Press Release

DNV GL introduces new recommended practice and digital tool to manage major safety and cost risks exposed by corrosion under insulation

DNV GL, March 23, 2020
  • Corrosion under insulation (CUI) is a major safety challenge and the single most expensive corrosion issue in the oil & gas and petrochemical industries
  • DNV GL’s industry-first methodology helps to identify the areas of a plant with the greatest current and future risk, and take action to prevent failures
  • CUI Manager, a new digital tool, combines DNV GL’s methodology with live asset data. It provides detailed insights on CUI risks, potential mitigation measures and cost.

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

CUI, a type of corrosion which arises when water becomes trapped between insulation and the piping and vessels it is designed to protect, has contributed to more than 20% of all major oil and gas accidents in the EU alone over the past 35 years. DNV GL’s industry-first methodology helps integrity engineers and plant managers to identify the areas of a plant with the greatest current and future risk of CUI and take action to prevent failures.

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 for managing the threat of CUI and is setting a new standard for managing CUI risk.

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. Despite the risks that CUI exposes, the oil and gas industry has never adopted a standard approach for identifying and managing the threat. Operators currently employ a variety of methods to identify the presence of CUI on their assets. These range from using diverse inspection methods that can lead to undetected defects to the expensive process of systematically removing and renewing all insulation and coating with limited upfront assessment of the risk of CUI presence. DNV GL’s RP provides a systematic approach to assessing, mitigating and updating CUI risk.

Koheila Molazemi, Technology and Innovation Director, DNV GL - Oil & Gas said: “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.

“With its hidden and pervasive threat to life, property and the environment, and the cost of accidents and mitigation being staggeringly high - the combination of the new Recommended Practice and the CUI Manager, the digital tool enables the industry to control CUI risk significantly more cost-efficiently.

“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.”

DNV GL has also 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. According to estimations, the tool can reduce the cost of CUI-related maintenance by up to 50%, while enabling asset managers to:

  • Continuously assess CUI risk and predict the cost of mitigation
  • Optimize CUI strategies and gain detailed insights
  • Access a global database, gain knowledge and benchmark performance
  • Track the status of inspections and manage deviations
  • Evaluate the risk impact of different mitigation measures and their cost
  • Communicate and interpret data more effectively
  • Integrate CUI assessment data with existing ERP systems.

Click here to access a complimentary preview of Recommended Practice DNVGL­-RP­-G109

Click here for more information on the CUI manager

About DNV GL
DNV GL is the independent expert in risk management and quality assurance, operating in more than 100 countries. Through its broad experience and deep expertise, DNV GL advances safety and sustainable performance, sets industry benchmarks, and inspires and invents solutions.

Whether assessing a new ship design, optimizing the performance of a wind farm, analyzing sensor data from a gas pipeline or certifying a food company’s supply chain, DNV GL enables its customers and their stakeholders to make critical decisions with confidence.

Driven by its purpose, to safeguard life, property, and the environment, DNV GL helps tackle the challenges and global transformations facing its customers and the world today and is a trusted voice for many of the world’s most successful and forward-thinking companies.

As the technical advisor to the oil and gas industry, we bring a broader view to complex business and technology risks in global and local markets. Providing a neutral ground for industry cooperation, we create and share knowledge with our customers, setting standards for technology development and implementation. From project initiation to decommissioning, our independent experts enable companies to make the right choices.

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