We have one week left to send your vote into NACE for the SP0169-2007 revision. Please let me know if there are any issues or questions. I will help if I can.
We have all worked very hard. There is much more work to do! Even after the first ballot, there will likely be a re-ballot or two, so please stay in tune with the process. If you would to see what I say in my negative vote I will be glad to forward it to you if it helps.
I have strongly defended the use of the -850 mV or more negative “ON” potential. I have found some data that backs up the thing I have been saying for a long time. It is very rare to no meet a 100 mV of polarization if you also have an “ON” -850 mV or more negative. Also, most corrosion we find today has little to do with inadequate CP and more to do with the coatings we have used and are still using in some cases. There is too much proof! Too many years of data! Put it in front of the committee and let them see it.
The issues that we face are many. Please keep in mind that there are several parts of the document, not just criteria. We must look at all parts of the document. I personally think the coatings section has been greatly improved, even though there are some problems, but these can be corrected.
Thanks again for all the support and effort. In the long run, we hope we have a document that will provide the industry with the best possible standard that will provide many more years of guidance to controlling the external corrosion on pipelines.
Richard Norsworthy
Tuesday, August 25, 2009
Dead Line Reminder!
DEADLINE REMINDER
YOU HAVE NOT RESPONDED TO THE TG 360 BALLOT AND THE DEADLINE IS FAST APPROACHING. PLEASE READ
THE INSTRUCTIONS BELOW AND CAST YOUR VOTE.
NACE International has extended hours for the customer service department from 7:00am to 7:00pm central time (GMT-06:00) to better serve our members! Call +1 281-228-6200 or 1-800-797-6223 for FirstService.
------------------------------------------------------------------------
OFFICIAL ONLINE BALLOT ON THE PROPOSED REVISION TO NACE SP0169-2007 (FORMERLY RP0169)
DEADLINE TO RESPOND: September 1, 2009
------------------------------------------------------------------------
Dear Members of STGs 35, 05, 30, and Interested Parties:
Cc: TCC
------------------------------------------------------------------------
Task Group (TG) 360’s proposed revision to NACE SP0169-2007 (formerly RP0169), “Control of External Corrosion on Underground or Submerged Metallic Piping Systems,” is now on the NACE Web site.
------------------------------------------------------------------------
DO NOT REPLY TO THIS E-MAIL. PLEASE FOLLOW INSTRUCTIONS BELOW:
------------------------------------------------------------------------
STEP 1: Please review the ballot by going to http://web.nace.org/ where you will view the NACE login page. You will be prompted to enter your user name and password. Once you have done so and are logged in, click on the tab in the upper right-hand corner titled “Committees.” Then, click on “Online Balloting” (on the right-hand column on this page). The next page you will see offers you Action Items, Results and a Logout option.
------------------------------------------------------------------------
STEP 2: The next page you will see is TCC Balloting Home.
To respond to ballots, click on the Action Items button. This will take you to a listing of open Ballots, Reballots, Review and Comments, and Canvasses. Find the appropriate TG number and click “Respond.”
STEP 3: To review the document prior to voting, click on the document title link at the top of the TCC Vote Response screen.
The document is in Adobe Acrobat PDF format, which means you will need Acrobat Reader software on your computer. If you do not have it, you may download it FREE from the Adobe Web site,
http://www.adobe.com/products/acrobat/readstep.html
STEP 4: After reviewing the document, you may vote by clicking the “Back” button at the top left corner of the screen and casting your vote on the TCC Vote Response page. Add any Editorial or Technical comments in the space provided. If you have no Technical and/or Editorial comments, please check the appropriate “I have no comments” box(es).
Be sure to click on the SUBMIT RESPONSE button at the bottom of the page to submit your vote.
After you have submitted your vote, the TCC Response Confirmation page will appear stating that your vote has been recorded. In addition, you will receive an e-mail confirmation of your vote.
------------------------------------------------------------------------
Thank you for your participation in the online balloting process.
YOU HAVE NOT RESPONDED TO THE TG 360 BALLOT AND THE DEADLINE IS FAST APPROACHING. PLEASE READ
THE INSTRUCTIONS BELOW AND CAST YOUR VOTE.
