Sherwin-Williams has launched Heat-Flex AEB (Advanced Energy Barrier), a single-component thermal insulative coating designed to replace conventional mineral-based insulation on storage tanks, process vessels, and piping. The premise is straightforward: corrosion under insulation requires insulation to exist—so removing it eliminates the failure mode entirely.
The new coating can retain operating temperatures up to 350°F (177°C), with excursions to 400°F (204°C), positioning it as a functional substitute for the mineral wool, cladding, and hardware that make up traditional insulation systems across industrial facilities.
Sherwin-Williams announces Heat-Flex AEB
Sherwin-Williams introduced Heat-Flex AEB as a direct replacement for conventional mineral-based insulation systems. It targets storage tanks, process vessels, and piping — the asset types where CUI has historically driven the most damage and the steepest maintenance costs.
It’s a 1K (single-component) product, meaning no mixing before application. Workers open the container, mix, and spray it over a corrosion-protective primer applied directly to prepared steel. Sherwin-Williams recommends Heat-Flex 750 or Heat-Flex ACE as compatible primers. With a maximum sustained operating temperature of 350°F (177°C) and short-term excursion capability to 400°F (204°C), it covers a wide range of industrial process conditions—without the bulk of traditional insulation assemblies required.
Why CUI Is a persistent problem in industry
Corrosion under insulation is exactly what it sounds like: metal corroding beneath insulation where nobody can easily see it. The mechanism is simple but hard to stop. Water penetrates conventional insulation systems — mineral wool, metal cladding, and all the hardware holding it together — and gets trapped against the steel underneath.
Once moisture is stuck there, it creates a corrosive environment that builds slowly and invisibly. By the time CUI is detected, significant structural damage may already be done. Inspection is expensive and disruptive, often requiring partial or full removal of the cladding.
Moisture accumulation inside traditional insulation also causes thermal efficiency to drop. Facilities compensate by increasing process heat, which pushes energy consumption up. The insulation that was supposed to save energy ends up costing more of it over time. Conventional mineral-wool systems are inherently vulnerable to this cycle — the combination of insulation material, metal cladding, wiring, pins, and banding creates multiple entry points for water and few reliable ways out.
How Heat-Flex AEB eliminates CUI by design
The logic behind Heat-Flex AEB is blunt: CUI requires insulation to exist. Remove the insulation, and you remove the failure mode.
Neil Wilds, Global Product Director for CUI at Sherwin-Williams Protective & Marine, put it directly: “By removing this from an asset and applying the thermal insulative coating in its place, there is no longer any physical system under which corrosion under insulation could occur. Therefore, the corrosion under insulation is eliminated by default.”
Replace the physical insulation assembly with a thick-film coating, and there’s simply no layer beneath which water can get trapped. Getting there required careful engineering at the molecular level. Wilds noted that the development team had to manipulate the coating’s molecular structure and formulation to ensure it could retain process heat at temperatures high enough to genuinely substitute for traditional insulation—without affecting material flow inside the assets.
Unlike mineral wool, which loses thermal efficiency as moisture accumulates, Heat-Flex AEB maintains consistent thermal performance regardless of environmental moisture. That consistency is a real functional advantage.
Operational and safety advantages during application
Installing traditional insulation is physically demanding and hazardous. Workers wrap, band, and clad insulation in close proximity to hot equipment. Heat-Flex AEB changes that dynamic significantly.
Spray application keeps personnel at a safer distance from hot surfaces during installation. Assets can stay operational at up to 148°C (300°F) while the coating goes on, which minimizes process disruption and removes the need to shut equipment down for insulation work. There’s also an immediate safety benefit once the first coat is applied—a single coat instantaneously reduces surface temperature, eliminating burn risk for anyone who needs to approach the asset afterward.
New assets benefit from a more efficient installation workflow as well. Instead of wrapping and cladding equipment on-site — often in constrained or elevated spaces — new assets can be coated in pre-assembly yards before they ever reach their final location. That’s a meaningful efficiency gain on large-scale industrial projects.
Sustainability and cost implications
The sustainability case for Heat-Flex AEB works on several levels. The most direct benefit is asset longevity: eliminating CUI extends the service life of steel infrastructure, cutting the environmental and financial cost of replacement and unplanned maintenance.
The coating also removes an entire supply chain from the equation. Manufacturing, shipping, and storing mineral wool, metal cladding, wiring, pins, and banding hardware all carry environmental costs—Heat-Flex AEB replaces that whole material assembly with a single product. Consistent thermal efficiency means facilities don’t need to compensate for insulation degradation by running more process heat, which directly reduces energy consumption over the asset’s life.
Sherwin-Williams positions the product as contributing to lower carbon footprints across industrial operations — a claim grounded in the combined effect of longer asset life, reduced material production, and stable energy usage over time.
Stable energy consumption is supported
Heat-Flex AEB is a spray-applied, single-component thermal insulative coating designed to replace mineral-based insulation on industrial steel assets. It retains operating temperatures up to 350°F (177°C), handles excursions to 400°F (204°C), and is applied over a corrosion-protective primer directly to prepared steel.
Its core proposition is structural: eliminating the insulation layer removes the physical conditions required for CUI to develop. Thermal performance stays consistent regardless of moisture exposure, unlike conventional systems that degrade over time. Application is safer than traditional insulation installation—assets stay online during coating, spray application keeps workers away from hot surfaces, and new assets can be coated off-site in pre-assembly yards. On the sustainability side, the product reduces material waste, extends asset life, and supports stable energy consumption across facility operations.
Kelly is an experienced writer with 15 years of experience exploring the big stories that shape our world, from tech breakthroughs and space exploration to climate, energy, and the fascinating quirks of science. She has a talent for turning complex ideas into sharp, memorable insights that stay with readers long after they’ve finished reading.
