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

Corrosion quiz - 6

Corrosion quiz - 6 Loading… Done? Click here for the previous and next ! Check out the isocorrosion charts here ! https://corrospective.com/ 😀Happy learning! 😀

Corrosion risk planning - 2 - Above ground storage tanks - oil and gas- PART 1

Above ground storage tanks 1. Inner walls Coating degradation Corrosion due to water/dissolved oxygen insufficient/damaged cathodic protection system dissolved sacrificial anodes 2. Outer walls/roof Atmospheric corrosion coating degradation due to moisture + UV radiation + temperature Erosion and wear due to wind and dust particles biological growth at the bottom areas near soil soil corrosion near the bottom 3. Pipes Atmospheric corrosion Coating degradation mechanical failure internal corrosion due to water/dissolved oxygen crevice corrosion in areas facing away from atmosphere corrosion at welds and joints microbial corrosion at 6 o' clock positions erosion corrosion at bends 4. Railing Coating degradation Wrong coating selection based on pure aesthetics coating damage at joints and bends corrosion at welds in the railing crevice corrosion at fixtures pitting corrosion 5. Breather valve uniform corrosion/pitting depending on whether it is made up of carbon steel/stainless steel...

Types of MARINE corrosion

Types of MARINE corrosion The marine environment is one of the most corrosive environments. Its corrosivity is due to the ionic concentration of the seas and oceans, temperature variations, wind velocities, depth of the sea, and biological elements. As a result, the corrosion on marine structures such as ships, FPSO, and offshore platforms, appears in multiple forms. Hence, it is important to learn about the basic types of corrosion as applicable to the marine environment. Some of these types of corrosion in a marine environment are - Uniform corrosion due to sodium, magnesium, and calcium salts Uniform corrosion is characterized by the removal of the material all over the surface. It leads to thinning of the walls. Pitting in active-passive alloys such as aluminium Active-passive alloys have a thin oxide film on the surface. A small break due to the chlorides in the seawater allows the penetration of the water and ions, leading to pit formation. Crevice corrosion in fixtures and ...

Search This Blog