OPERATION AND MAINTENANCE: CATHODIC PROTECTION
OPERATION AND MAINTENANCE: CATHODIC PROTECTION - continued
FOREWORD - UFC3-570-060003
CONTENTS - UFC3-570-060004
CONTENTS - continued - UFC3-570-060005
CONTENTS - continued - UFC3-570-060006
CONTENTS - continued - UFC3-570-060007
CONTENTS - continued - UFC3-570-060008
CONTENTS - continued - UFC3-570-060009
CONTENTS - continued - UFC3-570-060010
CONTENTS - continued - UFC3-570-060011
CONTENTS - continued - UFC3-570-060012
Chapter 1. INTRODUCTION - UFC3-570-060013
Benefits - UFC3-570-060014
Chapter 2. PRINCIPLES OF OPERATION
Anode/Cathode Relationship
Figure 2-1. The Corrosion Cell
Cathode Reaction
Types of Corrosion
Concentration Cell Corrosion - UFC3-570-060020
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
Dissimilar 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
Resistivity of the Electrolyte
Temperature - UFC3-570-060035
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 Cathodic 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
Aluminum Anodes - UFC3-570-060047
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
Impressed Current Rectifiers
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 - UFC3-570-060062
Aluminum Anodes - UFC3-570-060063
Ceramic and Mixed-Metal Oxide Anodes
Ceramic and Mixed-Metal Oxide Anodes - continued
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
Metallic Ferrous Pipe
New Piping Systems
Chapter 4. SCHEDULED PREVENTIVE MAINTENANCE
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
Impressed Current Anode Bed
Maintenance Intervals
Procedure - UFC3-570-060088
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
TROUBLESHOOTING GALVANIC (SACRIFICIAL) CATHODIC PROTECTION SYSTEMS
INTERFERENCE CORROSION CONTROL
Continuity
Figure 5-5. Bonding For Continuity
Additional Coating
Installation of Nonmetallic Sections or Isolations
Figure 5-9. Use of a Combination of Mitigation Techniques to Control Interference
Chapter 6. INSPECTION PROCEDURES AND CRITERIA
CRITERIA - UFC3-570-060112
Special Conditions
Aluminum Piping
Sound Engineering Practices
Alternative Metallic Material or Structure
Chapter 7. TESTING
Initiation of a Reference Electrode
Initiation of a Reference Electrode - continued
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
Test Methods for the -0.85 ON Criterion
Test Methods for the -0.85 ON Criterion - continued
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 (Reference Cell to Meter Negative, Structure to Meter Positive)
Figure 7-9. Examples of Voltage Spiking on Instant-OFF Readings
Using a High Speed Data Logger and a Filtered Oscilloscope
Water Storage Tanks
Uncoated Structures
Accuracy
Figure 7-11. Negative Reading for Cell-To-Cell Survey
Figure 7-12. Rectifier Efficiency
Testing for a Shorted Dielectric
Testing for a Shorted Dielectric - continued
Using a Radio Frequency 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 a Casing Without Cathodic Protection on the Carrier Pipeline.
