Electrochemical determination of the minimum cathodic protection potential and underground steel corrosion rate. On the moderate criteria for the protection efficiency

Experimentally are determined the minimum protection potential Emin and steel corrosion rate in a number of soils by means of calculation using the cathode polarization curve. Their correlation is shown with results of weight tests in conditions of the free corrosion and cathode polarization. It is shown too that Emin is not connected directly with the steel free corrosion rate but when lowering Emin normally is decreased. Using Emin as a characteristic for the soil corrosion effect and features of the cathode protection when softening the criteria of its efficiency are discussed. 21 refs., 4 figs., 2 tabs