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Cathodic protection snapshot

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Name of technique

Cathodic protection


Use

  • Prevent corrosion
  • Complement protection given by coatings

Definition

  • A technique where an ionic current towards the structure from the electrolyte is used to counter the corrosion current flowing out of the structure.

CP criteria

  • CP potential of -850 mV vs. CSE
  • An instant off potential of at least -850 mV vs CSE
  • A minimum 100 mV polarization post instant off

CP measurement techniques

  • Soil resistivity
  • CIPS
  • DCVG
  • Line current

Factors affecting CP requirements

  • pH
  • velocity
  • ionic type
  • ionic concentration
  • temperature

Issues with CP

  • Stray current corrosion
  • Insufficient CP potential
  • Insufficient CP current
  • Electrical shorting

I will discuss all these with examples in this major course, where you can prepare for the basics for your certification course!


Check out the introductory video for the brand new course and click on the link to access!





Practice your CP knowledge here! Check out Quiz 1!


😀Happy learning!😀


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