ON FORECASTING CARBON-DIOXIDE CORROSION OF CARBON-STEELS UNDER CONDITIONS OF SALT DEPOSIT FORMATION

Current techniques for forecasting carbon dioxide corrosion of steels are considered. Estimates based on these techniques are shown to differ from the corrosion data for the real pipelines of the oil-collecting system (OCS) of the Samotlor oil field. A forecasting scheme is proposed taking into account the dependence of the steel corrosion rate on the formation of mineral salt deposits on the corroded surface. The rate of local carbon dioxide corrosion under conditions of salt deposit formation is evaluated on the basis of histograms of the corrosion rate distribution for steel specimens exposed in the OCS pipelines. A good coincidence of the forecast with the actual corrosion rate is reported.