DNV GL, the technical advisor to the oil and gas industry has introduced a new methodology designed to address the major safety threat and multi-billion-dollar cost posed by corrosion under insulation (CUI), according to a statement by the company.

The company elaborated that the Recommended Practice (RP) DNVGL­-RP­-G109 was developed in collaboration with several regulatory bodies, international oil and gas operators and major players in the supply chain to deliver a practical and cost-effective methodology.

DNV said that CUI can take the form of localized external corrosion in carbon and low-alloy steels, external stress corrosion cracking (ESCC) or pitting in austenitic and duplex stainless steel.

Koheila Molazemi, Technology and Innovation Director, DNV GL – Oil and Gas said that “Corrosion under insulation is recognized as the single most expensive corrosion issue in the oil and gas and petrochemical industries. Our Recommended Practice has been developed as a guide to the most effective and efficient way to assess, mitigate and systematically manage the risk.”

“The new Recommended Practice is a great example of DNV GL’s approach to exploring and identifying problems with our partners, to ultimately establish industry benchmarks for safely and effectively manage these issues.”, she added.

Additionally, DNV GL has developed a digital tool to support the implementation and use of its methodology. CUI Manager applies machine learning to CUI data gathered from operators with the methodology from DNV GL’s Recommended Practice, to continuously assess and calculate the risk of CUI in process plants.