In India, several thousands kilometres of steel pipelines are in use for transportation of oil, gas and water. Corrosion is an electrochemical process which occurs in mild steel structures buried underground or immersed in water (Seawater). The difference in potential between the Anodic and Cathodic parts present in the underground or submerged steel structure sets up a flow of galvanic current between these parts.  This results in loss of +ve ions & cause corrosion. The potential difference between the anodic and cathodic areas activates/initiates the flow of corrosion current in steel structures in the presence of a conductive environment like soil or sea water.

The transmission and distribution companies take extensive safety and precautionary steps to prevent leaks and damages by implementing active corrosion control programs. By adopting effective corrosion control measures, millions of rupees worth of valuable products are saved.

Cathodic Protection is the most effective technique to prevent the electrochemical corrosion in underground pipelines. In this system, the corrosion current flowing during the galvanic corrosion process is countered by imposing an external DC current for neutralizing the corrosion current.