inconvenience this error may have caused. SC MORE with NACE Fall 2013 Stay Current 3

4 Procedures for Correct Connection of Cathodic Protection Rectifier Cables Let s take some positive steps to be positive that the positive is always connected to the anodes! By W. Brian Holtsbaum, Corsult Associates (1980), Ltd. Labeling cables for correct polarity. The most serious mistake made in a cathodic protection (CP) impressed current installation is the reversal of the polarity of the direct current (DC) power source, most commonly a transformer-rectifier (rectifier). Every CP person knows the anode cable is connected to the positive terminal of the DC power source and the structure cable to the negative terminal. Unfortunately, outside the CP industry this practice is not well known or publicized. Most of these mistakes occur when the rectifier is being moved or cables are repaired. The cables were not previously labeled or were not properly identified when they were reconnected. The CP industry needs to develop a universal and highly publicized procedure to avoid this occurrence in the future. Consequences When the DC power source polarity is reversed, the structure becomes the anode and corrosion is accelerated. If the structure is steel, it is subjected to a corrosion rate of 9.1 kg/a-y (20.1 lb/a-y). On a coated structure, this steel will be lost at small coating holidays, thus a very rapid penetration of the wall of the structure occurs, resulting in multiple leaks and deep pitting over several kilometers (miles) of pipeline. The cost is not only the replacement of the structure but the costs of environmental cleanup, lost product, and the possibility of injury or loss of life. The owner is not happy that the CP installation intended to prevent corrosion actually caused more serious corrosion, and he is now facing not only the cost of the replacement but the cost of environmental restoration. Regardless of the way the cables are connected, when the rectifier is energized, the voltmeter and ammeter respond normally. However, this only indicates that the unit is functioning properly. These readings do not indicate that the external circuit polarity is correct. Procedure to Avoid Polarity Reversal A minimum procedure to avoid the possibility of polarity reversal of DC power sources would include: Requiring personnel with CP training to be present when a DC power source is energized Mandatory tests while energizing a CP DC power source Permanent identification of the DC cables Training Persons in many jurisdictions must be trained, qualified, and certified to work on a rectifier. A journeyman electrician is certified, but without specific training in CP, the electrician would not be qualified to confirm the correct polarity. That is, the electrician is familiar with the local electrical code, but most electrical codes do not cover the required polarity of the CP installations. Only a journeyman electrician is certified to connect the alternating current (AC) supply to a rectifier. Depending on the jurisdiction, a CP person who is not an electrician may have to be qualified and certified to work on the DC side of the power source. Any personnel, including electricians coming in contact with a rectifier or other DC power source, 4 Stay Current Fall 2013