NACE International has extended hours for the customer service department from 7:00am to 7:00pm central time (GMT-06:00) to better serve our members! Call +1 281-228-6200 or 1-800-797-6223 for FirstService.
------------------------------------------------------------------------
OFFICIAL ONLINE BALLOT ON THE PROPOSED REVISION TO NACE SP0169-2007 (FORMERLY RP0169)
DEADLINE TO RESPOND: September 1, 2009
------------------------------------------------------------------------
Dear Members of STGs 35, 05, 30, and Interested Parties:
Cc: TCC
------------------------------------------------------------------------
Task Group (TG) 360’s proposed revision to NACE SP0169-2007 (formerly RP0169), “Control of External Corrosion on Underground or Submerged Metallic Piping Systems,” is now on the NACE Web site.
------------------------------------------------------------------------
DO NOT REPLY TO THIS E-MAIL. PLEASE FOLLOW INSTRUCTIONS BELOW:
------------------------------------------------------------------------
STEP 1: Please review the ballot by going to http://web.nace.org/ where you will view the NACE login page. You will be prompted to enter your user name and password. Once you have done so and are logged in, click on the tab in the upper right-hand corner titled “Committees.” Then, click on “Online Balloting” (on the right-hand column on this page). The next page you will see offers you Action Items, Results and a Logout option.
------------------------------------------------------------------------
STEP 2: The next page you will see is TCC Balloting Home.
To respond to ballots, click on the Action Items button. This will take you to a listing of open Ballots, Reballots, Review and Comments, and Canvasses. Find the appropriate TG number and click “Respond.”
STEP 3: To review the document prior to voting, click on the document title link at the top of the TCC Vote Response screen.
The document is in Adobe Acrobat PDF format, which means you will need Acrobat Reader software on your computer. If you do not have it, you may download it FREE from the Adobe Web site,
http://www.adobe.com/products/acrobat/readstep.html
STEP 4: After reviewing the document, you may vote by clicking the “Back” button at the top left corner of the screen and casting your vote on the TCC Vote Response page. Add any Editorial or Technical comments in the space provided. If you have no Technical and/or Editorial comments, please check the appropriate “I have no comments” box(es).
Be sure to click on the SUBMIT RESPONSE button at the bottom of the page to submit your vote.
After you have submitted your vote, the TCC Response Confirmation page will appear stating that your vote has been recorded. In addition, you will receive an e-mail confirmation of your vote.
------------------------------------------------------------------------
Thank you for your participation in the online balloting process.
What happened to NACE?
What happened to NACE?
You may remember “The National Association of Corrosion Engineers?” I wonder what those eleven men, corrosion engineers in the Pipeline Industry, would think of NACE today. A NACE that today finds itself in the position of writing Federal Code. A NACE that is contemplating changes to the core standard that has effectively and safely served the pipeline industry for the past 66 years. Prudent Operators have used the existing standard to protect the public and preserve valuable and critical assets.
I am not against revising the ST0169. I believe all standards should be under constant review with the goal of improving safety and asset preservation. Supporters of the revision argue that the off -.850 has scientific research behind it and contend that the on -.850 as put forth by Peabody has only empirical data to support it. How many leaks or ruptures have been associated with =<-.850 with current applied. The current revision being contemplated raises valid questions as to whether the off potential is a true IR free reading. Other’s who are far more qualified than I am have raised these questions and made convincing arguments and I will leave that to them.
My question is who should be reviewing and revising ST0169? If revised to the current recommendations this standard has the potential to add hundreds of millions of dollars to the cost of operating the country’s underground pipelines, and only bring about questionable improvements to safety. The stakeholders which include: the public whom the standard is designed to protect, the regulators who have the responsibility of codifying the standard, and the operators, who will have to absorb the cost of implementing the revised standard, should be debating, reviewing and revising the standard.
