DNV GL unveiled a methodology for managing safety and cost associated with corrosion under insulation (CUI) alongside new technology designed to support it. CUI occurs when water becomes trapped between insulation and the piping and vessels it is designed to protect.
CUI contributed to more than 20% of all major oil and gas accidents in the EU over the past 35 years, according to DNV, in the form of localized external corrosion in carbon and low-alloy steels, external stress corrosion cracking, or pitting in austenitic and duplex stainless steel.
Recommended Practice (RP) DNVGLRPG109, was developed with several regulatory bodies, international oil and gas operators, and others in the supply chain. DNV said the methodology helps integrity engineers and plant managers identify areas with the greatest current and future risk of CUI and take action to prevent failures.
The digital tool, CUI Manager, applies machine learning to CUI data gathered from operators with the RP to assess and calculate risk of CUI in process plants.
It allows continuous assessment of CUI risk and predicts the cost of mitigation, provides access to a global database, and tracks the status of inspections and manages deviations. It also allows the evaluation of the risk impact of different mitigation measures and their cost, and integration of CUI assessment data with existing enterprise resource planning systems.
DNV estimated the tool may cut CUI-related maintenance cost by up to 50%.