In this episode of the Pipeliners Podcast, Russel Treat speaks with Alois Multerer of Primus Line about reinforced thermoplastic liner technology and its role in pipeline rehabilitation.

The conversation explores how Kevlar-reinforced composite liners are installed, where trenchless remediation technologies are most effective, and the ongoing industry challenges around inspection, integrity management, and long-term operational confidence in non-metallic pipeline systems.

Using Reinforced Plastic Liner for Pipeline Remediation Show Notes, Links, and Insider Terms

• Primus Line — a provider of flexible trenchless pipeline rehabilitation technology, specializing in safe, reliable, and sustainable pressure pipe solutions for aging infrastructure applications worldwide.
• Trenchless Technology — A category of pipeline installation and rehabilitation methods that minimize excavation and surface disruption.
• Reinforced Thermoplastic Pipe (RTP) — Composite pipe technology that combines thermoplastic materials with reinforcing fibers to provide pressure containment and flexibility.
• Kevlar — An aramid fiber developed by DuPont known for its high tensile strength and commonly used in composite reinforcement applications.
• Sliplining — A trenchless rehabilitation method where a new liner or pipe is pulled through an existing pipeline.
• Composite Technology Development Group (CTDG) — An industry collaboration group focused on advancing composite materials and technologies for pipeline applications.
• PHMSA — The Pipeline and Hazardous Materials Safety Administration, the U.S. federal regulator responsible for pipeline safety oversight.
• API — The American Petroleum Institute, which develops standards and recommended practices for the oil and natural gas industry.
• ASTM International — A standards organization that develops technical standards for materials, products, systems, and services.
• ISO Standards — International standards used across industries to support product quality, consistency, and safety.
• In-Line Inspection (ILI) — Technologies used to inspect pipelines internally using instrumented tools, often referred to as “smart pigs.”
• Composite Liners — Non-metallic liner systems designed to rehabilitate pipelines while resisting corrosion and pressure-related degradation.
• Hoop Strength — The circumferential stress resistance required for pressure containment in pipe systems.
• Field Bends — Pipeline bends formed during installation to accommodate route changes and terrain.
• Offshore Pipelines — Pipelines installed underwater to transport hydrocarbons between offshore facilities and onshore infrastructure.

Using Reinforced Plastic Liner for Pipeline Remediation Full Episode Transcript

Speaker: Welcome to the Pipeliners Podcast, episode 443, sponsored by the American Petroleum Institute. Driving safety, environmental protection, and sustainability across the natural gas and oil industry through world-class standards and safety programs.

Since its formation as a standards-setting organization in 1919, API has developed more than 800 standards to enhance industry operations worldwide. Find out more about API at api.org.

The Pipeliners Podcast, where professionals, bubba geeks, and industry insiders share their knowledge and experience about technology, projects, and pipeline operations. And now your host, Russel Treat.

Russel Treat: Thanks for listening to the Pipeliners Podcast. I appreciate you taking the time, and to show the appreciation, we give away a cool Yeti tumbler to one listener every episode.

This week, our winner is Vash Sant with Trans-Northern Pipelines. Congratulations, Vash. Your Yeti is on its way.

To learn how you can win this signature prize, stick around till the end of the episode.

This week, we speak with Alois Multerer with Primus Line to talk about the use of reinforced plastic liners for pipeline rehabilitation.

Luis, welcome to the Pipeliners Podcast.

Alois Multerer: Thanks, Russel. Thanks for having me, man.

Russel Treat: Well, it’s great to be here. I’m actually in north Houston at the ADV Integrity shop. We just wrapped up the Composite Technology Development Group meeting. Our buddy Chris loves to bring all the best and brightest and get them in a room and have them talk. So that’s what we’ve been doing today.

So if you would, before we dive in, Luis, tell us a little bit about who you are and how you got into trenchless remediation.

Alois Multerer: Yeah. Trenchless remediation about, I want to say about 12, 15 years ago. Started out actually in a completely different field.

Basically, a friend that I had called me and said, “Hey, I have this company,” and it’s a big construction company out of Germany. He asked me to come on board.

I came from another field, and then he pitched it to me and I said, “Why not?” Right?

At that time, he actually allowed me to go in on a global world, more or less. Before that, I was more like punch in, punch out type idea. And now the world opened up in this global world of trenchless pipeline remediation.

