Show notes
Brett Tollgaard from Sunrez discusses their new leading edge protection solution, created using a durable UV-cure resin system. Using this solution reduces downtime due to quick cure times and strengthens leading edges for years to come.
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Bret Tollgaard: Bret, welcome back to the program. Thanks for having me. Appreciate it.
Allen Hall: A lot has happened at Sunrez and you guys are the magic UV cure resin systems that everybody is using at the moment, but there's a bunch of new products that are coming out that I think a lot of operators and ISPs need to be aware of.
One of 'em. Is a fill of material that looks great when you're trying to fix the leading edges, which are just mangled from all the dirt and debris and rain. It's not something you can just kind of smooth over very easily. And a lot of times operators spend a bunch of times sanding, grinding, trying to get it where they can apply some sort of liquidy coating to it, and it never really looks great and it's not really smooth.
Bret Tollgaard: Sunrez has fixed that. We sure have. We've got a lot of customer feedback about some of the things that they'd like us to expand our UV cure portfolio on, and one of the big ones was leading edge protection. There's been a ton of different solutions and stuff used over the years. Some with success, some.
Slightly less mild [00:01:00] success. Uh, and so we thought it was an opportunity kind of right for the picking. And so, uh, the chemist spent a reasonable amount of time trying to develop a highly filled, uh, UV curable resin system that will live up to all the abrasion, whether it's rain, uh, you know, particulates in the air, et cetera.
And so we've undergone some really reasonable rain erosion testing thus far, and it's shown to be a pretty good result. And so it's been a slightly soft rollout as we really kind of finalize the formula in the system. But we really do think it's a product that the, uh, customers are gonna love, whether it's a pre impregnated, uh, fiberglass version, or potentially a, a putty version as well.
Joel Saxum: I mean, the LEP market is, you're always hearing about new LEP, right? There's this LEP test, there's a whole conference devoted to leading edge erosion that. The DTU puts on, but it's because it's such a prevalent issue, right? Like. Alan and I in the field looking at reviewing blade damages for lightning and things.
But we see all, all kinds of leading edge erosion. That is, it's crazy how annuity these turbines, some of these turbines are a [00:02:00] year, two, three years old, they're still in warranty and the leading edges look like they've been hit with a sandblaster. It's crazy. So the fact that you guys are working on something and what we really like, of course, about the UV cured products is that you get up there, you put it on, boom, you hit it with the uv.
You come off the tower, you turn it back on. 'cause a lot of operators, and this is, this is where sun really shines. A lot of operators are always talking about downtime. Downtime. When we talk about installing strike tape, how long do I need to leave the turbine off before? Well, we've working on some solutions.
We don't have to, uh, but. It's a, it's a very common thing and I really, what I really enjoy about what you said was customer feedback. So that means that you guys are in the market, you're trusted in the market, and people feel, feel good enough to come back to you and say, Hey, what about this? What about this?
What about that?
Bret Tollgaard: Yeah. It's kind of similar to our pre pprs. We originally offered those in 300 millimeter by 750 liter flat sheets. Uh, millimeter, excuse me. It got [00:03:00] everyone kind of on the game experiencing some of it. And then with some more customer feedback, we said, Hey, how can we improve the product, the packaging, et cetera.
And they said, 10 meter long rolls of this exact same product would be fantastic. We have less overlaps. We can cut to size, get to shape a little easier, uh, and so we're always constantly trying to get more customer feedback so we can adapt and tailor our products to the markets that we're in. And with that LEP is just a tremendous opportunity to really.
Try to, uh, fast track some of the opportunities to get blades back, uh, spinning quicker
Allen Hall: because there's really two ways of attacking the leading edge erosion problem. And I think United States is a little bit different than what would happen typically in Europe, uh, especially up north where it's mostly rain impact.
What happens in onshore for the United States is I think a lot of dirt impact dust. Mm-hmm. Dust, dust, dirt, right. Bugs
Joel Saxum: till tillable soil. Whenever we see turbines near or downwind of tillable soil, the leading edge erosion always seems to be bad.
