TABLE OF CONTENTS Chapter 1-Principles and Definitions A. Electrolysis in General: 1. Electrolysis 2. Electrolyte, Electrode, Anode, and Cathode. 3. Amount of Chemical Action... Page 15 15 15 16 16 ló 16 16 9. 10. 11. 12. 17 Self-Corrosion 17 Acceleration of Local or Self-Corrosion.. 13. Anodic and Self-Corrosion.. 17 17 17 17. Alternating or Frequently Reversed Direct Currents.. 18. Action on Underground Metallic Structures... 19. Electrolysis Mitigation 20. Electrolysis Survey 21. Overall Potential Measurements. 22. Potential Gradient 23. Potential Difference 24. Arithmetical Average 25. Algebraic Average 27. Drainage System 28. Uninsulated Track Feeder System. 18 18 18 19 19 19 19 19 20 20 20 29. Insulated Negative Feeder System. 888 20 20 20 Chapter 2-Design, Construction, Operation and Maintenance 1. Measures Tending Both to Railway Economy and the Reduction of Stray Current.... 2. Measures Employed Solely for Electrolysis Prevention..... (b) Applicable to Affected Structures. (c) Interconnection of Affected Structures and Railway Return Circuit. Page I. RAILWAYS. A. Features Which Affect Electrolysis Conditions. 1. (a) Importance of Rail Circuit.. (b) Rail Bond Resistance and Tests.. (c) Types of Bonds.. Soldered Bonds Brazed or Welded Bonds. Resistance Weld Electric Arc Process. Oxy-Acetylene Process Pin Expanded Terminal Bonds. Compressed Terminal Bonds.. (c) Relation of Feeding Distance to Stray Currents and Overall Voltages ... 34 (d) Economic Considerations Involved in Additional Supply Stations (e) Automatic Substations (f) Location of Supply Stations... (g) Alternating Current Systems. 5. for Electrolysis Mitigation. Interconnection of Tracks.... B. Features of Railway Construction and Operation Employed (b) Insulation of Trolley Sections.. (d) Difficulties and Limitations.. 3. Reversed Polarity Trolley System.. 4. Periodic Reversal of Trolley Polarity.. AFFECTED STRUCTURES AND RAILWAY RE- A. Electrical Drainage of Cable and Pipe Systems.. 2. Avoidance of Contact with Pipes and Other Structures... 85 A. Purpose and Scope of Electrolysis Surveys. 1. Purpose of Electrolysis Surveys..... (a) Purpose of Measurement of Potential Differences.. 93 (a) Purpose of Measuring Feeder and Rail Currents.... 95 (b) Procedure in Measuring Current in Feeders and Rails 05 3. Measurement of Currents in Pipes and Cable Sheaths..... 95 Use of a Direct-Current Ratio Relay. 4. Comparing Currents Under Different Conditions.. 5. Measurement of Current Flowing from Underground (d) Testing of Cross-bonds and Special Work.. (b) Differential Method of Measuring Roadbed Resistance 102 (c) Isolation Method of Measuring Roadbed Resistance. 104 3. Location and Testing of High Resistance Joints in Pipes.. 106 4. Tracing the Source of Stray Currents..... 5. Location of Unknown Metallic Structures or Connections. 107 |