Going from the U.S. to Canada to Germany, going from Papua New Guinea to Fiji. So it’s kind of cool. This industry is really cool and it led me to a lot of places in the world. So it’s been awesome.

Russel Treat: So what’s your technical background?

Alois Multerer: My technical background is mostly technical sales. So I got trained from the company for a longer period of time in the engineering study of it.

Russel Treat: Okay.

Alois Multerer: That took about, I would say, almost three years until you’re fully up and running. Now I’m almost 15 years with it.

Russel Treat: Yeah. I think what’s true is a lot of people in our business are engineers, right?

Alois Multerer: Agreed.

Russel Treat: But none of us get out of school knowing what we need to know to do this job.

Alois Multerer: Yeah. They’re not teaching pipelining in university.

Russel Treat: They teach you enough to be able to learn pipelining, but they’re not teaching you pipelining.

And on top of it, if you think about pipelining coming from the pressure side versus the gravity side, and what different types of liners, it’s only like a 30-year-old industry. It’s not that old yet.

Alois Multerer: Right. We put our first liner in in 2002 with Exxon back in the day. Light sweet crude line. We’re 24 years in and still operating.

Russel Treat: I don’t think this idea of internally lining a pipe to rehabilitate it is very well understood or very well known.

Alois Multerer: I 100 percent agree. I think it’s growing, but I think in the industry there’s a lot of skepticism.

Russel Treat: Let’s talk a little bit about what the technology is and how it works.

Alois Multerer: Well, this one is a composite liner, basically an RTP, as they call it. RTP stands for reinforced thermoplastic pipe.

Our reinforcement comes from the Kevlar aspect. Kevlar is an aramid fiber invented by DuPont in 1967. It’s very strong. The tensile strength is like five times stronger than steel, and that makes the hoop strength.

On the inside and the outside there’s a plastic sheet on it, about six millimeters thickness. That then goes inside a hose pipe. So that’s a reinforced thermoplastic pipe as we call it.

Russel Treat: Okay. So what makes that pipe reinforced? What’s the nature of that?

Alois Multerer: It’s the Kevlar part because the strength, the hoop strength, comes from the Kevlar.

Russel Treat: I know nothing about Kevlar as a material. Can you kind of talk to me like I understand plastics and how plastics are moved and formed and all that kind of stuff, but I don’t really understand Kevlar and how that works.

Alois Multerer: Basically, you have to imagine a sock and it’s woven. You have horizontal and vertical strings, and a weaving machine makes those strings into a fabric, kind of like how carbon fiber works.

Russel Treat: Yes, sir. 100 percent.

Alois Multerer: Then it runs from a vertical system, which is about 30 meters tall, on an extrusion process on the inside and outside. That’s where the plastic gets put on.

Russel Treat: So the liner itself, is it like a sandwich layer of plastic and Kevlar?

Alois Multerer: Yeah. Six millimeters thickness. Each thickness has two millimeters.

Russel Treat: That’s really thin.

Alois Multerer: Yes. Chris actually has a sample of mine. I wish I would have brought it in here right now to show you.

Russel Treat: Maybe afterwards we’ll have to go get it and we’ll take a picture and put it up on the website with the show notes.

Alois Multerer: It’s really cool stuff. I just gave a presentation here to the operators. We put two miles, which is 3,200 meters, in a monolithic pipe. The longest pipe in the world into an offshore platform-to-platform application.

There’s a 10-inch carrier pipe in there, and we lined this in one monolithic shot. That’s how long we produced this kind of pipe.

Russel Treat: It’s interesting with this kind of stuff. It’s very hard to visualize how it’s done if you’ve never seen it. Then when you see it, you’re like, “Oh, that makes so much sense.”

It’s kind of like when you do a hot tap. How do you actually pierce and seal up a flowing pipeline? But when somebody sits there and shows you, you go, “Okay, now I understand.”

So how do you actually get this stuff into the pipe?

Alois Multerer: Usually you open the pipe on either the valves on each side. You need a bell hole on each side or somewhere an opening. Usually you either cut it or you go in where the flanges are connected, depending on where the failure is.

Usually the pipe gets prepared. You have to clean it, inspect it, all that kind of good stuff. Then we winch it in. So it’s a sliplining method.

Russel Treat: So you’ve got like a pull line.

Alois Multerer: Correct.

