CUI-Mitigation Coating Application

HEAT-FLEX® CUI-Mitigation Coatings

Designed to Withstand Harsh Conditions Before and During Service

On average, 60 percent of all insulation in service for more than 10 years will contain corrosion-inducing moisture, which will result in corrosion under insulation​ (CUI). In fact, studies show that organic protective coatings in CUI service last from a range of 5 to 13 years.

Traditional CUI coatings fail prematurely under insulation as they have limitations handling the service and pre-service environments.  In the service environment, water, alkali, chlorides, and elevated temperatures lead to highly corrosive environments while improper coating thickness may lead to insufficient barrier protection or cracking.  In the pre-service environment, shipping, handling, construction, and exposure to highly corrosive environments can prematurely deteriorate a coating.

With that in mind, Sherwin-Williams Protective & Marine has developed a product range to best mitigate the dangerous condition of CUI with its new line of Heat-Flex CUI-mitigation coatings.

This next generation CUI portfolio is comprised of four products, all of which have passed extensive lab testing, showing good to excellent performance in a variety of tests.

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MIO Helps Address CUI Failure Issues

To better meet the needs of current CUI-mitigation specifications, Sherwin-Williams enhanced three formulations by adding MIO reinforcements. Each coating features a minimum concentration of 25% MIO pigment by weight in the dried coating film, helping to extend the life of the coatings and reduces risk by addressing typical CUI failure mechanisms experienced while in service and during shipping and construction.

MIO-Enhanced Epoxy Novolac Phenolic
For applications requiring high-temperature epoxy novolac phenolic coatings, Sherwin-Williams offers MIO-enhanced Heat-Flex 650. Suitable for CUI temperature ranging from -196°C (321°F) to 205°C (401°F).  With its higher MIO concentration, the coating represents the next generation of the well-known Sherwin-Williams Epo-Phen™ FF CUI-mitigation coating offering higher solids, improved crack and UV erosion resistance.

MIO-Enhanced Alkylated Amide Epoxy
Suitable for CUI temperature ranging from -196°C (321°F) to 205°C (401°F) This coating consistently outperforms comparable alternatives in terms of heat, corrosion, erosion and thermal shock properties. A variety of accelerated testing methods have shown that Heat-Flex 750 outperforms traditional epoxy phenolics and other AAE technologies in a CX environment with no adhesion loss, an excellent rating for rust and blistering, as well as excellent heat and crack resistance at high DFTs, and minimal chalking and DFT erosion.  The products high solids and fast dry times make it ideal to increase productivity. 

MIO-Enhanced Multi-polymeric Matrix Coating
As a two-component version of the company’s original Heat-Flex 1200 coating, Heat-Flex 1200 Plus provides added mechanical resistance and corrosion protection in atmospheric environments. That includes on insulated pipes, valves and process vessels that face very high-temperature service and aggressive cyclic service at high temperatures.

An Ultra High Solids, Solvent-Free CUI Coating Solution

Heat-Flex ACE is a next-generation ultra-high solids advanced novolac epoxy for CUI. Developed with a functional chemical enhancement, surpassing performance capabilities of traditional solvent-based epoxy phenolic and novolac coatings. This advanced CUI epoxy technology is unique and different from other epoxy chemistries, as it gives unrivalled performance and application properties through the robustness of the resin system, rather than through pigmentation. Heat-Flex ACE provides external protection of process pipes, valves, and vessels operating between temperatures from -196°C (-321°F) to 232°C (450°F) and is suitable for use in new construction and maintenance projects of both carbon and stainless-steel substrates in insulated and uninsulated service.

Heat-Flex CUI-Mitigation Coatings Overview

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