Corrosion under insulation (CUI) is regarded as one of the largest corrosion threats across the oil, gas and petro-chemical sectors. CUI is a condition which results in aggressive localized corrosion in carbon and low alloy steel. This form of corrosion occurs when water is absorbed by or collected in the insulation. The equipment begins to corrode as it is exposed to water and oxygen. CUI is common in refineries, process plants, midstream and downstream, where equipment operates at higher temperatures.
The Inhibitor Fusion Tape is a silicone based self-amalgamating tape that is impregnated with corrosion inhibitors that were specifically designed to combat CUI. The Tape provides a physical barrier between the steel substrate and insulation medium and can transfer corrosion inhibitor to the underlying metal surface in the event of any water ingress or sweating of the line. Finally, the Tape is translucent to allow ease of inspection and as the Tape has no glues/resins/primers for adhesion, the tape is easily removed for inspection cycles leaving no adhesive residue behind.
This paper will provide various case studies and showcase a diversified overview. The Tape has also been tested and passed ISO 19277 for protective coating systems under insulation according to modified ISO 192771
Integrity management of corrosion under insulation (CUI) has historically and continues to be one of the biggest corrosion related challenges within the oil & gas, maritime, chemical and petrochemical industries.2 Corrosion of piping, associated flanges, pressure vessels and structural components from CUI is a commonly found phenomenon and if left undetected or not stringently managed can result in catastrophic leaks or explosions, equipment failure and periods of prolonged downtime due to repair or replacement. It is estimated around 40% to 60% of an operator's pipeline maintenance budget is a result of CUI.3
Methods to try and control CUI risks have been to adopt conventional coatings such as epoxies, thermal sprayed aluminum (TSA) etc., along with a robust insulation system, such as conventional rock wool with metal cladding or newer technologies such as open or closed cell insulation, as well as UV cured glass reinforced plastic (GRP) or glass fiber reinforced plastic (GFRP).2,3