Corrosion under Insulation (CUI) in Oil and Gas Industries

Offshore oil and gas sector generally acknowledges corrosion as a significant safety concern. To reduce the danger of corrosion-related failures at processing facilities, which are significant sources of risk to onshore and offshore oil and gas installations, we do adequate corrosion monitoring and inspection. Companies around the globe are very much concern to avoid the catastrophic failures due to corrosion. In this category, corrosion under insulation (CUI) is one of the most grievous types of corrosion but still concealed. This also has inspection challenges; therefore, currently it has major impact on countries’ economy. Both downstream and upstream sectors have become aware of this issue, and the difficulties due to CUI are present. Therefore, the requirements for risk-based evaluation and thorough inspection plans are imposed over the past few decades. It has been found that the major causes of CUI are the use of open-cell insulation materials, degradation of joints and joint sealants, and inadequate maintenance of metal cladding. The threat of CUI can be specifically prevented with the help of coordination between operations and inspection and maintenance departments. In this chapter, the focus is on different monitoring techniques for CUI and some insulating materials such as glass wool, mineral wool, and rockwool, including their service temperatures. This chapter also includes the research done till date and present the knowledge gaps and future research to understand and organize the CUI.