Operation and Maintenance: Cathodic Protection Systems - index
Operation and Maintenance: Cathodic Protection Systems - ufc_3_570_060001
Unified Facilities Criteria (UFC) - ufc_3_570_060002
Foreword - ufc_3_570_060003
Contents - ufc_3_570_060004
Contents - Cont'd - ufc_3_570_060005
Contents - Cont'd - ufc_3_570_060006
Contents - Cont'd - ufc_3_570_060007
Contents - Cont'd - ufc_3_570_060008
Figures - ufc_3_570_060009
Figures - Cont'd - ufc_3_570_060010
Tables - ufc_3_570_060011
Tables - Cont'd - ufc_3_570_060012
Chapter 1 Introduction - ufc_3_570_060013
CP System Maintenance
Chapter 2 Princles of Operation
Anode/Cathode Relationship
Figure 2-1. The Corrosion Cell
Cathode Reaction
General Corrosion
Concentration Cell Corrosion
Figure 2-3. Concentration Cell Caused by Different Environments
Figure 2-4. Concentration Cell Caused by Different Concentrations of Oxygen
Figure 2-6. Concentration Cell Caused by Non-Homogeneous Soil
Figure 2-7. Concentration Cell Caused by Concrete and Soil Electrolytes
Figure 2-8. Galvanic Corrosion Cell Caused by Different Metals
Figure 2-9. Galvanic Corrosion Cell Caused by Old and New Steel
Figure 2-10. Galvanic Corrosion Cell Caused by Marred and Scratched Surfaces
Figure 2-11. Combination of Many Different Corrosion Cells at Work
Figure 2-12. Stray Current Corrosion Cell Caused by External Anode and Cathode
Table 2-1. Weight Loss of Specific Metals at a Current of One Ampere for One Year (1 Amp-Year)
Figure 2-13. Stray Current Corrosion Cell Caused by a DC Transit System
Figure 2-14. Stray Current Corrosion Cell Caused by an HVDC Transmission
Figure 2-16. Stray Current Corrosion Cell Caused by a Cathodic Protection Sytem
Resistivity of the Electrolyte
Temperature - ufc_3_570_060035
Figure 2-17. Effect of Electrolyte pH on the Rate of Corrosion
Galvanic Series
Table 2-2. Electrical Potential of Metals with Various Reference Cells
Introduction to Cayhodic Protection
Table 2-3. Current Requirements for Cathodic Protection of Bare Steel
Table 2-4. Current Requirements for Cathodic Protection of Coated Steel
Galvanic Cathodic Protection
Figure 2-18. Direct Attachment Galvanic (Sacrificial) Cathodic Protection System
Figure 2-19. Distributed Sacrificial (Galvanic) Cathodic Protection System
Table 2-5. Composition of Magnesium Anodes
Table 2-6. Compositions of Zinc Anodes
Table 2-7. Compositions of Aluminum Anodes
Table 2-8. Sacrificial Anodes Available Voltage for Cathodic Protection
Table 2-9. Estimated Output Current of Sacrificial Anodes
Table 2-10. Applicable Tables In MIL-HDBK-1004/10
Advantages and Disadvantages of Galvanic Anode Systems
Figure 2-20. Galvanic Anode Installation
Figure 2-21. Above Grade Test Station
Figure 2-22. Subsurface Test Station
Impressed Current Cathodic Protection
Figure 2-24. Impressed Current Cathodic Protection System
Rectifiers are either automatically controlled or manually controlled
Figure 2-25. Impressed Current Cathodic Protection System Rectifier
Table 2-11. Electrochemical Equivalents Of Common Structural Metals
Table 2-12. Cast Iron Composition
Table 2-13. Cast Iron Anodes
Graphite Anodes - ufc_3_570_060062
Aluminum Anodes
Ceramic and Mixed-Metal Oxide Anodes
Polymer Conductive Anodes
Table 2-14. Applicable Tables In MIL-HDBK-1004/10
Vertical Remote Impressed Current CP Systems
Figure 2-27. Horizontal Remote Impressed Current Cathodic Protection System
Figure 2-28. Distributed Impressed Current Cathodic Protection System
