Podcast: Corrosion Under Insulation 86’d by Sherwin-Williams

HeatFlex AEB allows operators to forgo traditional insulation systems and all the associated labor, materials, inspection and maintenance expenses in favor of a spray-applied coating that retains process heat, protects personnel and eliminates corrosion under insulation.

One of our judges noted this technology addresses a significant issue in the chemical industry by eliminating the need for insulation under which corrosion can occur. While painting pipes to prevent corrosion is not novel, this formulation enables the replacement of resource-intensive insulation and improves sustainability. The technology could be used broadly across the chemical industry.

To better understand this award-winning product, I want to welcome Neil Wilds, global product director, Corrosion Under Insulation Testing. Neil is affiliated with the Sherwin-Williams Protective and Marine Products line. Congratulations to you and the entire team at Sherwin-Williams.

Neil: Hi, Traci. It's great to be here. It's fantastic that Sherwin-Williams has actually won yet another award for our CUI elimination-type technology. It will be great to talk to you.

Traci: Absolutely. And we're going to touch base on your award that you won in 2023 a little bit further into this interview. But I want to kick it off with just learning a little bit more about the technology and formulation, and its insulating properties. Can you talk a little bit about that?

Neil: Yeah, no problem at all. The product itself is a waterborne acrylic, which we've formulated with various engineered particles that give you the insulation properties. It can be spray-applied, it can be hand-applied. It can be applied through conventional applications, such as a hopper gun or through dedicated insulate texture spray pumps.

And the really interesting thing about it — what makes it different from everything else that's out there — is the fact that we don't rely upon air mixing during the application process to improve the insulation properties. All of the insulation properties that we have in the formula are actually formulated in there. So what we have in the can is what you get on the steel.

Traci: Now, I mentioned what one of our judges noted while judging the competition: the need for this in the chemical sector. Can we go into that a little bit?

Neil: Yeah. Well, it's not just the chemical sector, but that is a big market for this type of technology. It's actually anywhere where there is traditional-based insulation — so mineral wool, calcium silicate — and when you take into account the insulation system itself, which is made up of the traditional mineral wool, so the mineral-based insulation, and then the jacketing on the outside. And this is where the problem occurs, and this is where the demand is coming from.

Because to install something as complicated as that on valves and complicated pipe structures, you never seem to actually get the thing fully waterproofed. Water gets into the system, and that could be from drift from the plant — so it could be various different chemical species — or it could be just rain or seawater on the coast. And it gets into the insulation, and then that's when the corrosion under insulation starts.

So right from the very beginning, we had market pull from one particular client who was having horrendous CUI problems. And when we actually did voice of the customer, the same was everywhere else. So it was in the chemical sector, in oil and gas — it was everywhere. And basically, they needed to get rid of traditional insulation systems and that jacketing, which is holding the water in. And this is where we actually started the formulation of this type of material to get rid of the jacketing, to get rid of that potential of the water getting to the surface and hence elimination of CUI.

Traci: Now, speaking of the traditional insulation technologies, how does this compare in performance?

Neil: It performs relatively well now. When you talk about thermal insulation coatings in general, we're on to probably the third or fourth generation of insulation technologies. And previous systems — the first generations — were sitting in a thermal conductivity of around about 0.1 ohms per meter Kelvin, which is way away from traditional mineral wool and calcium silicate and stuff like that.

Through iterations, we have a HeatFlex 7000 material, which we're not going to talk about today, but that brought it closer to mineral wool and calcium silicate. But HeatFlex AEB is now really there with the mineral-based insulations. It has a thermal conductivity of 0.043, which is very comparative. But not just that — the good thing about the use of these insulation coatings is that you don't hold moisture in the system, right?

And now with traditional-based mineral wools, once moisture gets into the system, then basically your thermal conductivity drops and your performance drops. So when you compare thermal insulation coatings such as the HeatFlex AEB, which is the latest generation, to a certain extent it outperforms these basic mineral wool and calcium silicate-type insulation.

Traci: And you mentioned the HeatFlex line, which you won the 2023 Vaaler Award for, and AEB has upped the game here. Can we talk a little bit more about the evolution — why you wanted to up the game in this actual category?