Russel Treat: You run a pull line through and then you use that pull line to pull the liner through.

Alois Multerer: Yeah, correct. It’s winched through.

Russel Treat: That makes sense. So basically you have a winch on one side of the bell hole, and then on the other side is where your liner is. Then you take the winch cable, put it back, take the liner, and slowly put that through all the way to the other side.

Alois Multerer: Exactly. We have winch cables that are two miles long.

Russel Treat: So a couple of questions. You kind of emphasized “slowly.”

Alois Multerer: Yes, because the speed is the pulling force. You have to calculate pulling force because of elongation of the pipe.

You don’t want to just yank on it with 20 tons at 100 meters a second.

Russel Treat: So what you’re saying is we’re not operating a drill bit.

Alois Multerer: Agreed. You just said it. We’re not just trying to pull. It’s more elegant than that.

Russel Treat: If you just take a pull cable that’s two miles long laying on the bottom of a pipe, just pulling that requires quite a bit of force.

Then you’ve got to actually pull the liner. And as you pull the liner through, those calculations change because you have less cable.

Alois Multerer: Exactly. Usually a pulling force calculation is the weight per meter, or here you’d call it feet. Then you multiply that by 0.5 because it’s C-folded and taped.

That’s the beauty of the product. It’s C-folded and taped, so that makes it 0.5 times your length. That spits out a total pulling force weight.

Then when we negotiate bends, and that’s another beauty of this product, I don’t take the field bend out, let’s say a 45 or a 90. I negotiate that bend, and then I have to add weight to the pulling force because through the bend the pulling force increases.

Then I have the winch. Usually small winches start around one and a half tons. They go up to three, five, ten. Offshore, like I just said, we needed a 20-ton range.

Russel Treat: What’s the max distance that you’ve ever run this liner?

Alois Multerer: The max distance without needing a coupling is 2.4 miles. But we had a coupling where we basically put two liners together.

The longest material that we ever produced and installed ourselves is the one I just mentioned that was 2.02 miles.

Russel Treat: That makes a lot of sense for offshore platform-to-platform.

Alois Multerer: Yes sir. Jetty lines, for example.

Russel Treat: I guess the question that comes up for me is the economics. If I had a 10-mile run of straight pipe, then I’d have to access that pipe basically every couple of miles in order to pull this liner all the way through.

Alois Multerer: Correct. From an economic standpoint, you first have to look at where you are on the land.

If you’re out in West Texas, you might just dig it up and replace it with poly pipe. It might just be quicker and easier to plow another one in.

But if you are in constrained areas, like a jetty line, or you have environmental concerns, water crossings, railway crossings, somewhere you can’t really dig, then this technology comes in really handy.

We’re this other arrow in the quiver that says, “Okay, how many technologies do you have? Maybe this one is a good one.”

Russel Treat: That’s actually a really good point. In my experience, and I’m not an integrity guy, I’m more of an operations automation control systems guy, but having done all these podcasts over the years, I’m always fascinated by the number of problems that an integrity engineer has to deal with and the number of tools available in the market to deal with those things.

Alois Multerer: 100 percent. Once I get to the integrity department, I’ve already made it very far within that world because I’ve been through at least two gates before.

Then I come to integrity and it’s like, “Okay, finally I can relax a little bit. I can talk to the engineers that are going to understand what I’m talking about.”

Russel Treat: That’s funny. It’s true though. It takes a while to get to the right people.

There’s the operationally “can we do it,” and there’s all these things that pipeline operators, who are very risk averse, have to think through.

That leads me to another question. Once you have this installed, what does that mean in terms of ongoing inspection and maintenance?

Alois Multerer: This is exactly why we’re here at the right place today, Russel. With Chris Alexander spearheading some of it, the biggest thing I hear out there over 15 years now is, “You have to trust the liner.”

In the pipeline integrity business, you now have all the fancy ILI tools. We used to not have them, now we do. They’ve become standard and we can inspect steel pipe and do a super safe job on it.

Now we put a liner in, regardless of what group of liner it is. The question becomes, “How can I inspect it now?”

Russel Treat: Exactly.

Alois Multerer: We can put a spool piece in and all that kind of stuff, but you can’t really run an ILI tool.

I’ve talked to all the non-metallic groups out there and they’re all saying the same thing. We’re in need of technology that tells the operator something about the liner.