Advantages and Disadvantages of Impressed Current Anode Systems
Figure 2-30. Flush Test Station
Figure 2-31. Abovegrade Test Station
Chapter 3 Requirements
Systems Requiring Cathodic Protection
Field Tests
Chapter 4 Scheduled Preventive Maintenances
Table 4-1. Close-Interval Survey CP System Component Testing Requirements
Table 4-2. Close-Interval Survey Potential Measurement Locations
Corrosion Survey
Table 4-3. Corrosion Survey Component Testing
Table 4-4. Corrosion Survey Potential Measurements
Table 4-4. Corrosion Survey Potential Measurements (Continued)
Water Tank Calibration
Table 4-5. Water Tank Calibration CP System Component Tests
Rectifier Operational Inspection
Table 4-7. Recommended Over-the-Anode Intervals
Galvanic Anode Check
Resistance Bond Check
Leak Survey
Table 4-8. Recommended Corrective Actions for Preventing Leaks
Record Keeping Requirements
Chapter 5 Unscheduled Maintenance Requirements
Figure 5-1. Troubleshooting Block Diagram
Normal DC voltage
Figure 5-2. Typical Rectifier Wiring Diagram
Figure 5-3. Shunt Multiplication Factors
Half the normal current output
Anode Lead Wires
Voltage Near Zero
Diodes
Rectifier Taps
Rectifier Input Voltage
Table 5-1. Common Impressed Current Rectifier Problems
Common Problems
Interference Corrosion Control
Figure 5-4. Correction of Interference by Resistive Bonding
Figure 5-5. Bonding For Continuity
Figure 5-7. Use of Coating Cathode to Control Interference
Figure 5-8. Use of Isolation on Foreign Structure to Control Interference
Figure 5-9. Use of a Combination of Mitigation Techniques to Control Interference
Chapter 6 Inspection Procedures and Criteria
Criteria - ufc_3_570_060112
Special Conditions
Other Considerations - ufc_3_570_060114
Alternative Refereneces Electrodes
Alternative Metallic Material or Structure
Chapter 7 Testing
Figure 7-1. Copper/Copper Sulfate Reference Electrode (Half-Cell)
IR Drop Error
Figure 7-2. IR Drop Error
Figure 7-3. Anode Gradient Error
Figure 7-4. Contact Resistance Error
Figure 7-5. Mixed Potential Error
Impressed Current Cathodic Protection System
Figure 7-6. Single Electrode Potential Survey
Test Methods for the -0.85 ON Criterion
Test Methods for the -0.85 Instant-OFF Criterion
Types of Interrupters
Manually Synchronizable Interrupter
Figure 7-7. Typical Displayed Readings Using Digital Voltmeter
Figure 7-8. Readings Recorded by Digital Voltmeter with Minimum/Maximum Function
Figure 7-9. Examples of Voltage Spiking on Instant-OFF Readings
Structure -To-Soil Potential Limits
Water Storage Tanks
Table 7-1. Potential Limits for Underground Coated Structures
Figure 7-10. Positive Reading for Cell-To-Cell Survey
Figure 7-11. Negative Reading for Cell-To-Cell Survey
Figure 7-12. Rectifier Efficiency
Figure 7-13. Testing for a Shorted Dielectric
Testing for a Shorted Dielectric
Figure 7-14. Testing an Installed Dielectric with the Insulated Flange Tester
Figure 7-15. Testing for a Shorted Dielectric Using a Pipe Locator
Figure 7-16. Testing for a Shorted Dielectric with Power Supply
Figure 7-17. Typical Casing Installation
Figure 7-18 Testing for a Shorted Casing
Figure 7-19. Testing for a Shorted Casing with Power Supply
Testing for a Short Between Two Structures
Figure 7-20. Testing For A Short Between Two Structures
Figure 7-21. Testing for a Short Between Two Structures with Power Supply
Figure 7-22. Testing for a Short Between Two Structures
