Corrosion under insulation: a rewiew

Abstract

Corrosion under insulation (CUI) occurs from electrochemical reactions on the surface of thermally insulated industrial equipment and has water as an electrolyte. CUI generates many costs for companies due to maintenance and can also cause problems to human and environmental integrity. In this work, vast bibliographic research was carried out on corrosion under insulation, in articles published between 1998 and 2022, with the objective of evaluating the CUI in Industry, factors that influence it, corrosion mechanism, non-destructive inspection techniques and techniques that can work as a mitigation for this problem. As a result, it was confirmed that corrosion under insulation is a serious problem for the industry, especially the petrochemical one, as its detection is not so simple and is expensive when done visually. To solve this difficulty in identification and detection, non-destructive tests are used, through various technologies, it is possible to prevent the insulation from being damaged and, in some cases, the inspection can be carried out without stopping the process. In addition, serious situations can be generated due to the non-monitoring of the CUI, such as: Economic, human and environmental integrity impacts.