Types of structures to be protected - internal surfaces in contact with liquid

Cathodic protection applies inside surfaces containing electrolytic conductive liquids (generally aqueous solutions). It can be, for example, water-heater, sea water ballasts or tankers cisterns, separators, storage tanks, water tanks of heat exchangers, etc 

These surfaces are very often protected also by an internal coating. The aim of cathodic protection is to prevent any attack of the defects (scratches, pores...).