That’s why I came here today, to find out what we need to do now so that 10 years from now that’s a proven technology.

Russel Treat: Because that’s how long it takes to get a proven tech into this industry.

That’s a really fascinating question. I’m making an assumption from my ignorance that you would want to inspect the metal, not the liner.

Alois Multerer: Once the liner is inside, you can’t really inspect the metal anymore because now you took the internal corrosion away.

The liner is self-supportive. That means it carries the pressure itself. On the outside, that corrosion I can’t take off from the inside.

Russel Treat: Is the metal providing any of the strength for containment of the fluid, or is all of that strength coming from the liner?

Alois Multerer: That’s a very good question.

You have two ways of putting a liner inside a pipe. When you have a composite spool of reinforced plastic line pipe, there is either a loose-fit liner with an annular space, which is us, or a tight-fit liner.

The tight-fit aspect puts the plastic right against the wall, and the wall thickness has to be strong enough to absorb that pressure because the pressure is transferred to the host pipe.

In our case, being a loose-fit application, standalone, we take all the pressure. We need the steel pipe as a conduit to hold the ground load so that the liner doesn’t get compressed.

Russel Treat: That is fascinating. That’s a completely different approach than I had in my mind.

It makes sense because you’re building the Kevlar in to provide the hoop strength, and then the metal provides the compressive strength for the ground load.

Alois Multerer: Yes sir.

Russel Treat: In things like underwater applications, where a lot of that ground load is just the head pressure of the water.

Alois Multerer: Correct.

Russel Treat: So that’s why, for example, in this offshore application, the regulator is going to be much happier having a liner and a steel pipe than just having a steel pipe.

Alois Multerer: Exactly. Now you’ve got the carrier pipe, maybe with metal loss, but you’ve also got a liner in there that carries pressure itself.

Even if the host pipe goes, you’ve still got the liner.

Russel Treat: So it’s almost like dual-wall containment.

Alois Multerer: Right.

Russel Treat: That brings up another question. What happens if I lose the compressive containment and the ground falls in?

Alois Multerer: The liner is going to close and you won’t be able to flow under certain circumstances.

If it’s a pressure application and the pipe is always under pressure, nothing happens with our product. If my pipe is always full of fluid and under pressure, if you lose the metal, I still will be around and I’ll still be flowing.

The minute I have slack line or something like that, then I’m going to see it compress. But the moment I put pressure back on, it’s going to open back up again.

Russel Treat: Unless something happens that constrains its ability to open up.

Alois Multerer: Agreed.

Russel Treat: This is blowing my mind a little bit because it’s not like anything I’ve thought about before.

Alois Multerer: We’re used to steel pipe. Then plastic pipe came around. Somebody said, “Can we put a pipe in a pipe?”

Then somebody said, “What about if we had a bend? Can we make something flexible?”

Well, is that really a pipe now? Because a pipe needs to be stiff. Or maybe this is more like a liner.

Russel Treat: Which category does this fit in?

Alois Multerer: That was one of the company’s biggest challenges. Finding standards like ASTM or ISO where the product would actually fit in. That took a long time.

Russel Treat: You mentioned Chris Alexander. I think we ought to give him a shout out.

One of the things that’s really cool about what Chris does is he really understands how to commercialize technology.

Commercializing technology is a lot more than just building something new that solves a problem. It’s answering all these other questions we’re talking about and building the proofs that allow pipeline operators, who are highly risk averse, to make decisions to use the technology.

Alois Multerer: Chris is amazing. He understands what’s going on. He’s bringing people together, so I’m very thankful that I was invited.

Russel Treat: He’s really good at staying connected with the market and knowing what new stuff is going on and who needs help.

Alois Multerer: I think he’s also worried about the next generation.

Russel Treat: Oh yeah, we’re all worried about that.

I have a lot of young people working for me. I’m currently 67.

Alois Multerer: You look young.

Russel Treat: Thank you. I plan to keep working for a long time because I’m having a lot of fun.

The next youngest guy on my team is 55, and the next youngest after that is 35. So I’ve got a very young team.

I hear people talk about millennials and all that stuff. That’s not my experience. These are very motivated, very hardworking, very intelligent people.

But passing along the experience that myself and Scott Williams, our lead developer and primary partner in the business, have built up, that’s a challenge.

Alois Multerer: I see it in my day-to-day business. Programs are written and somebody has to design something based on a program. They just have to check the box without ever really thinking.

