Failure/degradation coated cathodes

A ballast tank filled with seawater is easily corroded. Corrosion protection by the paint on the metal surface inside the tank, which improves the insulation for the corrosion current, is conducted. The paint has problems with age-related degradation and incipient failure. To protect from the corrosion caused by these problems, plural sacrificial anodes are usually installed in the tank. When seawater is loaded in the tank, the surface of the inside tank becomes cathode and the protective potential works, because of the anode effects. The worse the coating condition becomes, the worse the insulation of the paint becomes and the lower the surface resistance becomes. Therefore, there is the possibility that the coating condition can be evaluated with the monitoring of the surface resistance. 

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