|MadSci Network: Engineering|
Dear Mr. Anuar; This is a topic which would require several chapters in a text on corrosion. Too long for me to present here. Also, this is a specialty in the field of corrosion. I will list several sources for information on this matter.  www.nace.org This is the site for the major society for corrosion engineering. They will list commercial organizations specializing in this. Their Journal "Materials Performance" [MP] always has a section on this topic.  In the April 2000 issue of "MP" there is an article on exactly your problem. "Cathodic Protection criteria and its Application to Mature Pipelines" Ask for a copy of this article from: Jeff Didas Columbia Gas Transmission Co., 1700 MacCorkle Drive, SE, Charleston, West Virginia 25314 USA  www.tinker-rasor.com or email them at: firstname.lastname@example.org "Tinker-Rasor"is a large firm specializing in corrosion protection. They may have literature or brochures of use to you - and some products also, of course.  www.loresco.com is another useful site. Please contact me if I can be of further assistance. Charlie A. Crutchfield
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