5. SHIP HULLS

Due to the environment in which they operate, ships are among the structures most exposed to environmental corrosion. The sea water is a very corrosive environment because the salt present in it makes it a very good conductor of electricity. It creates a lot of free ions which accelerate oxidation of iron (mild steel) which ships are made of. This oxidation creates what we know as rust.

Almost every part of the ship is subjected to corrosion, with varying intensity. Parts of the vessel underwater or exposed to water (e.g. ballast tanks and pipes) are more affected by corrosion.

There are various methods of protecting the ship hull and other areas from corrosion. The selected method depends on the area to be protected, its shape and its environment.

There are three major methods of corrosion protection.

• Anti-corrosion paints – metallic/organic

• Cathodic Protection – ICCP (Impressed Current Cathodic Protection)

• Cathodic Protection – Sacrificial Anodes