Paper: Cathodic Protection of Oil Field Lease Equipment

Corrosion of steel, in contact with the earth, or brine, results from the creation of anodic and cathodic areas caused by differences in the electrolyte, and/or differences in the surface of the metal occurring in manufacture or fabrication. In the anodic areas current leaves the surface of the structure and enters the electrolyte, causing loss of metal or pitting action. In the cathodic areas, current flows from the electrolyte onto the surface of the structure and no corrosion occurs.