Improve plant maintenance programs by keeping CUI in check

Plant safety and efficiency starts with CR-Tech™ CUI defense

A technical article from ROCKWOOL Technical Insulation in the April 2025 issue of Hydrocarbon Processing highlights the advantage of using ROCKWOOL stone wool insulation with CR-Tech™ corrosion-resistant technology to combat corrosion under insulation (CUI). 

Maintenance is critical to the safe and efficient operation of refineries and petrochemical facilities. However, not all maintenance challenges are as easy to deal with as others. CUI is a particularly complex problem to detect and tackle, occurring (as the name implies) under the insulation used to keep pipelines insulated against thermal losses and excessive noise.

CUI also has dangerous and costly consequences. It reduces plant efficiency through increased heat loss and energy use; it can also lead to leaks and spills, posing a hazard to personnel, risking environmental harm, and resulting in unplanned downtime and possible regulatory action. CUI is thus one area where prevention is far easier and less costly than a cure.

Most CUI mitigation solutions focus on minimizing contact between a pipe’s metal surface and water. This is reflected in NACE Standard RP0198-2017, which states that insulation systems that hold the least water and dry most quickly produce the least amount of CUI damage.

Industry testing confirms water repellency, corrosion mitigation and durability

Authored by Technical Services Manager, Ricky Seto, and Technical and GKAM Manager - Americas, Abraham Sebastian, the article explains how insulation treated with the CR-Tech additive performed in standard industry testing, confirming its ability to provide the necessary water repellency, corrosion mitigation, and durability in real-world conditions:

• ASTM C1617-19 standard corrosion testing to assess its durability at various operating temperatures.
• ASTM G189 standard testing to document corrosion mitigation performance when exposed to a water volume equal to 15 times the annual rainfall in Houston, Texas, USA, at a 1% infiltration rate.

Ricky and Abraham conclude: “The stringent corrosion testing showed that stone wool insulation containing inhibitor provides superior water repellency and corrosion mitigation and maintains durable performance at significant simulated rainfall levels. These results suggest that this insulation effectively mitigates the effects of CUI while improving the safety of people working in refineries and petrochemical plants.”

Interested in how our CR-Tech corrosion inhibitor could improve your plant maintenance programs by keeping CUI in check? 

Check out the full article here.