Corrosion and steel grounding

Abstract

Based on the National Bureau of Standards statistical data on the corrosion of steel (M. Romanoff, 1957), an equation is developed to estimate the corrosion rate of underground steel that varies with soil resistivity, pH value, moisture and aeration. This formula, together with IEEE Standard 80-1986, is used in the design of steel grounding. formulae are also discussed on how to design proper cathodic protection methods to minimize corrosion of steel grounding. The typical corrosion rate of steel is 5-7 mils/year. A numerical example is discussed to enhance the understanding of steel grounding design for high voltage AC substations.<>