Table 7-2. Expected Potential Example Under Shorted/Not Shorted Conditions
Figure 7-23. Testing for a Short Between Two Structures
If the two potential measurements are not significantly different
Figure 7-24. Testing for a Short Between Two Structures with Power Supply
Existing Metallic Structures
Connections
Figure 7-25. Removing Temporary Anodes (Ground Rods)
Figure 7-26. Soil Resistivity by the Four Pin Method (Wenner)
Table 7-3. Four-Pin Soil Resistivity Measurement Reading Multipliers
Figure 7-28. Soil Resistivity Measurement Using a Soil Rod
Figure 7-29. Soil Resistivity Measurement Using a Soil Box
Figure 7-30. Effect of pH on the Corrosion Rate of Steel
Figure 7-31. Antimony Electrode
Figure 7-32. pH Measurement with Electrolyte Current Flow
Figure 7-33. Typical IR Drop Test Span Installation
Figure 7-34. Calibration of an IR Drop Test Span
Direction of Current Flow
Figure 7-35. IR Drop Test Span, Direction Of Current Flow
Table 7-4. Estimated Resistance of Steel Pipelines
Figure 7-36. Null Ammeter Method, Using the Multi-Combination Meter
Interference Testing Procedures
Interference from Cathodic Protection Rectifiers
Figure 7-37. Cell-To-Cell Polarity on Foreign Structure
Figure 7-38. Normal and Abnormal Potentials of Protected
Interference from Variable (Fluctuating) Sources
Another method of finding these points is through current measurements
Appendix A Part 1
Overall Procedures
Conduct an annual cathodic protection performance survey
Updating the cathodic protection program
Engineering Construction Management
Potable water systems and treatment corrosion control craftsman will
Cooling water systems and treatment corrosion control craftsman will
Protective coating corrosion control is by Service Contract
Record Procedures
Failure Records
Operational Logs
Summary of Changes
Appendix A Part 2 Instructions for Completing air Force Form 491
Location Reference Drawing Number
Care must be taken to read the correct polarity
Figure A2-1A Sample Completed AF Form 491
Figure A2-1B Sample Completed AF Form 491
Appendix A Part 3 Instructions for Completing air Form 1686
Date Installed
Figure A3-1A Sample Completed AF Form 1686
Figure A3-1B Sample Completed AF Form 1686
Appendix A Part 4 Instructions for Completing air Force Form 1687
Appendix A Part 4 Instructions for Completing air Force Form 1687 - Cont'd - ufc_3_570_060199
Appendix A Part 4 Instructions for Completing air Force Form 1687 - Cont'd - ufc_3_570_060200
Figure A4-1A Sample Completed AF Form 1687
Figure A4-1B Sample Completed AF Form 1687
Appendix A Part 5 Sample Completed air Force Form 1688
Appendix A Part 6
Appendix A Part 7 Guidelines for Preparing the Cathodic Protection Annual Performance Booklet
Appendix A Part 7 Guidelines for Preparing the Cathodic Protection Annual Performance Booklet - cont'd
Appendix A Part 8 References (Air Force)
Additional References - ufc_3_570_060208
Education and Training Available
Education and Training Available - Cont'd - ufc_3_570_060210
Education and Training Available - Cont'd - ufc_3_570_060211
Appendix B Naval Shore Facilities Corrosion Control Program
Corrosion Control - ufc_3_570_060213
NAVFACENGCOM Headquarters
Corrosion Control References
Figure B-1 Cathodic Protection Installation Report
Figure B-2 Cathodic Protection Quarterly Structure-to-Electrode Potential Report
Figure B-3 Cathodic Protection Rectifier Report
Appendix C Reserved for Future Army Use
