What is Cathodic Protection? Galvanic & Sacrificial


Definition - What does Galvanic Cathodic Protection (Galvanic CP) mean?

Galvanic cathodic protection (CP) is a cathodic protection technique to control the corrosion of metal when using a galvanic anode as a sacrificial metal in an electrochemical cell. This is achieved by placing the metal to be protected in contact with another, more easily corroded metal to act as the anode of the electrochemical cell.

A galvanic cathodic protection system may be used on reinforced concrete structures and metallic structures exposed to aggressive agents. Common applications are:

  • Steel pipelines and storage tanks
  • Ship hulls
  • Offshore oil platforms and onshore oil well casings
  • Metal reinforcement bars in concrete
  • Galvanized steel

Cathodic protection is feasible when the surfaces to be protected are buried or submerged. The anodes in sacrificial anode cathodic protection systems must be periodically inspected and replaced when consumed.