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cathodic protection

cathodic protection by impressed current
Cathodic protection by impressed current
Credit: Northern Arizona Wind & Sun

Cathodic protection is a method of preventing oxidation (rusting) of exposed metal structures, such as bridges and pipelines, by imposing between the structure and the ground a small electrical voltage that opposes the flow of electrons and that is greater than the voltage present during oxidation.

A common form of cathodic protection is known as impressed current. With this technique a current is impressed between the buried structure and an anode. This forces a reversal of the current, and causes the anode to be consumed rather than the pipe.

Related category

   • sacrificial anode

Related category