Appendix D General References
Operation and Maintenance: Cathodic Protection Systems - ufc_3_570_060001
Unified Facilities Criteria (UFC) - ufc_3_570_060002
Foreword - ufc_3_570_060003
Contents - ufc_3_570_060004
Contents - Cont'd - ufc_3_570_060005
Contents - Cont'd - ufc_3_570_060006
Contents - Cont'd - ufc_3_570_060007
Contents - Cont'd - ufc_3_570_060008
Figures - ufc_3_570_060009
Figures - Cont'd - ufc_3_570_060010
Tables - ufc_3_570_060011
Tables - Cont'd - ufc_3_570_060012
Chapter 1 Introduction - ufc_3_570_060013
CP System Maintenance
Chapter 2 Princles of Operation
Anode/Cathode Relationship
Figure 2-1. The Corrosion Cell
Cathode Reaction
General Corrosion
Concentration Cell Corrosion
Figure 2-3. Concentration Cell Caused by Different Environments
Figure 2-4. Concentration Cell Caused by Different Concentrations of Oxygen
Figure 2-6. Concentration Cell Caused by Non-Homogeneous Soil
Figure 2-7. Concentration Cell Caused by Concrete and Soil Electrolytes
Figure 2-8. Galvanic Corrosion Cell Caused by Different Metals
Figure 2-9. Galvanic Corrosion Cell Caused by Old and New Steel
Figure 2-10. Galvanic Corrosion Cell Caused by Marred and Scratched Surfaces
Figure 2-11. Combination of Many Different Corrosion Cells at Work
Figure 2-12. Stray Current Corrosion Cell Caused by External Anode and Cathode
Table 2-1. Weight Loss of Specific Metals at a Current of One Ampere for One Year (1 Amp-Year)
Figure 2-13. Stray Current Corrosion Cell Caused by a DC Transit System
Figure 2-14. Stray Current Corrosion Cell Caused by an HVDC Transmission
Figure 2-16. Stray Current Corrosion Cell Caused by a Cathodic Protection Sytem
Resistivity of the Electrolyte
Temperature - ufc_3_570_060035
Figure 2-17. Effect of Electrolyte pH on the Rate of Corrosion
Galvanic Series
Table 2-2. Electrical Potential of Metals with Various Reference Cells
Introduction to Cayhodic Protection
Table 2-3. Current Requirements for Cathodic Protection of Bare Steel
Table 2-4. Current Requirements for Cathodic Protection of Coated Steel
Galvanic Cathodic Protection
Figure 2-18. Direct Attachment Galvanic (Sacrificial) Cathodic Protection System
Figure 2-19. Distributed Sacrificial (Galvanic) Cathodic Protection System
Table 2-5. Composition of Magnesium Anodes
Table 2-6. Compositions of Zinc Anodes
Table 2-7. Compositions of Aluminum Anodes
Table 2-8. Sacrificial Anodes Available Voltage for Cathodic Protection
Table 2-9. Estimated Output Current of Sacrificial Anodes
Table 2-10. Applicable Tables In MIL-HDBK-1004/10
Advantages and Disadvantages of Galvanic Anode Systems
Figure 2-20. Galvanic Anode Installation
Figure 2-21. Above Grade Test Station
Figure 2-22. Subsurface Test Station
Impressed Current Cathodic Protection
Figure 2-24. Impressed Current Cathodic Protection System
Rectifiers are either automatically controlled or manually controlled
Figure 2-25. Impressed Current Cathodic Protection System Rectifier
Table 2-11. Electrochemical Equivalents Of Common Structural Metals
Table 2-12. Cast Iron Composition
Table 2-13. Cast Iron Anodes
Graphite Anodes - ufc_3_570_060062
Aluminum Anodes
Ceramic and Mixed-Metal Oxide Anodes
Polymer Conductive Anodes
Table 2-14. Applicable Tables In MIL-HDBK-1004/10
Vertical Remote Impressed Current CP Systems
Figure 2-27. Horizontal Remote Impressed Current Cathodic Protection System
Figure 2-28. Distributed Impressed Current Cathodic Protection System