So back to my original question, what happened to NACE? When did we quit being an industry group with the goal of protecting the public and preserving the national asset that is the underground pipeline system? When did we decide that members who will be under no legal obligation nor incur the cost of complying with the standard get to set the standard? A quick glance at the membership roster of STG 35 shows only about 30% of the members are domestic operators. TG 360, about 30% of the members are domestic operators. Definition of Democracy “two wolves and a sheep voting on what’s for dinner”.
Whose fault is this? Mine, I am the corrosion practiconer working for a domestic operator who has decided that with budget pressures, expanding work load and shrinking staff , I am unwilling to dedicate the time to be actively involved in NACE except for the occasional trip to a conference.
I have been in the pipeline industry for over 30 years, and yet I recognize that with all of the scientific and technological advances made in the past 60 years it is time to move forward and take advantage of these tools. With the advent of high resolution ILI tools and the implementation of the IMP we have actual corrosion data for a segment of pipeline. Let’s incorporate this data into our compliance standard. Why expend time and resources to maintain an IR free -.850 or less with current applied to a segment of pipe that has no corrosion? With the baseline assessment nearing completion and reruns starting next year we will have accurate corrosion rates to work with. Give us credit for the hundreds of millions of dollars the industry has spent running high resolution ILI tools, give us credit for the hundreds of millions of dollars the industry has spent remediating to ASME B31.8S. Which would better ensure the safety and integrity of a section of pipeline, actual known corrosion data from an ILI or an electrical reading that at best tells us what the potential for corrosion is.
To summarize, if we are going to revise ST0169 then let’s revise it using all of the technological and scientific advances available to us today.
Kerry L. Morgan
Senior Corrosion Technologist 5037
NACE 133125
You may remember “The National Association of Corrosion Engineers?” I wonder what those eleven men, corrosion engineers in the Pipeline Industry, would think of NACE today. A NACE that today finds itself in the position of writing Federal Code. A NACE that is contemplating changes to the core standard that has effectively and safely served the pipeline industry for the past 66 years. Prudent Operators have used the existing standard to protect the public and preserve valuable and critical assets.
I am not against revising the ST0169. I believe all standards should be under constant review with the goal of improving safety and asset preservation. Supporters of the revision argue that the off -.850 has scientific research behind it and contend that the on -.850 as put forth by Peabody has only empirical data to support it. How many leaks or ruptures have been associated with =<-.850 with current applied. The current revision being contemplated raises valid questions as to whether the off potential is a true IR free reading. Other’s who are far more qualified than I am have raised these questions and made convincing arguments and I will leave that to them.
My question is who should be reviewing and revising ST0169? If revised to the current recommendations this standard has the potential to add hundreds of millions of dollars to the cost of operating the country’s underground pipelines, and only bring about questionable improvements to safety. The stakeholders which include: the public whom the standard is designed to protect, the regulators who have the responsibility of codifying the standard, and the operators, who will have to absorb the cost of implementing the revised standard, should be debating, reviewing and revising the standard.
So back to my original question, what happened to NACE? When did we quit being an industry group with the goal of protecting the public and preserving the national asset that is the underground pipeline system? When did we decide that members who will be under no legal obligation nor incur the cost of complying with the standard get to set the standard? A quick glance at the membership roster of STG 35 shows only about 30% of the members are domestic operators. TG 360, about 30% of the members are domestic operators. Definition of Democracy “two wolves and a sheep voting on what’s for dinner”.
Whose fault is this? Mine, I am the corrosion practiconer working for a domestic operator who has decided that with budget pressures, expanding work load and shrinking staff , I am unwilling to dedicate the time to be actively involved in NACE except for the occasional trip to a conference.
I have been in the pipeline industry for over 30 years, and yet I recognize that with all of the scientific and technological advances made in the past 60 years it is time to move forward and take advantage of these tools. With the advent of high resolution ILI tools and the implementation of the IMP we have actual corrosion data for a segment of pipeline. Let’s incorporate this data into our compliance standard. Why expend time and resources to maintain an IR free -.850 or less with current applied to a segment of pipe that has no corrosion? With the baseline assessment nearing completion and reruns starting next year we will have accurate corrosion rates to work with. Give us credit for the hundreds of millions of dollars the industry has spent running high resolution ILI tools, give us credit for the hundreds of millions of dollars the industry has spent remediating to ASME B31.8S. Which would better ensure the safety and integrity of a section of pipeline, actual known corrosion data from an ILI or an electrical reading that at best tells us what the potential for corrosion is.
