ECDA and Cathodic Protection

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1 Volume 1, Issue 1 NACE CATHODIC PROTECTION TRAINING & CERTIFICATION NEWS Spring 2005 ECDA and Cathodic Protection by W. Brian Holtsbaum P.Eng., CC Technologies Canada Ltd. How does cathodic protection (CP) fit into ECDA (External Corrosion Direct Assessment) 1? ECDA is a structured process that is intended to improve safety by assessing and reducing the impact of external corrosion on pipeline integrity 1. Pipeline operators have historically managed their external corrosion control programs using many of the tools used in an ECDA program. This program now integrates the pipeline information, historical data, CP testing and inspections into one coordinated program. INSIDE THIS ISSUE ECDA and Cathodic Protection... 1 Letter from the Chairman... 3 PCIM Program in Development... 4 CP Standards Development... 5 CP Course Schedule and Stats... 6 NACE CP Standards NACE International The ECDA process requires the integration of data from multiple sources including a knowledge of pipeline construction, operating practices, environmental considerations, corrosion control, leak history and field examinations of pipe surfaces. Further testing or indirect examination to predict coating holidays at locations where corrosion is expected then enhances this information. Once sites suspected of corrosion are determined, a direct examination is conducted. Following the direct inspection a final assessment of all of the information gathered during the process is completed. This essentially brings all of the pipeline external corrosion control technology under one coordinated program. ECDA is a continuous improvement process that may take successive applications to identify areas of corrosion activity. The first ECDA on a pipeline provides a baseline with subsequent ECDA examinations improving the accuracy of the process. The process is illustrated by Figures 1a and 1b in NACE RP ECDA has the advantage of investigating pipeline integrity where other methods such as in-line inspection are impractical. It also aims at predicting corrosion before it has an opportunity to develop serious metal loss features. An ECDA is completed in four steps including: Pre-assessment Indirect Inspection Direct Examination Post Assessment Pre-assessment collects and reviews all historical data that is available to decide if ECDA is feasible and if so, defines specific ECDA regions and the indirect inspection methods. Indirect inspection consists of aboveground tests to define coating holidays and areas of corrosion activity. Direct examination combines the data from the pre-assessment and the indirect inspections to identify sites for excavation and inspection. A detailed inspection of the pipeline coating, pipe surface and soil conditions is then made. Post assessment combines all data available from the preceding steps to either confirm the pipe integrity or to establish further investigations until pipeline integrity is satisfied. During the Pre-assessment, the ECDA process requires that data be collected in a minimum of five categories including: Pipe-related Construction-related Soils/environment Operations Corrosion protection and Pipeline Operations The proper documentation of CP records is very important in the pre-assessment step in addition to any record of corrosion. A very important part of the Pre-assessment is to establish whether or not the ECDA process is applicable to each section of pipeline. It would be unfortunate if ECDA received a bad reputation because it was being applied to inappropriate situations. For example, an ECDA is not applicable to pipe inside a shorted road casing as the environment in the annular space is unknown and the above ground indirect inspections cannot be relied on to provide an indication of the status of the pipe inside the casing. continued on page 2 ECDA Volume 1 Stay Current 1

