Active cathodic protection of steel structures in river and sea water

Corrosion of metals and structures in river and sea water is one of great economic and technical problems in shipbuilding; moreover, it affects vessel combat readiness a lot. This paper describes the fundamentals of electrochemical corrosion as well as protection procedures. An up-to-date corrosion protection by means of electrical current is explained in particular as well as some examples of successfully realized cases in our country, relating to both river and sea water. Although there are certain specific moments in the application of this type of protection - mainly concerning the required current density of 0.3 mAm-2 for river water and 20 mAm-2 for sea water - the results show that this system works successfully in both cases.