They’re being trained differently.

Russel Treat: Somebody graduating university this spring was born around 2005. They’ve never known a time before cell phones or before the internet.

They’ve always been able to get any answer to any question immediately. While that has advantages, it also gets in the way of critical thinking because we had to put it all together from the bits and the bytes.

Alois Multerer: Agreed.

We have our own engineering team, but one thing our company did smartly, and I really have to thank our owners, is they actually have their own school.

Russel Treat: Really?

Alois Multerer: Yeah. It’s partly government-funded, but they train some of their own workers as well.

In Germany, after grade 10, you can go into an apprenticeship program and attend that school.

Russel Treat: There’s kind of an equivalent thing here in the two-year technical universities, especially places like Lamar. They’re tightly affiliated with all the petrochemical facilities along the Gulf Coast.

They train people in the equipment and technologies needed to work in those environments.

Alois Multerer: I’ve been traveling from Corpus Christi all the way around to Mobile, Alabama, talking to operators.

This is the hub.

Russel Treat: Oh yeah. We’re in the hub of the world for this kind of infrastructure.

Alois Multerer: There’s a lot of piping.

Russel Treat: And a lot of old piping. A whole lot of it went in during the 1940s and 1950s.

Alois Multerer: Exactly. So I’m thinking to myself, which pipe can I fix?

Russel Treat: I want to kind of wrap this up.

My first takeaway from this conversation is there’s a whole new technology out there that I had no idea even existed.

I knew about sliplining, but I’d never heard about Kevlar reinforcement where you’re not looking for the metal to carry the pressure load. I’d only thought about it as protecting the inside surface of the pipe from additional corrosion.

So that’s takeaway number one. There’s another tool out there I didn’t even know was a possibility.

The second takeaway is that the need for these technologies and the infrastructure around them to support and maintain them is huge.

Somebody who figures out how to inspect this stuff is going to do well. It’ll be good for them and good for you all.

Alois Multerer: 100 percent agreed. That’s exactly why I came here. How do we inspect these pipes? How do we make the operator feel comfortable enough to sleep at night?

The answer can’t just be, “Trust the liner.”

Russel Treat: “Trust me” is never an answer in our business.

Alois Multerer: Agreed. We can do spool pieces and other things, but it’s not the same as what we can do for steel piping.

Russel Treat: We’re kind of where the industry was in the 1960s with metal pipe.

So here’s my last question. What would you want pipeliners to know? What would you want our audience to hear?

Alois Multerer: What I want them to know is that without pipe, nothing happens in this world.

In our bodies we have veins. Let’s call them pipes. We’ve got to keep them clean. Same thing on our planet. Pipes are everywhere, and they’re the lifeline of this world.

With pipes, we move everything through.

I’m super happy being in pipelining. If there are things going on in the world, recessions or Covid or whatever, this industry is recession-proof in that sense.

If a pipe leaks, you’ve got to do something about it.

Russel Treat: If you’re talking about our modern economy and our modern lifestyle, without pipelines moving energy, we don’t have that lifestyle.

Alois Multerer: One thousand percent agree with you.

I’m thankful that I’ve been making a living in this industry for 15 years. I’ve seen a lot already and I’m super happy.

I’m teaching my son a little bit more and more about it too. It’s a good industry.

Russel Treat: Should we get Benjamin on the podcast here before we break? He’s been sitting over here in the corner being quiet.

What do you think about this whole conversation, Benjamin?

Benjamin: Well, you can’t participate in sales if the one you’re selling the product to doesn’t like you.

Russel Treat: Okay. Words to live by.

That’s awesome. Well, I think we’ll wrap it up right there.

Thanks, Benjamin, and thanks, Luis, for coming on and being a guest.

Alois Multerer: Thank you so much.

Russel Treat: I hope you enjoyed this week’s episode of the Pipeliners Podcast and our conversation with Luis.

Just a reminder before you go, you should register to win our customized Pipeliners Podcast Yeti tumbler. Simply visit PipelinePodcastNetwork.com/win and enter yourself in the drawing.

If you have ideas, questions, or topics you’d be interested in, or if you’d like to be a guest, please let me know on the Contact Us page at PipelinePodcastNetwork.com or reach out to me on LinkedIn.

Thanks for listening. I’ll talk to you next week.