2 continued on page 2 ECDA Figure 1 ON/OFF potentials affected by stray current 2 The pipeline is then divided into regions depending on the different environmental conditions or characteristics of the pipeline. The tools to be used in the indirect inspection of each region are also selected during the pre-assessment phase. These tools include, but are not necessarily limited to, a close interval potential survey (CIS), Direct Current Voltage Gradient (DCVG), Alternating Current Voltage Gradient (ACVG), and coating integrity tests. These are tests that would normally be conducted by CP personnel. The indirect assessment requires at least two of the above tools be used over the entire length of each ECDA region although it is wise to complete as many as are practical. After the tests are completed, indications are identified and aligned for comparison. The criteria to establish a classification is determined and the severity of each indication is classified as to severe, moderate or minor. Again, persons trained in CP are required in the direct examination phase. Prior to coating removal, the measurement of structure-toelectrolyte potentials and the measurement of soil resistivity should be made at the sites selected for inspection. Additional training is required for the remainder of the inspection including soil and water sampling, coating inspection, ph measurements, corrosion inspection, magnetic particle inspections and photographic documentation. During pre-assessment certain problems 2 Stay Current Volume 1 may become evident that need further investigation. A case history of an ECDA was published in MP that emphasized stray current mapping 2. The pipeline was subjected to interference effects due to stray current from the transit system. The ECDA pre-assessment selected the following tools for the indirect inspection: Pipe location and depth Electromagnetic technique to determine coating condition on a macro scale CIS DCVG Soil resistivity Stray current mapping The variation in structure-to-electrolyte potentials with time due to stray current in the case history made simple rectifier ON/OFF data difficult to interpret (Figure 1). A stray current mapping was then conducted as illustrated in Figure 2. Comparing changes in structure-toelectrolyte potentials due to stray currents along the pipeline and using specially designed software made an analysis possible Figure 3 Comparison of potentials to stray current 2 (Figure 3). A detailed explanation is given in the MP paper. 2 Although a specialized stray current mapping tool was not one of the usual indirect inspection tools, it became invaluable in this instance. One must therefore include all applicable tools to ensure the greatest accuracy in the final assessment. So finally answering the question raised at the beginning of this article, ECDA and CP fit like a glove. CP personnel should become familiar with the ECDA process and all of the CP-related tests. This familiarity will in turn strengthen the importance of performing regular CP testing that is an integral part of any eventual ECDA assessments. 1 NACE RP Pipeline External Corrosion Direct Assessment Methodology. 2 A Kacicnik, D. H. Warnke, G. Parker, Stray Current Mapping Enhances Direct Assessment of an Urban Pipeline, NACE Materials Performance, Volume 43 No. 6, June 2004, page 26. Figure 2 Illustration of Stray Current Mapping 2

3 Free Tutorial CORROSION/2005 Coatings Used in Conjunction with Cathodic Protection: A Primer Presented by Richard Norsworthy Lone Star Corrosion Services Co. Wednesday, April 6, to 11 a.m. This tutorial will present the fundamentals of coatings technology when used in conjunction with cathodic protection, including special considerations given to coatings selection, surface preparation, and coatings application (field and plant), testing, QC, inspection parameters, and causes of failures. For a full listing of all CP and Pipeline related activities at CORROSION/2005, go to www. nace.org/tracker and check Pipelines, Tanks, and Underground Systems. Welcome to Stay Current! We would also like to hear from you... This is the first issue of this newsletter and we look forward to continuing this newsletter for many years. Stay Current was designed for individuals who have participated in the NACE Cathodic Protection Training and Certification Program -at any level-and the goal is to help keep you informed of the latest technology and trends in cathodic protection and how they may affect you on a daily basis. We hope it will also be a means by which you can find answers to your questions, stay connected with others in your industry and help you find the resources you need to help you in your day-to-day work activities. If there is technology you think we need to know about send us a note. If you are looking for information on a particular topic, send us note. If you have a question and haven't been able to find the answer, send us a note. If you have had some interesting experiences doing cathodic protection work send us a note. Questions or comments can be submitted by to laura.bartlett@nace.org as well as the NACE Online link for Stay Current at We hope you enjoy Stay Current! Sincerely, Paul Nichols Chairman-NACE Cathodic Protection Subcommittee Did you like CP? Get one free! How would you like to attend a NACE CP course...on NACE? Sound interesting? All you need to do is send an to staycurrent@nace.org or send a fax to 281/ letting us know that you saw this ad and we will put your name into a drawing for a free course registration. To be eligible you must hold a (any) NACE CP certification. You can use the registration for any NACE CP course, the choice is yours. The free course must be taken before June 30, (The prize is transferable, but may not be resold. If the prize is transferred, the person receiving the prize must meet the same criterion.) Volume 1 Stay Current 3

4 Pipeline Corrosion Integrity Management (PCIM) Program in Development by Lori Davies, Course Developer, NACE International NACE is expanding its curriculum to include a new program focused on pipeline corrosion integrity. Current regulatory requirements and industry need for training in this area make this program a priority for NACE Education & Training. The program will have two tracks-a field track and an engineering track. The program will emphasize technology, industry standards, regulations and decision-making directly related to pipeline corrosion integrity management-finding corrosion and repairing it. There are course requirements for each level; existing NACE training courses will be incorporated into this program as well as new courses. Certification will be offered for each level; at this time certification requirements are not yet finalized for the program. PCIM Field will focus on remediation technology and field techniques for carrying out integrity assessments. The goal is to prepare a individual to: accurately collect data used for the evaluation and monitoring of a pipeline corrosion integrity plan including ECDA and ICDA methods and technologies. recognize pipeline anomalies. make recommendations for resolving technical issues in the ditch. recognize problems in the ditch and be able to collect the data necessary for further engineering evaluation. PCIM Engineer will focus on the implementation and management of an integrity program for a pipeline system. The focus of this level is on integrity verification and maintenance optimization. The goal is that an individual completing these courses should be capable of interpreting integrity related data, performing an overall integrity assessment on a pipeline system, calculating and quantifying risk, and making recommendations to company management on risk management issues. The PCIM program is in the early stages of development; however, plans are to begin offering the program in late 2005/early CP 1 Cathodic Protection Tester (prerequisites) CIP Level 2/CIP Session II (prerequisites) PCIM FIELD Field Techniques for External Corrosion Course *New course not yet developed Internal Corrosion for Pipelines Course Direct Assessment Course *New course not yet developed In-line Inspection Course *New course not yet developed PCIM ENGINEER PCIM Integrity Management Course *New course not yet developed 4 Stay Current Volume 1