5 should be trained in CP. Otherwise, instructions must be given to the electrician that a qualified CP person must be on site to supervise and test the final installation or repair of the DC cables. If a qualified CP person is not present, instructions are to be given to the electrician both verbally and in writing that the CP DC power source (rectifier) is not to be energized until a CP person completes the appropriate tests. A dedicated lockable AC disconnect should be installed within a reasonable distance and in sight of the rectifier for a CP-trained person to be able to lock out the supply and avoid inadvertent energization by another party. (In one jurisdiction this distance is 9 m.) A DC power source that has not been tested for polarity should be locked out until such a test is completed. Mandatory Testing before and after Energization Owners and CP providers must make testing for correct polarity a mandatory practice before a newly installed or repaired CP installation is energized. The CP person that energizes the rectifier must test and document the following information before leaving the site: Identify the cables by either potential and/or continuity tests. Confirm that the cables are connected to the correct terminal. Confirm that the cables have been properly identified. Most importantly, measure the structure-to-electrolyte potential with the DC power source on and off. Confirm that the potential becomes more electro-negative when the DC power source comes on. If the structure becomes more electropositive, the DC power source is to be turned off and locked out until the polarity is corrected. A polarity measurement at the DC output only confirms that the DC output is accurate but does not confirm that the cables are connected correctly or that they have not been switched underground. The measurement of an on and off potential is the only definite method to confirm that the polarity of the CP installation is correct. Cable Identification Cable Color Codes Each country has an electrical color code for cable circuits that must be met. First confirm the code for the area of the installation. For example, the CSA C22.1, Canadian Electrical Code (Section 4-036), requires the color code of DC cables to be one black and one red or one black and one white (grey, or white with a colored stripe). Unfortunately this code does not specify which is positive or negative. The cable used in the CP industry is small compared to the electrical industry and special orders are more expensive, thus the readily available black cable has been commonly used for the CP positive cable in the past. Most electricians and electronic technicians are familiar with red as positive and negative as black. If an electrician who is not familiar with CP connects the DC cables, there is a good chance that the black cable will be considered as the negative cable and connected to the negative terminal of the rectifier. As an industry we often do not provide much assistance to the electricians by using colors inconsistent with their normal practice. Color coding with different colored electrical tape has been used for identification and can be successful if the people involved understand the coding. CP Cable Labels Permanent labels identifying the polarity and facility need to be attached to every cable inside the DC power source so that if they are removed, the cable is clearly identified for the positive or negative terminal (refer to the photo on p. 4). If more than one circuit exists in the rectifier, the cable should be identified by the applicable circuit and by polarity. The labels need to be attached in such a manner that they are not removed if the cables are pulled out of the rectifier case or conduit. The labels could match the label on the DC power panel. Summary A reversed polarity of the CP DC power source output cables is recognized within the industry as a gross error causing accelerated corrosion but it is not well known or publicized outside of the industry. A standard practice must be established to avoid this error. 1. Establish a common practice requiring only a qualified CP person can energize a rectifier after appropriate tests confirming the correct polarity have been conducted. 2. Identify the DC output cables by a color code and labels. SC A version of this article was published in the December 2013 issue of MP. Owners and CP providers must make testing for correct polarity a mandatory practice before a newly installed or repaired CP installation is energized. Fall 2013 Stay Current 5

6 NACE Cathodic Protection Tester Course Goes Virtual with New Test Stations Students learn to use a new virtual test station available on a laptop. The program enables students to see how potentials can vary along a pipeline, and then analyze them to assess the effectiveness of the CP system. Students at a recent NACE International Cathodic Protection (CP) Tester course completed beta testing of the new virtual test stations that are now part of the course. The virtual test stations are laptop computers installed with custom software designed to replace the water-filled tub type stations. Students practice a variety of tasks, including measuring structure-to-electrolyte potentials, shunt readings, electrical circuits, and soil resistivity measurements. What s great about these virtual test stations is that the program gives consistent readings for every student, says NACE Course Development Manager Paula McCordic. The tub test stations previously used in the class were a challenge because the environments of each station changed over the course of the day. Students would test and get results very different from what other students were getting. For a classroom setting, it s important for students to be able to compare their results and for the instructor to have consistency across the board. The virtual test stations solve that. CP Instructor W. Brian Holtsbaum adds that the virtual test stations give the instructors more options for presenting students with a variety of real-life situations. The virtual test stations allow students to see how potentials can vary along a pipeline, and then analyze these potentials to assess the overall condition of the pipeline CP system. The instructor can also use the software to adjust the conditions of the pipeline so that students can conduct multiple tests and gain experience by obtaining a variety of results. The computers boost classroom practice time and another plus is that the software is loaded onto the computers, so there is no dependence on an Internet connection for them to work, says CP Instructor Jerome Edinger. The instructors spend less time preparing and stabilizing the equipment, which leaves more time to help students. It is a good thing for both students and instructors. NACE members Holtsbaum, Randall Webb, Raul Castillo, and Charlie Henderson assisted in the development and testing of the software. The virtual test stations are expected to be implemented in all CP Tester courses within the next year. Future features of the virtual test stations may include student tracking, reporting, and grading options. In addition to practice time on the virtual test stations, the course will continue to include a field day for students to do hands-on practice. Students who complete the course and pass the CP Tester exam earn CP Tester certification. For more information on NACE certification, visit the NACE Institute at SC 6 Stay Current Fall 2013

