Conclusions

• CatPro, a user-friendly software system for the calculation of cathodic protection (CP) problems containing underground pipelines was presented in this paper. The macroscopic model behind this software system is based on the assumption that the soil is an homogeneous three-dimensional half-space in which the pipes are laid.
• The major aspects of the program are that it considers the ohmic voltage drop in the pipes and that aboveground structures like rail bars, power stations, electric train or tram vehicles with overhead wires are integrated. As a result, the software program gives the potential level along a pipe, the potential distribution in the soil, the axial currents flowing through the pipes as well as the radial current densities leaving or entering the pipe walls.
• This software is versatile enough to deal with most of the cathodic protection problems encountered in reality. It has also been shown that it can deal with anodic, cathodic, combined and induced interference problems.
• In addition, the software system can take into account stray currents coming from other CP installations, earthing systems and others. A complex situation where overhead systems of railways are involved was investigated and it was found that the numerical calculations predicted by the program are confirmed by qualitative observations.

Study and Evaluation of Stray Current Influences on Cathodic Protection Systems of Buried Pipelines, L. Bortels, ELSYCA - Kranenberg 6 - 1731 - BELGIUM, ELSYCA