To summarize, if we are going to revise ST0169 then let’s revise it using all of the technological and scientific advances available to us today.
Kerry L. Morgan
Senior Corrosion Technologist 5037
NACE 133125
Tuesday, August 11, 2009
Joeberth Belarmino comments
Mr. Bash,
I appreciate very much your effort for making this Blog site, I also have a comment regarding the NACE RP0169 they have two criteria for adequate Cathodic Protection, the -850mV instant "off" and the 100mV polarized potential but in the industry they often refer only to the -850mV criteria and mostly forgetting the other reliable criterion which is the 100mV polarized potential, I believed there should only be one criterion if we really want to make a standard, the -850mV instant "off" is a confusion with the 100mV polarized potential
Joeberth Belarmino
REE/CP tech
I appreciate very much your effort for making this Blog site, I also have a comment regarding the NACE RP0169 they have two criteria for adequate Cathodic Protection, the -850mV instant "off" and the 100mV polarized potential but in the industry they often refer only to the -850mV criteria and mostly forgetting the other reliable criterion which is the 100mV polarized potential, I believed there should only be one criterion if we really want to make a standard, the -850mV instant "off" is a confusion with the 100mV polarized potential
Joeberth Belarmino
REE/CP tech
Thursday, July 2, 2009
We at Polyguard want to thank every one for their support and encouragment to keep this Blog site going. Though I do not always keep it up as often as I would like, We do feel it is an important issue that has not been as well publised as possible by NACE and others in the corrosion control industry.
Whether you agree or disagree with the revision, is not as important as the efforts to provide a format to "freely" discuss the issues involved with this document. At times we did not feel that format was available to many. Some do not have an opportunity nor want to face the committee and try to make their point. Small companies and operators do not always have the expertise to discuss many of the issues, yet know what they have been doing is working.
Please be sure that you get on "Join the Ballot Voting List" if you are a member of the required groups (STG 03, 05, 35 and 62). You may be able to join one of the groups before the dead line and then join the list to vote. I am not sure about this but some one at NACE will help you if needed.
I have held some of my comments about the various reasons why I am going to vote "NO" on the document, but will be glad to discuss with any of you or provide support for anyone or any company that also feels this is not a valid or good document as written.
I would like to thank the TG 360 committee and NACE for the very hard work and extra effort some have put in to get this document to this point. Whether we agree or disagree with where it is, we do all agree with the difficulty of undertaking such an important revision. What we all want is the best possible document for our industry.
Thanks again for the support,
Richard Norsworthy
Polyguard Products, Inc.
Whether you agree or disagree with the revision, is not as important as the efforts to provide a format to "freely" discuss the issues involved with this document. At times we did not feel that format was available to many. Some do not have an opportunity nor want to face the committee and try to make their point. Small companies and operators do not always have the expertise to discuss many of the issues, yet know what they have been doing is working.
Please be sure that you get on "Join the Ballot Voting List" if you are a member of the required groups (STG 03, 05, 35 and 62). You may be able to join one of the groups before the dead line and then join the list to vote. I am not sure about this but some one at NACE will help you if needed.
I have held some of my comments about the various reasons why I am going to vote "NO" on the document, but will be glad to discuss with any of you or provide support for anyone or any company that also feels this is not a valid or good document as written.
I would like to thank the TG 360 committee and NACE for the very hard work and extra effort some have put in to get this document to this point. Whether we agree or disagree with where it is, we do all agree with the difficulty of undertaking such an important revision. What we all want is the best possible document for our industry.
Thanks again for the support,
Richard Norsworthy
Polyguard Products, Inc.
Instructions for Joining the Ballot Voting List for SP0169
------------------------------------------------------------------------
JOIN THE BALLOT VOTING LIST (RESPOND TO THE CANVASS) FOR PROPOSED REVISION TO NACE SP0169-2007 (FORMERLY RP0169)
DEADLINE TO RESPOND: July 29, 2009
------------------------------------------------------------------------
Welcome to the TCC online balloting system that allows members to join a ballot voting list.