Neil: Well, we saw this as an area which the industry needed some innovation, right? The first-generation thermal insulation coatings were good for things like personal protection — so resistance to burns — but they didn't really meet the requirements of what the clients were asking for. The clients wanted to get rid of CUI.

So basically, based upon that, we had to dramatically improve the performance of these types of technologies. So we actually put together a team, a dedicated resource within Sherwin-Williams, both in the labs and obviously myself as the SME, and we actually started on this journey to completely revamp both the mitigation coatings line and the elimination insulation line. And this resulted, as you mentioned before, in the 2023 Vaaler Award. And lately we have won awards for the mitigation side — the priming side — so those hot primers which can be used with traditional insulations.

So the whole project was to try and get away from where we were, where we had huge CUI problems, and we had products which didn't really meet the client's needs, to get to a point where we were meeting everything that the client wants. And in the end, it's the CUI problem which is the issue. If you eliminate the ability of water to get to the steel and you still have the insulation properties equivalent to the mineral wool or the calcium silicate, then you have completely upped the game. We always say we talk about mitigation coatings and elimination of CUI, and that was the whole purpose of this whole project.

Traci: In the submission vying for the Vaaler Awards, you mentioned the energy-saving potential. Can we talk about this with the AEB and traditional insulation? Have you calculated the actual energy-saving potential?

Neil: Yes, we have. There are various things that we've done with regard to this. The typical modeling software that all insulation manufacturers use — both the traditional insulations, and we can use it now with the thermal insulation coatings — has a facility to measure kilograms of CO2 and kilograms of nitrous oxides. So these are figures which are based upon the requirements to heat a tank, right? So if you heat a tank and you're losing that heat because the insulation is not good enough, then it actually calculates how many kilograms of CO2 or kilograms of nitrous oxide you're using in that heating process.

So we can actually do that, and we can model that now. So we can go to a client and say, "This is what you're going to save."

To heat a fire tube within heater treaters in the oil sands, over the winter periods they calculated that they were saving up to 20% on their gas bills. So looking at the modeling, trying to get that right, and then going into the field and actually getting some data, we've actually proven that these types of coatings will work.

Traci: In the beginning, you chatted a little bit about one of your customers. Are there any other customer success stories that you can share with us?

Neil: There are a few that we have at the moment. We tend to use these materials in certain sectors. For example, we can use them for thermal management, and we have various — I can't really name the guys that we've done it with — but we've got various projects which we are monitoring at the moment, be it a storage tank, be it a tank roof, be it a heater treater.

We are actually doing some work now on looking at colder temperatures, so looking at the externals of freezers to try and cut down on the energy that's required to keep those freezers cool. These are big industrial freezers. We also use the AEB in some circumstances when we want to have safe touch as well. It can be used in those areas, and we're constantly looking for different end uses for this.

I mean, one of the things people need to understand is when you're talking about removing — physically removing — traditional insulation and replacing it with a liquid coating, the opportunities are endless. Everywhere where there's a heat issue, there's a solar region heat gain issue, like on tank roofs — all of those areas we could potentially use the AEB. And we are starting to really ramp up on the projects that we actually are supplying to now.

Traci: Let's talk about some of the challenges that you had to address. And you say you're monitoring now, so obviously maybe on the fly you have to address some challenges. But in the formulation, were there things that you had to consider — potential for cracking over time, anything like that?

Neil: Yeah, definitely. It's a really strange thing, because everybody who knows me in the industry knows how I like to break things, right? And the key to that, Traci, is if I know how it breaks, then I know its limitations. So the people in the lab have designed themselves lots of different tests to try and break the coating. And this may be, as you mentioned, cracking — you know, going over film thickness, heating rates going too quick during the actual startup of the project.

But also the other issue that we've had — and, you know, we've spent a lot of time on this — is getting the application right. That's the key. If you get the application right, then you get rid of most of the problems that you've got, right? And this is why with Sherwin-Williams, with the HeatFlex AEB, we adopted this OMA process — this open, mix, apply process — which takes the risk of failure away from the applicator.

If the applicator is using a two-component material, he becomes the formulator, because what they're trying to do is disperse insulating particles on-site. And anybody who knows these types of particles — they're light, they're really light. So any breeze, they just blow in the wind. So yes, we've done all that, and that was a key process that we went through, and it took us maybe 18 months to two years to get that application process correct.