5 Latest and Greatest NACE Standards Development for Cathodic Protection by Linda Goldberg, Director, Technical Activities NACE technical committees working in the areas of pipelines and cathodic protection (CP) have always been active, but the activity has increased a great deal in the last couple of years because of the new U.S. pipeline safety regulations. Responding to pipeline safety incidents and requests by industry and government, a number of Task Groups (TGs) have been formed to write pipeline-related documents. The first of this "new wave" of documents, NACE Publication 35100, "In-Line Nondestructive Inspection of Pipelines," a technical committee report analyzing and reviewing the capabilities of available and emerging technologies in the field of in-line inspection tools, was published in The report was a precursor to NACE Standard RP , "In-Line Inspection of Pipelines," which outlines a process a pipeline operator can use to plan, organize, and execute an in-line inspection (ILI) project. Recognition by the Office of Pipeline Safety (OPS) of direct assessment (DA) as an acceptable pipeline integrity management method has stimulated more work on NACE standards using the specific types of the four-step DA process. ANSI/NACE Standard RP , Pipeline External Corrosion Direct Assessment Methodology, was incorporated in Title 49 Code of Federal Regulations (CFR) Part 192, Subpart O, "Pipeline Integrity Management," and is also being incorporated in New York State regulations as part of New York's incorporation of the federal regulation. NACE Standard RP , Stress Corrosion Cracking (SCC) Direct Assessment Methodology, was recently published and is being considered for incorporation in the federal regulation, which is also expected with other NACE standards still under development. Draft standards for which publication is eagerly anticipated include Close-Interval Potential Surveys on Buried or Submerged Metallic Pipelines, by TG 279; Gas Transmission Pipeline Internal Corrosion Direct Assessment Methodology, by TG 293; Aboveground Techniques for the Evaluation of Underground Pipeline Coating Condition, by TG 294; External Corrosion Direct Assessment for Wet Gas Pipelines, by TG 305; and Internal Corrosion Direct Assessment for Liquid Petroleum Pipelines, by TG 315. There is so much interest in DA as a method for pipeline integrity management that Technology Exchange Group (TEG) 292X (Direct Assessment Methodology Application) was formed to discuss ECDA updates and changes. As operators employ DA, they are constantly learning new information, what works and what doesn't, and a list server has been set up to facilitate discussion including proposals for consideration for revision to NACE Standard RP0502 to be transmitted to the TG responsible for that standard. A proposed revision to the section on criteria for CP in NACE Standard RP , "Control of External Corrosion on Underground or Submerged Metallic Piping Systems," has generated widespread interest. RP0169 is the "granddaddy" of all NACE CP standards and one of the first standards published by NACE in 1969, and it has always been controversial. A Front- Page Issues session on the proposed revisions to the criteria, conducted by TG 285 and sponsored by the NACE Public Affairs Committee, at Corrosion Technology Week/2004 in September drew a standing-room-only crowd. TG 285 expects to have a draft for ballot soon. NACE Standard TM , "Measurement Techniques Related to Criteria for Cahtodic Protection on Underground or Submerged Metallic Piping Systems," was published in 1997 as a companion standard to RP0169, providing descriptions of the measurement techniques and cautionary measures most commonly used on underground piping to determine whether a specific criterion has been complied with at a test site. Its next revision will be due in Persons who wish to vote on any standards being developed by NACE technical committees may join any of the sponsoring Specific Technology Groups (STGs) for a TG developing a standard. NACE members may join technical committees online at: content/technical/techcomm/membership.asp, or by calling the Technical Activities Division at Nonmembers may also vote on standards by registering as a nonmember via the Technical Committees section of the Web site: balloting/index.asp. Specific Technology Group (STG) 35 on Pipelines, Tanks, and Well Casings administers 22 TGs assigned to write standards and reports. STG 05 on Cathodic/Anodic Protection also is active in standards development, administering 11 TGs involved in standard or report writing. STG 05 administers TG 285 on the criteria for RP0169, which is co-sponsored by STG 35. STG 05 also is responsible for NACE standards dealing with cathodic protection of water storage tanks; TG 167 just completed a revision of NACE Standard RP0196, "Galvanic Anode Cathodic Protection of Internal Submerged Surfaces of Steel Water Storage Tanks." Another well-known NACE standard that is due for review in 2005 is NACE Standard RP , "Mitigation of Alternating Current and Lightning Effects on Metallic Structures and Corrosion Control Systems." STG 03 on Coatings and Linings, Protective: Immersion and Buried Service also has a number of recently published standards and standards under development dealing with coating of pipelines. Because coatings are used in conjunction with CP, these standards may also provide useful information for CP personnel. Two recently published standards in this area include NACE Standards RP , "Field- Applied Heat-Shrinkable Sleeves for Pipelines: Application, Performance, and Quality Control," and RP , "Design, Installation, and Operation of Thermoplastic Liners for Oilfield Pipelines." If you have questions about NACE standards development, please contact Linda Goldberg at 281/ or linda.goldberg@nace.org. Volume 1 Stay Current 5

