Steel as Grounding Material Study of Corrosion Processes

摘要

As at present, steel is and can be used very effectively as ground grid material. Rather, the steel grounding may be supplemented by including the steel bars used in concrete foundations of equipment and the substation building. This will yield substantial savings. Typically the cross-sectional area of steel is about 4-5 times larger than that of copper, but even then use of steel over copper is much cheaper. The main concern in using steel as discussed above is the corrosion. This can be compensated partially by increasing the cross sectional area of the conductor, but the extent of increase depends on the corrosion study of the site. It is also recommended that the continuity, and the integrity of the steel ground grid, be checked and tested periodically - and more often in corrosive environment, by visual inspection at random locations to ensure proper operations and safety. Nevertheless, among other things, ever increasing pollution is immensely increasing the contaminating of the soils and is accelerating the process of corrosion of underground steel structures - including grounding electrodes. Even the overhead electrodes are being affected by the pollution.