The Proposed Electric Circuit Diagram Of The Buried Bare Pipe Segment- Soil - Earth System With And Without Applying Cathodic Protection System

Ashraf Ahmed
2010 The International Conference on Electrical Engineering  
Based on proposed electrical concept of corrosion process, it is possible to simulate buried bare pipe segment with the surrounding soil medium by an electric circuit where the circuit electric quantities are function of the electrochemical properties of the soil as 4 th degree polynomial equations. The equivalent cylindrical electrolytic capacitor between the pipe and the remote earth and the potential across it, verifies the equation that charge Q = C × V at natural condition with & without
more » ... on with & without applying cathodic protection system. The created positive charges consists with an equivalent negative charge (electrons losses) a charged stray electrolytic capacitor between the pipe and the earth through thin film soil layer around the pipe as cylindrical capacitor. The amounts of these charges are depending on the electrochemical properties of the soil which are surrounding the pipe segment, the length of the pipe segment and its diameter. The rate of discharge (equivalent to capacitor self discharge) is to be considered as the corrosion current. That's beside the facts deduced before that all electrical parameters prints & equations are function of the electrochemical properties of soil medium around the pipe at different cathodic protection levels. The error of these new equations of the electrical parameters reduced to be less than ± 5%. This will help to study both the corrosion problem and cathodic protection for a complete pipeline by an electric concept with an electric analogue circuit which is the aim of this study. This will help, in the future, in the choice of pipeline route, pipeline cathodic protection design and cathodic protection maintenance process for the pipe line along its route, however long it is.
doi:10.21608/iceeng.2010.33273 fatcat:4quxqm5fyfbkhlbsbhluyqo3zu