Pipeline cladding, pipeline lining, valves or other pipeline fittings can present the coupling of two or
more different metals. This represents a risk of galvanic corrosion when an electrochemical cell is setup,
generating preferential corrosion of one metal over another. In a worst case scenario, this may lead
to pipeline failure with associated environmental risks, shut down periods, loss in production and
ultimately costs. Commercially available corrosion inhibitors have been applied for many years with
success and there are numerous electrochemical techniques and test protocols to help select the “right”
corrosion inhibitor for the particular application. The effectiveness of different corrosion inhibitors with
specific metals has been studied and proven in the past; however the effect of corrosion inhibitors on
galvanic couples can still be considered a new subject. This paper describes the laboratory work
performed to test the inhibition of galvanic corrosion using different formulations and commercially
available products. The results have shown simple electrochemical techniques and common equipment
can be used to obtain meaningful and relevant data. Although additional research can be performed on
the subject, the results confirm that the selection of the right corrosion inhibitor is fundamental to the
integrity of a galvanic couple.
Keywords: galvanic, corrosion, inhibitors, laboratory testing