Dear Members:
------------------------------------------------------------------------
We are contacting members of STGs 35, 05, and 30 regarding their desire to vote on an upcoming ballot of TG 360’s proposed revision to NACE SP0169-2007 (formerly RP0169), “Control of External Corrosion on Underground or Submerged Metallic Piping Systems.”
------------------------------------------------------------------------
DO NOT REPLY TO THIS E-MAIL. PLEASE FOLLOW INSTRUCTIONS BELOW:
------------------------------------------------------------------------
STEP 1: Please review the abstract by going to http://web.nace.org/ where you will view the NACE login page. You will be prompted to enter your user name and password. Once you have done so and are logged in, click on the tab in the upper right-hand corner titled “Committees.” Then, click on “Online Balloting” (on the right-hand column on this page). The next page you will see offers you Action Items, Results and a Logout option.
------------------------------------------------------------------------
STEP 2: The next page you will see is TCC Balloting Home.
To join a voting list, click on the Action Items button. This will take you to a listing of open Ballots, Reballots, Review and Comments, and voting lists.
Under the heading “Join Ballot Voting Lists,” find the appropriate TG number and click “Respond.”
STEP 3: To review the abstract prior to responding, click on the document title link at the top of the page.
The abstract is in Adobe Acrobat PDF format, which means you will need Acrobat Reader software on your computer. If you do not have it, you may download it FREE from the Adobe Web site,
http://www.adobe.com/products/acrobat/readstep.html
STEP 4: After reviewing the abstract, you may join the voting list or decline to join by clicking the “Back” button at the top left corner of the screen and choosing “yes” or “no” on the TCC Ballot Response page. Please remember to indicate your classification.
NOTE: The interest classifications have recently been expanded. Previously, there were only three interest classifications (user, producer, general interest), but there are now seven (user/consumer, manufacturer/producer, general interest, contractor, consultant, government/military, and research, development, and testing). Please consider these classifications carefully.
Be sure to click on the SUBMIT RESPONSE button at the bottom of the page to submit your response.
After you have submitted your response, the TCC Response Confirmation page will appear stating that your response has been recorded. In addition, you will receive an e-mail confirmation of your response.
------------------------------------------------------------------------
Thank you for your participation in the online process of forming a voting list.
JOIN THE BALLOT VOTING LIST (RESPOND TO THE CANVASS) FOR PROPOSED REVISION TO NACE SP0169-2007 (FORMERLY RP0169)
DEADLINE TO RESPOND: July 29, 2009
------------------------------------------------------------------------
Welcome to the TCC online balloting system that allows members to join a ballot voting list.
Dear Members:
------------------------------------------------------------------------
We are contacting members of STGs 35, 05, and 30 regarding their desire to vote on an upcoming ballot of TG 360’s proposed revision to NACE SP0169-2007 (formerly RP0169), “Control of External Corrosion on Underground or Submerged Metallic Piping Systems.”
------------------------------------------------------------------------
DO NOT REPLY TO THIS E-MAIL. PLEASE FOLLOW INSTRUCTIONS BELOW:
------------------------------------------------------------------------
STEP 1: Please review the abstract by going to http://web.nace.org/ where you will view the NACE login page. You will be prompted to enter your user name and password. Once you have done so and are logged in, click on the tab in the upper right-hand corner titled “Committees.” Then, click on “Online Balloting” (on the right-hand column on this page). The next page you will see offers you Action Items, Results and a Logout option.
------------------------------------------------------------------------
STEP 2: The next page you will see is TCC Balloting Home.
To join a voting list, click on the Action Items button. This will take you to a listing of open Ballots, Reballots, Review and Comments, and voting lists.
Under the heading “Join Ballot Voting Lists,” find the appropriate TG number and click “Respond.”
STEP 3: To review the abstract prior to responding, click on the document title link at the top of the page.
