On the detection and mitigation of corrosion under insulation (CUI) of mild steel

Corrosion under insulation (CUI) is a major issue impacting the petrochemical and refinery industries. Herein, the corrosion rate of mild steel under moist insulation was investigated as a function of the moisture content in the insulation (by volume %). It was observed that the corrosion rate increases with increasing moisture content. Cathodic protection (CP) using sacrificial zinc anodes was investigated as a means to mitigate CUI, with in-situ electrochemical tests being used to determine the rate of CUI and efficacy of CP.