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 with Cathodic Protection on Both Structures
Table 7-2. Expected Potential Example Under Shorted/Not Shorted Conditions
Figure 7-23. Testing for a Short Between Two Structures without Cathodic Protection on Either Structure
Testing for a Short Between Two Structures Without Cathodic Protection on Either Structure
Figure 7-24. Testing for a Short Between Two Structures with Power Supply
Existing Metallic Structures
Connections
More than One Anode Bed
Four-Pin Method
Table 7-3. Four-Pin Soil Resistivity Measurement Reading Multipliers
Figure 7-27. Two-Pin Method ("Shepard's Canes") of Soil Resistivity Measurement
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
Measurement Circuits
Figure 7-35. IR Drop Test Span, Direction Of Current Flow
Table 7-4. Estimated Resistance of Steel Pipelines
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 and Foreign Pipelines Potential Survey of Pipelines for Interference
Interference from Variable (Fluctuating) Sources
Interference from Variable (Fluctuating) Sources - continued
Appendix A - Part 1. SAMPLE BASE CORROSION CONTROL OPERATING INSTRUCTION (AIR FORCE)
Overall Procedures
Overall Procedures - continued - UFC3-570-060179
Overall Procedures - continued
Overall Procedures - continued - UFC3-570-060181
Overall Procedures - continued - UFC3-570-060182
Overall Procedures - continued - UFC3-570-060183
Overall Procedures - continued - UFC3-570-060184
Overall Procedures - continued - UFC3-570-060185
Failure Records
Operational Logs
Summary of Changes
Appendix A. Part 2. INSTRUCTIONS FOR COMPLETING AIR FORCE FORM 491
Ground Bed Data
Operating Record - UFC3-570-060191
Figure A2-1A
Figure A2-1B. SAMPLE COMPLETED AF FORM 491
Appendix A. Part 3. INSTRUCTIONS FOR COMPLETING AIR FORCE FORM 1686
Operating Record - UFC3-570-060195
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 - continued
SECOND PAGE (CORROSION ENGINEER DIRECTS)
Figure A4-1A. SAMPLE COMPLETED AF FORM 1687
Figure A4-1B. SAMPLE COMPLETED AF FORM 1687
Figure A5-1. SAMPLE COMPLETED AF FORM 1688
Figure A6. SAMPLE COMPLETED AF FORM 1689
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 - continued
Appendix A - Part 8. REFERENCES (AIR FORCE)
ADDITIONAL REFERENCES
EDUCATION AND TRAINING AVAILABLE
EDUCATION AND TRAINING AVAILABLE - continued - UFC3-570-060210
EDUCATION AND TRAINING AVAILABLE - continued - UFC3-570-060211
Appendix B. NAVAL SHORE FACILITIES CORROSION CONTROL PROGRAM
Corrosion Control - UFC3-570-060213
NAVFACENGCOM Headquarters.
Corrosion Control References
CATHODIC PROTECTION INSTALLATION REPORT
Figure B-2. CATHODIC PROTECTION QUARTERLY STRUCTURE-TO-ELECTRODE POTENTIAL REPORT
Figure B-3. CATHODIC PROTECTION RECTIFIER REPORT
Appendix C.
Appendix D. GENERAL REFERENCES
UFC3-570-06
OPERATION AND MAINTENANCE: CATHODIC PROTECTION - continued
FOREWORD - UFC3-570-060003
CONTENTS - UFC3-570-060004
CONTENTS - continued - UFC3-570-060005
CONTENTS - continued - UFC3-570-060006
CONTENTS - continued - UFC3-570-060007
CONTENTS - continued - UFC3-570-060008
CONTENTS - continued - UFC3-570-060009
CONTENTS - continued - UFC3-570-060010
CONTENTS - continued - UFC3-570-060011
CONTENTS - continued - UFC3-570-060012
Chapter 1. INTRODUCTION - UFC3-570-060013
Benefits - UFC3-570-060014
Chapter 2. PRINCIPLES OF OPERATION
Anode/Cathode Relationship
Figure 2-1. The Corrosion Cell
Cathode Reaction
Types of Corrosion
Concentration Cell Corrosion - UFC3-570-060020
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
Dissimilar 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
Resistivity of the Electrolyte
Temperature - UFC3-570-060035
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 Cathodic 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
Aluminum Anodes - UFC3-570-060047
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
Impressed Current Rectifiers
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 - UFC3-570-060062
Aluminum Anodes - UFC3-570-060063
Ceramic and Mixed-Metal Oxide Anodes
Ceramic and Mixed-Metal Oxide Anodes - continued
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
Metallic Ferrous Pipe
New Piping Systems
Chapter 4. SCHEDULED PREVENTIVE MAINTENANCE
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
Impressed Current Anode Bed
Maintenance Intervals
Procedure - UFC3-570-060088
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
TROUBLESHOOTING GALVANIC (SACRIFICIAL) CATHODIC PROTECTION SYSTEMS
INTERFERENCE CORROSION CONTROL
Continuity
Figure 5-5. Bonding For Continuity
Additional Coating
Installation of Nonmetallic Sections or Isolations
Figure 5-9. Use of a Combination of Mitigation Techniques to Control Interference
Chapter 6. INSPECTION PROCEDURES AND CRITERIA
CRITERIA - UFC3-570-060112
Special Conditions
Aluminum Piping
Sound Engineering Practices
Alternative Metallic Material or Structure
Chapter 7. TESTING
Initiation of a Reference Electrode
Initiation of a Reference Electrode - continued
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
Test Methods for the -0.85 ON Criterion
Test Methods for the -0.85 ON Criterion - continued
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 (Reference Cell to Meter Negative, Structure to Meter Positive)
Figure 7-9. Examples of Voltage Spiking on Instant-OFF Readings
Using a High Speed Data Logger and a Filtered Oscilloscope
Water Storage Tanks
Uncoated Structures
Accuracy
Figure 7-11. Negative Reading for Cell-To-Cell Survey
Figure 7-12. Rectifier Efficiency
Testing for a Shorted Dielectric
Testing for a Shorted Dielectric - continued
Using a Radio Frequency 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 a Casing Without Cathodic Protection on the Carrier Pipeline.
