Evaluation of a commercial inhibitor efficiency for corrosion protection of galvanic coupling between alloys commonly used in the oil & gas industry

The efficiency and the persistency of a commercial inhibitor, produced by Beaumont Italia S.p.a., was evaluated for the corrosion protection of galvanic coupling between the API 5L X65 carbon steel and Inconel 625 alloy, both of them being widely used in the oil and gas industry. A CO2 saturated, 5% NaCl solution simulated the aggressive environment, while the mixed corrosion potential and the coupling current were monitored by means of the electrochemical noise technique (EN). Results pointed out a protection persistency of about 7 days; further measurements led to similar responses to the non-inhibited control case.