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8 I AM NACE Profiles Spotlight Corrosion Career Stories of NACE Members Careers in corrosion control and prevention are unfamiliar to most job seekers, but there are few professions with as much steady growth, rising salary averages, and opportunities to make a positive impact on public safety and the environment. Demand for corrosion professionals is increasing at the same time a wave of retirements is anticipated; the industry needs more qualified professionals. To help inform prospective corrosion professionals about what it s like to work in the industry, NACE International has created I AM NACE, a series of video interviews and online profiles that highlight individuals working in a variety of corrosion professions. Many of the stories include insight into how NACE training, certification, and membership activities have impacted and supported individuals at various stages of their careers. Each profile features professionals like the lead scientist at NASA s Kennedy Space Center Corrosion Technology Laboratory; a coatings inspector who tells of his experience completing work on Three Mile Island; a student pursuing a career in the oil and gas industry; and engineers, scientists, and other professionals in a range of industry sectors. Additional profiles will be added to the Web site each month. Our members do a wide range of interesting and challenging jobs, says NACE Executive Director Bob Chalker. Each profile is a window into the life of a real corrosion professional. The I AM NACE story-sharing program provides an opportunity to learn what it s like to work in the corrosion field. The annual global cost of corrosion is more than 3% of the world s GDP (approximately U.S. $2.2 trillion). It is estimated that at least one-third of this cost is preventable with the application of existing corrosion control technologies. SC To view the career stories, visit www. nace.org/i-am-nace. Corrosion professionals interested in sharing their career stories can iamnace@nace.org. Your full-service CP provider. Core Services: Cathodic Protection Engineering and Design Cathodic Protection Installation Cathodic Protection Materials and Equipment Sales Cathodic Protection System Monitoring and Maintenance Close Interval Surveys and ACVG / DCVG Coating Surveys Offices in: Billings, Montana Williston, North Dakota Wamsutter, Wyoming With customers stretching across the Rocky Mountain and Mid-Continent regions, we provide exceptional service and quality materials while maintaining a sharp focus on safety and customer satisfaction. Call us at (406) Stay Current Fall 2013

9 NACE CATHODIC PROTECTION COURSE SCHEDULE JANUARY JUNE 2014 COATINGS IN CONJUNCTION WITH CATHODIC PROTECTION January 5-10 February April June 1-6 CP INTERFERENCE January March 31-April 5 Calgary, AB, Canada Bogota, Colombia CP1 CATHODIC PROTECTION TESTER February March 2-7 March March 29-April 3 April April 27-May 2 May 4-9 Mumbai, India Dammam, Saudi Arabia Tulsa, OK February February March April 5-10 April April May 4-9 May 4-9 May May May May June 8-13 June 8-13 June Chicago, IL Mumbai, India Dammam, Saudi Arabia Bogota, Colombia Rosebush, MI Tulsa, OK Kilgore, TX Cuernavaca, Mexico Mumbai, India Downey, CA Kuala Lumpur, Malaysia CP2 CATHODIC PROTECTION TECHNICIAN MARITIME May 4-9 May Claysville, PA Kilgore, TX April 27-May 2 CP3 CATHODIC PROTECTION TECHNOLOGIST May Cuernavaca, Mexico January San Bernardino, CA May Mumbai, India January May Quito, Ecuador February 1-6 Cairo, Egypt June 1-6 Downey, CA March 30-April 4 June 1-6 April 5-10 Fahaheel, Kuwait June 9-14 Kuala Lumpur, Malaysia June CP2 CATHODIC PROTECTION TECHNICIAN CP4 CATHODIC PROTECTION SPECIALIST January San Bernardino, CA February January Fahaheel, Kuwait April Fahaheel, Kuwait February April 27-May 2 February For the most up-to-date course schedules and course information, visit Fall 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 430 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 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 10B189 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 AC Corrosion on Cathodically Protected Pipelines: Standard Practice for Risk Assessment, Mitigation, and Monitoring Reinforced Concrete: Galvanic Anode Test Procedures Review and Revise as Necessary SP Stay Current Fall 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 Fall 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 Fall 2013