Cathodic Corrosion Protection: Inspection and Monitoring

External corrosion of subsurface metallic objects such as pipelines, storage tank bottoms, sea going vessels, jetties and piers, is not a strange phenomena to those who are particularly involved in the oil and gas industries, marine installations, power plants and fertilizer plants etc., the list can go on and on.

Corrosion involves an electrochemical reaction between metal and its environment and occurs as electricity flows off of a pipe and into the ground. This flow will take some metal with it, and a leak can eventually develop. Increasing the wall thickness of pipe to allow for corrosion will not increase a pipe’s service life because corrosion is not uniform but is concentrated at local areas. However, installation and maintenance techniques have been developed to protect metal pipe from corrosion for many years.

Much can be done to reduce the rate of corrosion of old pipe, but it may not be economical to protect it completely. The goal of corrosion prevention work is to control the flow of electricity. This is achieved by cathodic protection systems such as galvanic and impressed current, pipe coatings, and electrical isolation from other underground metallic structures or casings.

The effectiveness of cathodic protection in controlling corrosion is well recognized through out the world. Corrosion handbooks, textbooks and manuals have been written on this subject by well-known authors and researchers. Continuing research is ongoing and as a result new materials and techniques are being made available by institutions such as N.A.C.E. in their technical publications.

Any Corrosion Protection provided through Cathodic Protection Technology shall be regularly inspected and monitored to assure it provides intended corrosion protection to the structures.

This course gives basic ideas for various aspects of Cathodic Protection Systems inspection and monitoring requirements. This covers basics of corrosion, cathodic protection systems and its types, various instruments and how it shall be used, methods, safety and troubleshooting fundamentals.