6 CP Course Schedule through June 30, 2005 Please note schedule is subject to change without notice. For the most current schedule of CP Courses visit CP 1 Cathodic Protection Tester March 13-18, Houston, TX... 05C46105 April 17-22, Marysville, MI... 05C46150 May 1-6, West, PA... 05C46116 May 8-13, Houston, TX... 05C46117 June 19-24, Louisville, KY... 05C46129 CP 2-Cathodic Protection Technician March 6-11, Pueblo, CO... 05C46218 April 17-22, Eagan, MN... 05C46207 April 24-29, Tulsa, OK... 05C46217 May 1-6, Chatham, ON... 05C46225 May 8-13, West Alexander, PA... 05C46219 CP 3-Cathodic Protection Technologist April 24-29, Houston, TX... 05C46318 June 19-24, Houston, TX... 05C46321 CP 4-Cathodic Protection Specialist May 1-6, Houston, TX... 05C46403 CP Stats The NACE Cathodic Protection program has seen a growth of 38% in student enrollment since it began in September 2000 with 473 students in and growing to 770 students in Average number of 699 students per year attending either an in-house program or a NACE Headquarters sponsored CP course each year since Total certified since September 2000: NEW IN 2004! CP Tester CP Technician CP Technologist CP Specialist The number of CP classes increased from 22 in to a record number of 60 classes in equaling a 63% increase! 6 Stay Current Volume 1

7 Highlights of CP Related Meetings at CORROSION/2005 (Please note this listing only highlights some of the CP-related technical meetings being held at CORROSION/2005. For a full listing of CP & Pipeline related meetings visit Sunday, April 3, 2005 Cathodic Protection Criteria: Review NACE Standard RP0169 Section 6 Criteria (TG 285) [05] [35] 9:00 a.m. to 5:30 p.m. Monday, April 4, 2005 Mortar-Coated Pipes: Cathodic Protection Criteria (TG 019) [05] [10, 35] 8:00 to 10:00 a.m. Tanks, Aboveground: External Cathodic Protection of On-Grade Metallic Storage Tank Bottoms (TG 013) [35] [05] 1:00 to 5:30 p.m. Cathodic Protection of Pipelines in Seawater (TG 169) [30] [05, 35] 1:00 to 3:00 p.m. Tuesday, April 5, 2005 Cathodic Protection: Report on the Application of the 100-mV Polarization Criterion (TG 211) [35] [05] 1:00 to 3:00 p.m. Reinforced Concrete: Cathodic Protection (TEG 043X) [01] 3:30 to 5:30 p.m. Wednesday, April 6, 2005 Symposia Direct Assessment Symposium (STG 35) 9:00 a.m. to 6:00 p.m. Cathodic Protection in Offshore and Marine Environments Symposium (STG 30) 1:00 to 5:30 p.m. Cathodic Protection (TEG 179X) [05] 1:00 to 5:30 p.m. Thursday, April 7, 2005 Symposia Cathodic Protection Criteria & Application Symposium (STG 05) 9:00 a.m. to 6:00 p.m. Cathodic Protection Monitoring: Use of Coupons (TEG 338X) [35] [05] 1:00 to 3:00 p.m. Volume 1 Stay Current 7

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