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 with Cathodic Protection on Both Structures
Table 7-2. Expected Potential Example Under Shorted/Not Shorted Conditions
Figure 7-23. Testing for a Short Between Two Structures without Cathodic Protection on Either Structure
Testing for a Short Between Two Structures Without Cathodic Protection on Either Structure
Figure 7-24. Testing for a Short Between Two Structures with Power Supply
Existing Metallic Structures
Connections
More than One Anode Bed
Four-Pin Method
Table 7-3. Four-Pin Soil Resistivity Measurement Reading Multipliers
Figure 7-27. Two-Pin Method ("Shepard's Canes") of Soil Resistivity Measurement
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
Measurement Circuits
Figure 7-35. IR Drop Test Span, Direction Of Current Flow
Table 7-4. Estimated Resistance of Steel Pipelines
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 and Foreign Pipelines Potential Survey of Pipelines for Interference
Interference from Variable (Fluctuating) Sources
Interference from Variable (Fluctuating) Sources - continued
Appendix A - Part 1. SAMPLE BASE CORROSION CONTROL OPERATING INSTRUCTION (AIR FORCE)
Overall Procedures
Overall Procedures - continued - UFC3-570-060179
Overall Procedures - continued
Overall Procedures - continued - UFC3-570-060181
Overall Procedures - continued - UFC3-570-060182
Overall Procedures - continued - UFC3-570-060183
Overall Procedures - continued - UFC3-570-060184
Overall Procedures - continued - UFC3-570-060185
Failure Records
Operational Logs
Summary of Changes
Appendix A. Part 2. INSTRUCTIONS FOR COMPLETING AIR FORCE FORM 491
Ground Bed Data
Operating Record - UFC3-570-060191
Figure A2-1A
Figure A2-1B. SAMPLE COMPLETED AF FORM 491
Appendix A. Part 3. INSTRUCTIONS FOR COMPLETING AIR FORCE FORM 1686
Operating Record - UFC3-570-060195
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 - continued
SECOND PAGE (CORROSION ENGINEER DIRECTS)
Figure A4-1A. SAMPLE COMPLETED AF FORM 1687
Figure A4-1B. SAMPLE COMPLETED AF FORM 1687
Figure A5-1. SAMPLE COMPLETED AF FORM 1688
Figure A6. SAMPLE COMPLETED AF FORM 1689
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 - continued
Appendix A - Part 8. REFERENCES (AIR FORCE)
ADDITIONAL REFERENCES
EDUCATION AND TRAINING AVAILABLE
EDUCATION AND TRAINING AVAILABLE - continued - UFC3-570-060210
EDUCATION AND TRAINING AVAILABLE - continued - UFC3-570-060211
Appendix B. NAVAL SHORE FACILITIES CORROSION CONTROL PROGRAM
Corrosion Control - UFC3-570-060213
NAVFACENGCOM Headquarters.
Corrosion Control References
CATHODIC PROTECTION INSTALLATION REPORT
Figure B-2. CATHODIC PROTECTION QUARTERLY STRUCTURE-TO-ELECTRODE POTENTIAL REPORT
Figure B-3. CATHODIC PROTECTION RECTIFIER REPORT
Appendix C.
Appendix D. GENERAL REFERENCES
UFC3-570-06
