EFFECT OF METALLURGICAL VARIABLES ON CORROSION OF SUCKER RODS IN BRINE CONTAINING CO2 AND H2S

Corrosion fatigue performance of several low alloy steels is compared with the performance of plain carbon steel in a salt water-CO//2-H//2S environment. The alloy steels, in general, showed lower corrosion fatigue performance than the carbon steels. Metallurgical variables such as decarbonized surface layer and other surface imperfections can reduce the corrosion fatigue life by 60%. Increasing the tensile strength of the carbon and low alloy steels above 100,000 psi did not improve their corrosion fatigue strength in H//2S system. Surface conditioning such as shot peening appeared to be the best method of improving the corrosion fatigue performance.