Cathodic Protection:

Cathodic protection (CP) is a method of corrosion control that can be applied to buried and submerged metallic structures.

It is normally used in conjunction with coatings and can be considered as a secondary corrosion control technique. The primary corrosion control method on any given structure is normally a coating system which can be between 50 and 99 % efficient depending upon age, type, method of installation, etc.

Corrosion Control

Cathodic Protection is an electrochemical means of corrosion control in which the oxidation reaction in a galvanic cell is concentrated at the anode and suppresses corrosion of the cathode in the same cell. Figure 1 shows a simple cathodic protection system. The steel pipeline is cathodically protected by its connection to a sacrificial magnesium anode buried in the same soil electrolyte.