Allen Hall: So you're kind of getting hit with a [00:04:00] sandblaster. Yeah.
Yeah. And that's what it's like. Tip speeds are 200 miles an hour, 90 meters a second. You're hitting all this debris in the air and it just beats the heck out of these blades. That's why the OEMs are having problems in those areas. Kansas, Iowa, all those areas are a problem. So the soft materials aren't necessarily the best for that environment.
Mm-hmm. Great For offshore. A lot of places
Joel Saxum: Absorbing rain. Droplets
Allen Hall: rain, yes. And the testing shows that, but in the Midwest, in the United States and some of the areas, India, another place really harsh, where soft is probably the not the right solution. Something a little more durable, harder wear resistant.
Is the right solution and that's what Sunwest
Bret Tollgaard: has developed, correct? Yeah. At the end of the day, everybody wants a rubber rock. Something that can take and withstand, maybe deflect some of the energy coming at it at the same time too. Being sturdy and strong enough. Uh, to have all the wear and abrasion resistance.
And so once again, we've been formulating UV cure resins for [00:05:00] decades. Yeah. And so we've had filled products, unfilled products, et cetera, and you manipulate some of the different concentrations of different additives in there and you can really kind of tailor and tweak the performance. And so. Uh, with that we have the ability to, once again, kind of pre impregnate some fiber in case people want to just wrap and do something kind of similar to the other film type applications.
Uh, but then once again, we also are able to provide that in a putty form and so we can change and adapt the viscosity to meet a certain customer's needs. And really kind of then based on more potential OEM and ISP feedback. As to the processes that they'd both, uh, like us to explore the most, we can certainly go down that path, uh, a little quicker
Joel Saxum: with a putty.
So I'm thinking, in my mind, I'm picturing a really nasty leading edge ocean problem on a blade. Is there a thickness limit to a UV cured product?
Bret Tollgaard: There is. And the more filler you add, the more difficult it is to penetrate through all of that. Yeah. And the, the pre impregnated repair patches, we, uh, have right now, the 73 55 resin formula, we can truly do an inch or a half inch thick, excuse me, of prereq.
[00:06:00] So fiberglass and resin, right? Um, so 12 millimeters in under 10 minutes. So a
Joel Saxum: pretty, there's nothing that you're gonna run into that's gonna be worse than that. Oh, and, and that's
Bret Tollgaard: just it. So the more fillers you add, it can change the color, it can change the wavelengths, uh, that actually penetrate through that, uh, resin.
So we do a lot of testing, um, to really dial in a photo initiated package to maximize that with the, uh, materials that we have inside the resin. And so this new, uh, system that we're working on is our 73 0 3 resin formula. Uh, and it's proving to be a pretty resilient system. Uh, we've done quarter inch thick trials thus far.
As we thought that would kind of gonna be the maximum that people were gonna be looking at. But we do have the capacity to do more if required
Allen Hall: because the, the magic, and this is hard for engineers to think about when you want something that's really stable on the leading edge of a blade, what you're trying to avoid is a sort of a layering system.
If you look at a lot of [00:07:00] epoxies that are apply that are. Structural epoxies, what they are is sort of a cross-linking process, and that cross-linking process also makes it sort of breakable. Mm-hmm. So if you hit it just right, it wants to fracture like a glass almost. It's not that way, but it's similar, right?
So the magic that sun rests has done is said, okay. I'm gonna take a system that's cross-linked together, but also a little amorphous to take those impacts without fracturing and wearing away, because it's the chipping and that's what you see on leading edges for a lot of the epoxy. Yeah. It doesn't look like it's a, doesn't look like it's been a braided.
Yeah, it is, but it's fracturing. So you're getting these like mini explosions that are happening in a sense, and it just wears away. And then you're exposing fiber. And fiber doesn't like that. Mm-hmm. And then it just starts to wear burl into where Joel's pointed out, you can put your fist in some of these blades.
Yeah. That are only a year or two old is crazy. Yeah. And I [00:08:00] think that's where the industry sort of missed one of those areas. You could design a material.