Hempel Introduces New Coating for Corrosion Under Insulation

With short overcoating intervals and a wide temperature resistance, Hempaprime CUI 275 is designed to increase productivity and improve corrosion protection at energy generation and oil and gas facilities. Photo courtesy of Hempel.

Coating solutions company Hempel (Lyngby, Denmark) recently introduced Hempaprime CUI 275 as a new coating to combat corrosion under insulation (CUI) problems.

With extremely short overcoating intervals and a wide temperature resistance, Hempaprime CUI 275 is designed to increase productivity and improve corrosion protection at energy generation and oil and gas facilities.

According to the company, CUI is often a major challenge for equipment operators in the process industries. In the United States alone, repair and downtime caused by CUI is estimated to cost the industry around $300 billion, annually.

CUI can occur when insulated pipework and other equipment is exposed to high temperatures and temperature fluctuations. As the corrosion is hidden beneath insulation, it is difficult to detect, and it can cause extensive damage before it is spotted. As a result, repair work can be expensive, requiring long shutdown periods for a plant. This is a significant problem in downstream oil and gas refineries, where CUI accounts for approximately 10% of the maintenance budget, Hempel explains.

As a leading supplier to process industries for over 50 years, Hempel offers a broad range of coatings for high heat and insulated environments. As such, Hempaprime CUI 275 is the latest addition to its portfolio, and it offers a number of potential benefits to asset owners and applicators.

During tests, the coating shown significantly higher crack resistance at high temperatures than traditional epoxy phenolic coatings, according to the company. In turn, this reduces the risk of cracking and premature failure during service. It is also extremely fast-drying, which raises applicator productivity.

“Insulated pipework and equipment can be exposed to temperature fluctuations and harsh wet/dry cycling, which makes specifying for CUI service challenging,” says Zechariah Lim, product manager for the CUI, high heat, and insulation segment. “Hempaprime CUI 275 is suitable for use in a wide range of temperatures from cryogenic up to 275 °C and has excellent crack resistance under cycling. This makes specification simpler and ensures a more reliable performance in service.”

“Importantly, Hempaprime CUI 275 also has a very short overcoating interval—just 90 minutes at 20 °C,” he adds. “As a result, applicators can coat more sections in one shift, increasing productivity in fabrication situations and reducing the time needed to re-insulate equipment during maintenance work. This can lead to significant cost savings for customers.”

According to the company, Hempaprime CUI 275 meets the ISO 19277: 2018 standard for categories CUI-1, CUI-2, CUI-3, and all cryogenic equivalents. The coating is available globally as a standard part of Hempel’s coating portfolio for process industries, including oil and gas and power generation.

Technical Coating Features

As a fast-drying, alkylamine-cured epoxy paint, Hempaprime CUI 275 provides long-lasting barrier protection in severe corrosive environments, as well as for high temperatures and wet conditions beneath thermal insulation.

According to the manufacturer, benefits of this coating include:

  • A short overcoating interval of 90 minutes at 20 °C (68 °F), which increases productivity during application
  • Wide temperature resistance from cryogenic up to 275 °C (527 °F), which simplifies specification
  • Excellent crack resistance compared to traditional epoxy phenolic coatings
  • A wide application temperature range, down to -10 °C (14 °F), which reduces heating costs during in-shop application and extends the maintenance season in cold climates
  • Can be applied on hot surfaces up to 204 °C (399 °F) to minimize disruptions and shutdowns during maintenance 

Source: Hempel, www.hempel.com.