Cathodic protection (CP) is a technique used to control the corrosion of a metal surface by making it the cathode of an electrochemical cell. A simple method of protection connects the metal to be protected to a more easily corroded "sacrificial metal" to act as the anode. The sacrificial metal then corrodes instead of the protected metal.
Cathodic protection is a popular protection method for preventing corrosion in pipelines, offshore oil platforms and other steel structures. However, to be implemented effectively, it is crucial to understand the basic principles of bimetallic/galvanic corrosion.
Therefore cathodic protection connections do not have to be as massive as grounding connections. A very low resistance system is required for a cathodic protection system, and it must remain low in resistance over the life of the system. The higher the resistance, the less efficient is the cathodic protection system.
Cathodic protection prevents corrosion by converting all of the anodic (active) sites on the metal surface to cathodic (passive) sites by supplying electrical current (or free electrons) from an alternate source. Usually this takes the form of galvanic anodes, which are more active than steel. This practice is also referred to as a sacrificial ...
Cathodic Protection Program. A critical component of corrosion mitigation, cathodic protection is an electrochemical process to control the corrosion of a metal surface by transferring the corrosion from the protected structure to a more easily corroded metal.
Cathodic Protection Illustration Pipeline CP Example. On an unprotected pipeline, there are naturally occurring potential variations. Wherever you go from a minor positive to a minor negative, there is a current flow where galvanic corrosion will occur.
In summary, cathodic protection is a commonly used method of protecting steel structures, yet can be costly and require routine maintenance and replacement. Products that provide a protective layer with zero reactivity are more likely to extend the life of steel structures and create a nonreactive layer of protection.
Corrpro has been at the forefront of cathodic protection engineering, offering total corrosion solutions to the oil & gas, petrochemical, municipal and marine markets for more than 30 years. As a subsidiary of Aegion Corporation, Corrpro strives to provide the highest quality corrosion control materials and most cost-effective services ...
Cathodic protection is a procedure used to protect an object from corrosion by making it a cathode. For example, to make a tank a cathode, an anode is attached to it. Both have to be in an electrolyte such as soil or water. Cathodic protection is also known as a cathodic protection system.
Cathodic Protection Industry. Corrosion and cathodic protection (CP) are electrochemical phenomena. Understanding corrosion and CP requires a basic knowledge of chemistry and electrochemistry. Electrochemistry is a branch of chemistry dealing with chemical changes that accompany the passage of an electric current, or a process in which a ...