The abstract is in Adobe Acrobat PDF format, which means you will need Acrobat Reader software on your computer. If you do not have it, you may download it FREE from the Adobe Web site,
http://www.adobe.com/products/acrobat/readstep.html
STEP 4: After reviewing the abstract, you may join the voting list or decline to join by clicking the “Back” button at the top left corner of the screen and choosing “yes” or “no” on the TCC Ballot Response page. Please remember to indicate your classification.
NOTE: The interest classifications have recently been expanded. Previously, there were only three interest classifications (user, producer, general interest), but there are now seven (user/consumer, manufacturer/producer, general interest, contractor, consultant, government/military, and research, development, and testing). Please consider these classifications carefully.
Be sure to click on the SUBMIT RESPONSE button at the bottom of the page to submit your response.
After you have submitted your response, the TCC Response Confirmation page will appear stating that your response has been recorded. In addition, you will receive an e-mail confirmation of your response.
------------------------------------------------------------------------
Thank you for your participation in the online process of forming a voting list.
Roy Bash comments
Richard:
The committee’s second reference under “Criteria for Steel and Cast Iron” by S.P. Ewing is considered to be a classic in literature pertaining to valid research projects for field testing CP criteria.
Dr. Ewing explains that all potentials were measured by interrupting the CP current so that the open circuit (instant-off) potential would be free of IR drop. The reference electrode was always placed on the surface of the soil directly above the buried steel pipe specimen being tested.
On page 415 of Dr. Ewing’s paper covering the test results of his field research project at the four locations in Oklahoma in 1948, outlines what he considered to be the most significant findings of his research as follows:
“The most significant findings of the test will be discussed first .The data obtained indicate that corrosion was stopped in each environment at a specific open circuit potential . These potential values varied about 0.1 volt between the different environments. They were 0.05 to 0.15 volt less (more cathodic) than the usually accepted value of -0.85 volt as measured with reference to the copper/copper sulfate electrode.”
From the above Dr. Ewing found that the open circuit (instant-off) potential criterion for CP of steel ranges from -0.70 to -0.80 volt, CSE. Please note that he considered this to be “the most significant finding of the test.
The committee lists this scientifically sound article as their second reference, supposedly in support of their position that the instant-off potential criterion for CP of steel is -850 mV, CSE.
Listing a scientifically sound article as a reference and then ignoring or outright disputing it leaves a lot to be desired concerning the best professional approach for addressing any issue being debated
The-700 to -800mV, CSE instant-off potential CP criterion for steel can easily be supported by use of long standing basic scientific principles from the textbooks. Conversely, the -850 mV, CSE instant-off potential CP criterion for steel can easily be proven to be at least -50 mV, CSE overly stringent.
As A. W. Peabody wrote in his original book, the maximum potential, CSE that can be expected on a buried
steel pipeline in natural soils and waters is –0.8 volt. This is a scientific fact that is as true today as it was when Peabody wrote it. Quoting from the second edition of the A.W. Peabody book on page 69, “Newly laid , coated steel pipelines may have an average potential in the range of -0.5 to -0.7 V, whereas old , bare steel lines may have an average potential more in the range of -0.1 to 0.3 V (CSE)”.
There just can not be any justification for NACE to produce a standards document based on buried steel pipelines reaching potentials even near -0.8 volt, CSE. In 56 years of CP practice this writer has measured only four potentials above -700 mV ,CSE on buried steel pipelines (-705mV, -706mV, -718mV, and -725mV) and all of these were on the same coated steel pipeline in 200 to 250 ohm-cm tropical rainforest soil in Suriname, South America.
Some members of the committee have noted that steel reaches a potential of 0.8 volt ,CSE or more in high pH alkaline environments, but as Peabody has written in his book, steel does not corrode in high pH environments.
Quoting Peabody from page 43 of his book, “When steel is immersed in a sufficiently caustic solution (around pH 11 and higher) it can be made to discharge current without appreciable metal loss”.
All aspects of an overly stringent CP criterion for steel are negative.
1, It offers no more assurance of corrosion control than an adequate CP criterion.
2. It increases the risk of causing corrosion damage on nearby buried or submerged metallic structures
3.It increases the risk of damaging coatings on coated pipelines.