Advantages and Disadvantages of Impressed Current Anode Systems
Figure 2-30. Flush Test Station
Figure 2-31. Abovegrade Test Station
Chapter 3 Requirements
Systems Requiring Cathodic Protection
Field Tests
Chapter 4 Scheduled Preventive Maintenances
Table 4-1. Close-Interval Survey CP System Component Testing Requirements
Table 4-2. Close-Interval Survey Potential Measurement Locations
Corrosion Survey
Table 4-3. Corrosion Survey Component Testing
Table 4-4. Corrosion Survey Potential Measurements
Table 4-4. Corrosion Survey Potential Measurements (Continued)
Water Tank Calibration
Table 4-5. Water Tank Calibration CP System Component Tests
Rectifier Operational Inspection
Table 4-7. Recommended Over-the-Anode Intervals
Galvanic Anode Check
Resistance Bond Check
Leak Survey
Table 4-8. Recommended Corrective Actions for Preventing Leaks
Record Keeping Requirements
Chapter 5 Unscheduled Maintenance Requirements
Figure 5-1. Troubleshooting Block Diagram
Normal DC voltage
Figure 5-2. Typical Rectifier Wiring Diagram
Figure 5-3. Shunt Multiplication Factors
Half the normal current output
Anode Lead Wires
Voltage Near Zero
Diodes
Rectifier Taps
Rectifier Input Voltage
Table 5-1. Common Impressed Current Rectifier Problems
Common Problems
Interference Corrosion Control
Figure 5-4. Correction of Interference by Resistive Bonding
Figure 5-5. Bonding For Continuity
Figure 5-7. Use of Coating Cathode to Control Interference
Figure 5-8. Use of Isolation on Foreign Structure to Control Interference
Figure 5-9. Use of a Combination of Mitigation Techniques to Control Interference
Chapter 6 Inspection Procedures and Criteria
Criteria - ufc_3_570_060112
Special Conditions
Other Considerations - ufc_3_570_060114
Alternative Refereneces Electrodes
Alternative Metallic Material or Structure
Chapter 7 Testing
Figure 7-1. Copper/Copper Sulfate Reference Electrode (Half-Cell)
IR Drop Error
Figure 7-2. IR Drop Error
Figure 7-3. Anode Gradient Error
Figure 7-4. Contact Resistance Error
Figure 7-5. Mixed Potential Error
Impressed Current Cathodic Protection System
Figure 7-6. Single Electrode Potential Survey
Test Methods for the -0.85 ON Criterion
Test Methods for the -0.85 Instant-OFF Criterion
Types of Interrupters
Manually Synchronizable Interrupter
Figure 7-7. Typical Displayed Readings Using Digital Voltmeter
Figure 7-8. Readings Recorded by Digital Voltmeter with Minimum/Maximum Function
Figure 7-9. Examples of Voltage Spiking on Instant-OFF Readings
Structure -To-Soil Potential Limits
Water Storage Tanks
Table 7-1. Potential Limits for Underground Coated Structures
Figure 7-10. Positive Reading for Cell-To-Cell Survey
Figure 7-11. Negative Reading for Cell-To-Cell Survey
Figure 7-12. Rectifier Efficiency
Figure 7-13. Testing for a Shorted Dielectric
Testing for a Shorted Dielectric
Figure 7-14. Testing an Installed Dielectric with the Insulated Flange Tester
Figure 7-15. Testing for a Shorted Dielectric Using a Pipe Locator
Figure 7-16. Testing for a Shorted Dielectric with Power Supply
Figure 7-17. Typical Casing Installation
Figure 7-18 Testing for a Shorted Casing
Figure 7-19. Testing for a Shorted Casing with Power Supply
Testing for a Short Between Two Structures
Figure 7-20. Testing For A Short Between Two Structures
Figure 7-21. Testing for a Short Between Two Structures with Power Supply
Figure 7-22. Testing for a Short Between Two Structures
