Evaluation of preferential weld corrosion susceptibility and its mitigation in slightly sour conditions

2015 by Nace International. Preferential Weld Corrosion (PWC) susceptibility was studied in slightly sour wet gas piping system using electrochemical methods based on the "hockey puck" technique. A benchmark testing environment was simulated under the operating conditions and was used to evaluate the performance of several corrosion inhibitors for in suppressing PWC in static conditions. The results showed that under the testing conditions the Heat Affected Zones (HAZ) from the welds were susceptible to PWC. Also pitting occurs across all the components of the weld, independently of the relative cathode/anode relationship. Profilometry assessment of the specimen after exposure supported the findings from the electrochemical measurements. The tested corrosion inhibitors dosed at 100 ppm concentration in static conditions showed reduction of PWC and pitting severity.

Evaluation of preferential weld corrosion susceptibility and its mitigation in slightly sour conditions Conference Paper