4.It increases the risk of hydrogen damage to the steel being protected.
5. It unnecessarily increases the cost of CP.
6.It would overtly enrich (monetarily) the CP industry and NACE.
Respectfully Submitted,
L.A. (Roy) Bash, P.E.
L.A. (Roy) Bash
Global Cathodic Protection, Inc.
A CerAnode Company
P.O. Box 571507
Houston, TX 77257
5826 Schumacher Lane
The committee’s second reference under “Criteria for Steel and Cast Iron” by S.P. Ewing is considered to be a classic in literature pertaining to valid research projects for field testing CP criteria.
Dr. Ewing explains that all potentials were measured by interrupting the CP current so that the open circuit (instant-off) potential would be free of IR drop. The reference electrode was always placed on the surface of the soil directly above the buried steel pipe specimen being tested.
On page 415 of Dr. Ewing’s paper covering the test results of his field research project at the four locations in Oklahoma in 1948, outlines what he considered to be the most significant findings of his research as follows:
“The most significant findings of the test will be discussed first .The data obtained indicate that corrosion was stopped in each environment at a specific open circuit potential . These potential values varied about 0.1 volt between the different environments. They were 0.05 to 0.15 volt less (more cathodic) than the usually accepted value of -0.85 volt as measured with reference to the copper/copper sulfate electrode.”
From the above Dr. Ewing found that the open circuit (instant-off) potential criterion for CP of steel ranges from -0.70 to -0.80 volt, CSE. Please note that he considered this to be “the most significant finding of the test.
The committee lists this scientifically sound article as their second reference, supposedly in support of their position that the instant-off potential criterion for CP of steel is -850 mV, CSE.
Listing a scientifically sound article as a reference and then ignoring or outright disputing it leaves a lot to be desired concerning the best professional approach for addressing any issue being debated
The-700 to -800mV, CSE instant-off potential CP criterion for steel can easily be supported by use of long standing basic scientific principles from the textbooks. Conversely, the -850 mV, CSE instant-off potential CP criterion for steel can easily be proven to be at least -50 mV, CSE overly stringent.
As A. W. Peabody wrote in his original book, the maximum potential, CSE that can be expected on a buried
steel pipeline in natural soils and waters is –0.8 volt. This is a scientific fact that is as true today as it was when Peabody wrote it. Quoting from the second edition of the A.W. Peabody book on page 69, “Newly laid , coated steel pipelines may have an average potential in the range of -0.5 to -0.7 V, whereas old , bare steel lines may have an average potential more in the range of -0.1 to 0.3 V (CSE)”.
There just can not be any justification for NACE to produce a standards document based on buried steel pipelines reaching potentials even near -0.8 volt, CSE. In 56 years of CP practice this writer has measured only four potentials above -700 mV ,CSE on buried steel pipelines (-705mV, -706mV, -718mV, and -725mV) and all of these were on the same coated steel pipeline in 200 to 250 ohm-cm tropical rainforest soil in Suriname, South America.
Some members of the committee have noted that steel reaches a potential of 0.8 volt ,CSE or more in high pH alkaline environments, but as Peabody has written in his book, steel does not corrode in high pH environments.
Quoting Peabody from page 43 of his book, “When steel is immersed in a sufficiently caustic solution (around pH 11 and higher) it can be made to discharge current without appreciable metal loss”.
All aspects of an overly stringent CP criterion for steel are negative.
1, It offers no more assurance of corrosion control than an adequate CP criterion.
2. It increases the risk of causing corrosion damage on nearby buried or submerged metallic structures
3.It increases the risk of damaging coatings on coated pipelines.
4.It increases the risk of hydrogen damage to the steel being protected.
5. It unnecessarily increases the cost of CP.
6.It would overtly enrich (monetarily) the CP industry and NACE.
Respectfully Submitted,
L.A. (Roy) Bash, P.E.
L.A. (Roy) Bash
Global Cathodic Protection, Inc.
A CerAnode Company
P.O. Box 571507
Houston, TX 77257
5826 Schumacher Lane
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