Table 7-2. Expected Potential Example Under Shorted/Not Shorted Conditions
Figure 7-23. Testing for a Short Between Two Structures
If the two potential measurements are not significantly different
Figure 7-24. Testing for a Short Between Two Structures with Power Supply
Existing Metallic Structures
Connections
Figure 7-25. Removing Temporary Anodes (Ground Rods)
Figure 7-26. Soil Resistivity by the Four Pin Method (Wenner)
Table 7-3. Four-Pin Soil Resistivity Measurement Reading Multipliers
Figure 7-28. Soil Resistivity Measurement Using a Soil Rod
Figure 7-29. Soil Resistivity Measurement Using a Soil Box
Figure 7-30. Effect of pH on the Corrosion Rate of Steel
Figure 7-31. Antimony Electrode
Figure 7-32. pH Measurement with Electrolyte Current Flow
Figure 7-33. Typical IR Drop Test Span Installation
Figure 7-34. Calibration of an IR Drop Test Span
Direction of Current Flow
Figure 7-35. IR Drop Test Span, Direction Of Current Flow
Table 7-4. Estimated Resistance of Steel Pipelines
Figure 7-36. Null Ammeter Method, Using the Multi-Combination Meter
Interference Testing Procedures
Interference from Cathodic Protection Rectifiers
Figure 7-37. Cell-To-Cell Polarity on Foreign Structure
Figure 7-38. Normal and Abnormal Potentials of Protected
Interference from Variable (Fluctuating) Sources
Another method of finding these points is through current measurements
Appendix A Part 1
Overall Procedures
Conduct an annual cathodic protection performance survey
Updating the cathodic protection program
Engineering Construction Management
Potable water systems and treatment corrosion control craftsman will
Cooling water systems and treatment corrosion control craftsman will
Protective coating corrosion control is by Service Contract
Record Procedures
Failure Records
Operational Logs
Summary of Changes
Appendix A Part 2 Instructions for Completing air Force Form 491
Location Reference Drawing Number
Care must be taken to read the correct polarity
Figure A2-1A Sample Completed AF Form 491
Figure A2-1B Sample Completed AF Form 491
Appendix A Part 3 Instructions for Completing air Form 1686
Date Installed
Figure A3-1A Sample Completed AF Form 1686
Figure A3-1B Sample Completed AF Form 1686
Appendix A Part 4 Instructions for Completing air Force Form 1687
Appendix A Part 4 Instructions for Completing air Force Form 1687 - Cont'd - ufc_3_570_060199
Appendix A Part 4 Instructions for Completing air Force Form 1687 - Cont'd - ufc_3_570_060200
Figure A4-1A Sample Completed AF Form 1687
Figure A4-1B Sample Completed AF Form 1687
Appendix A Part 5 Sample Completed air Force Form 1688
Appendix A Part 6
Appendix A Part 7 Guidelines for Preparing the Cathodic Protection Annual Performance Booklet
Appendix A Part 7 Guidelines for Preparing the Cathodic Protection Annual Performance Booklet - cont'd
Appendix A Part 8 References (Air Force)
Additional References - ufc_3_570_060208
Education and Training Available
Education and Training Available - Cont'd - ufc_3_570_060210
Education and Training Available - Cont'd - ufc_3_570_060211
Appendix B Naval Shore Facilities Corrosion Control Program
Corrosion Control - ufc_3_570_060213
NAVFACENGCOM Headquarters
Corrosion Control References
Figure B-1 Cathodic Protection Installation Report
Figure B-2 Cathodic Protection Quarterly Structure-to-Electrode Potential Report
Figure B-3 Cathodic Protection Rectifier Report
Appendix C Reserved for Future Army Use
Appendix D General References
