O.W. Davenport, Exxon Co.
One of the principal causes of subsurface failures is corrosion. Corrosivity of well fluids is primarily related to hydrogen sulfide and/or carbon dioxide gases in the produced water. Optimum utilization of corrosive-resistant materials for component parts of sucker rod pumps has been the more economical practice in Exxon's operation as compared with the use of corrosion inhibitors and less expensive metals. Past performance of pump part metals was studied to provide guidelines in upgrading the pump part metallurgy. Using a computerized data bank, over 8,000 pump runs were analyzed from 26 major folds within the West Texas and Oklahoma areas, most of which contained hydrogen sulfide in the produced fluid. General guidelines for pump part metals selection were established. The study indicated that average pump part service of at least I2 months should be expected with proper metallurgy selection.