Traci: And I think the simplification and the human factors that come into account really speak to the reason that you won this Vaaler Award — making sure that the industry has the tools they need and they can easily use them. So that's very important.

I want to talk a little bit about — you know, in the chemical industry, we have harsh environments. Let's talk a little bit about how this stands up to that.

Neil: What we do — and it's an interesting question because we get it all the time — is that a lot of the testing that we've done is looking at each individual environment. So we tend to use an international standard rather than a U.S. standard, but because the ISO 12944 standard actually details different environments for different industries. So we know that if we're going into a particular environment like an industrial environment, like a petrochemical environment, we know the testing that has to be done.

And the interesting thing that we've got here with the AEB is that we can use existing systems which have been proven in those environments, and we use the AEB as a functional topcoat, right? So you have the protective coating scheme underneath — be it a zinc-based epoxy-type scheme or zinc phosphate or an epoxy primer — and we actually replaced the polyurethane which would tend to be used with the HeatFlex AEB as a functional topcoat. So we're getting all the corrosion performance, but we're also getting the performance from the AEB itself.

And when it comes to obviously the mitigation primers that we have, we test all those primers for the environments that we're going to see. So for the chemical industry, we've tested the HeatFlex ACE and the 750 in those environments. And again, as I mentioned before, we've tried to break them, and we know they are fit for purpose for those environments.

Traci: Fit for purpose. Exactly. And I kind of wanted to dial back a little bit. We coat what we need to coat, and then we can go back and fix things. So it's a process where you can manually trowel on this compound. Is that true? Is that what I'm understanding?

Neil: Yes. This is one of the great features of the HeatFlex AEB. Because we have all the insulation particles in the actual can itself and it's a one-component material, if we need to do some repairs for some reason — we sometimes get scaffold damage or whatever's going on — you can actually just feather the edges, so cut the material back down to the primer and just trowel one coat. In most cases it will be one coat by trowel.

And because we've got the insulation particles dispersed already and we're not relying on air, the thermal conductivity we have on a hand repair is exactly the same as we do on a spray application. So we're not losing any performance. So it becomes really, really useful. And the fact that it's a one-component material makes a massive difference. They can actually just mix a pail up, tip some out, seal the pail back up, and they're away doing the repairs. And then they can go back to the pail again. Can't do that with two-component materials.

Traci: Let's talk a little bit about the markets and the availability of it.

Neil: The markets, as I mentioned earlier on, could be anywhere. I mean, I've seen CUI in hospitals, power plants. We have some queries in South Africa for boilers in houses — so water boilers in houses. But generally speaking, we're concentrating on the chemical industry and the oil and gas industry. They're the big ones that we see as important to us and important to the client to try and improve.

I mean, we've all seen the issues on TV and on the internet about, you know, what happens when CUI goes badly wrong. It can be loss of life as well as loss to the environment. So it's extremely important. So we're targeting the chemical industries and the oil and gas industries. It could be anything — could be valves, pipes, tanks, vessels, anything which actually is an engineering nightmare to insulate with traditional materials. This is where the HeatFlex AEB will be a great asset.

Traci: Well, CUI is certainly the unseen danger lurking, so definitely needed. What happens from here? Where do we go from here? How do you up the game from this point?

Neil: Well, we're doing stuff at the moment. As I mentioned, Sherwin-Williams has dedicated a team of chemists and scientists to actually try and go further. We are really in this game to advance the industry when it comes to insulation.

So if you take the AEB as it stands at the moment — it's a one-component, it's a waterborne material — one of the key things that we want to try and get away from is the need for releasing water from the system, because that's what slows down the system: the release of water. So we're looking at potentially going down what we call a fast-reaction route. So basically looking at various technologies which we could replace the HeatFlex AEB with but have something which is much tougher.

We could insulate on the shelf. So basically, instead of doing lots of projects in the field from an OpEx point of view, we're looking at basically, can we coat vast lengths of pipes and valves and have them on the shelf pre-insulated? That would be the game-changing way forward for liquid insulation.

Traci: Well, Neil, I want to thank you for dedicating your life to breaking things and figuring out how to best fix them. And I appreciate your insight on your award-winning innovation here.