Cathodic protection snapshot

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!

https://corrospective.com/courses/basics-of-cathodic-protection-cp-in-oil-and-gas-industry

Practice your CP knowledge here! Check out Quiz 1!

😀Happy learning!😀

Comments

Resources for a corrosion beginner

Corrosion is a complex subject. It is difficult to pick and choose the starting point. It is very easy to spiral into a confused state of mind if the right resources are not available. Hence, I write this blog post to list out a few books which are great if you are a corrosion enthusiast. Here goes - 1. Corrosion Engineering by Mars. G Fontana I love this book and I always refer to it for my work. 2. Peabody's control of pipeline corrosion - 3. Corrosion engineering - Principles and practice - Pierre Roberge The website www.corrosion-doctors.org has a more extensive list of corrosion articles. Other than that, there are online corrosion magazines which you can access - 1. Materials performance - www.materialsperformance.com 2. corrosionpedia.com 3. CORROSION journal meridian.allenpress.com/corrosion - it has a few open access articles. Check out these resources as a starting point!

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