Study on Cathodic Protection Principles and Requirements of Underground Steel Pipes (Concept and Laboratory/model Scale)

The objective of this project is to study the cathodic protection principle and
requirements of underground steel pipes by using concept and laboratory
experiments.
Cathodic protection (CP) is a means of preventing a metallic object which is either
buried in the ground or immersed under water from corrosion. It is basically an
electro-chemical process. In understanding CP, basic knowledge about several
subjects, chemistry, electricity, metallurgy and mathematics will be required. The
basic principal of CP is to turn a metals surface into a cathode (cathodic), hence
the name cathodic protection. A metals surface, buried or immersed, can contain
anodic and cathodic areas, corrosion only occurs at the anodic areas, therefore if a
metal objects surface can be turned into a cathode over its entire surface, then
corrosion can be prevented on the metallic structure. Corrosion is not actually
eliminated; it is moved to a known location by adding an anode which is designed
to slowly corrode in a controlled manner, thus leaving the intended metallic
structure intact.
In order to achieve the objectives, project planning using Gantt chart has been
developed. It started with Literature Study mainly on the underlying theories of
cathodic protection principles. Experiment will then be conducted to:
1. Test severalpossible sacrificial anodes and select the most suitable one.
2. Test the efficiency of cathodic protection on buried steel pipe using the
chosen alloy as the sacrificial anode. The result will then be compared to
the buried steel pipe without cathodic protection (in terms of corrosion
rate).
Cathodic protection is a promising corrosion inhibitor with the advantages such as
cut maintenance expense, cut replacement costs, decrease laborcosts, stop rust and
corrosion, less expensive than coatings, and easy to install.