Galvanic Corrosion Challenges from Oxygen in Oil and Gas Drilling

Bottom hole assembly, located at the drill string’s lowest segment, comprises various components made from different metallic alloys joined at multiple connections. Galvanic corrosion between dissimilar metals during drilling is a concern as it impacts equipment reliability and lifespan. This study examines oxygen’s role in galvanic corrosion of Cr-Mo (chromium-molybdenum) low-alloy steel coupled with Cr-Mn-N (chromium-manganese-nickel) austenitic stainless steel and Be-Cu (beryllium-copper) alloy in simulated drilling environments. Results1 show negligible corrosion under oxygen-free conditions, but significant effects in oxygen presence due to enhanced cathodic reactions. Flow accelerates corrosion via mass transfer, though its impact is limited in the absence of oxygen.