In this month’s edition of the Pipeline Technology Podcast sponsored by Pipeline & Gas Journal, Angus Bowie of STATS Group discusses the pipeline challenge limits of leak-tight pipeline isolation.
In this episode, you will learn about how to perform a pipeline isolation, the different types of temporary isolations available, the lessons learned from a major pipeline repair project in extreme conditions, how logistics factors into a pipeline rehabilitation project, the interesting use of 3D animation to support project understanding, and more information.
Show Notes, Links, and Insider Terms
- Angus Bowie is a Regional Director for STATS Group. Connect with Angus on LinkedIn.
- STATS Group (STATSGroup.com) are market leaders in the supply of pressurised pipeline isolation, hot tapping, and plugging services to the global oil, gas, and petrochemical industries.
- Read Angus’ September 2020 article in Pipeline & Gas Journal, “Pipeline Challenges Limits of Leak-Tight Pipeline Isolation Capabilities.”
- Valve Isolation is the use of an isolation valve to effectively isolate between a live plant and the system being maintained.
- Block and Bleed Valves consist of multiple valves used in the system to allow for precise flow regulation when there is low flow in an environment.
- Double Block and Bleed (DBB Valves) consist of two block valves and a bleed valve that operate as one unit to achieve positive isolation in high-pressure or hazardous systems. DBB valves do the work of three separate valves and require less space and have less weight.
- The STATS DNV GL type approved isolation tools provide leak-tight double block and bleed isolation that enables safe and efficient maintenance and repair of onshore, topsides, and subsea pipeline infrastructure.
- Temporary Isolations use plugs to support repairs in a pipeline system.
- Low-pressure isolation or (ambient isolation) is typically used in ambient conditions to isolate the pipeline, restrain hazardous materials in the pipe, and perform repairs.
- High-pressure isolation uses equipment to restrain pressure in the pipeline while the repair is completed.
- Isolation Plugs are mechanical plugs that are placed into one end of the pipeline and pigged to a location to provide a leak-tight isolation.
- Find out more about the Tecno Plug Non-Intrusive Inline Isolation delivered by STATS Group.
- Hot tapping is the process of making a connecting to existing piping without interrupting or emptying a section of pipe. This allows the pipeline system to remain in operation while maintenance is performed.
- Line-stop tools stop the flow in a pressurized pipeline. There are many different types of tools available from vendors.
- Leak-tight-seal isolation is a method for temporary line plugging to support maintenance of live, pressurized pipelines.
- The STATS BISEP provides a fail-safe double block and bleed isolation deployed through a single full bore hot tap intervention, without the need for additional hot tapped bleed or vent ports.
- Read this STATS Group case study, World First: Leak-Tight Double Block and Bleed Isolation on High Pressure CO2 Pipelines.
- The STATS BISEP provides a fail-safe double block and bleed isolation deployed through a single full bore hot tap intervention, without the need for additional hot tapped bleed or vent ports.
- HAZOPs (Hazard and Operability Study) is a systematic review of a complex project or complex operation to identify potential problems and evaluate the risks to people and equipment.
- ALARP (As Low As Reasonably Practicable) is a risk management and safety management term used to quantify the amount of risk that is reasonably involved in a particular project or system.
Full Episode Transcript
Russel Treat: Welcome to the Pipeline Technology Podcast, episode five. On this episode, our guest is Angus Bowie, MENA and APAC Director at STATS Group. We’re going to talk to Angus about his September 2020 Pipeline & Gas Journal article entitled “Pipeline Challenges Limits of Leak-Tight Pipeline Isolation.”
Announcer: The Pipeline Technology Podcast, brought to you by Pipeline & Gas Journal, the decision-making resource for pipeline and midstream professionals. Now your host, Russel Treat.
Russel: Angus, welcome to the Pipeline Technology Podcast.
Angus Bowie: Thank you. Pleasure to be here.
Russel: It’s good to have you. I’m really looking forward to this conversation. Before we get started, could you give us a little bit about yourself and your background?
Angus: Certainly. I’ve been working on pipeline isolation since…Well, I designed my first plug in 1986. I’ve done everything related to this from being offshore, design, projects, everything apart from accounting. I do draw the line somewhere.
Angus: I used to sell computer-aided design systems. I sold a computer-aided design system to the company that isolated pipelines, and then I just programmed CAD for them and then I joined them. I just worked my way up from there. I’m a chartered mechanical engineer based in the U.K., and I’m 59 and getting closer to the end of my career.
Russel: That’s what all good older engineers need to do. They need to pontificate and share their knowledge with the younger generation. Mostly, what we want to try and do is teach them all the things we did wrong so they don’t have to do that. They can make new mistakes.
Angus: Unfortunately, I’ve done a lot of things wrong and had some good experience from the things being more challenging than you would hope. Bringing young engineers up is something that I’m probably most proud of. I brought several engineers to chartership. We do good training programs. I like to think we’ve supplied the industry with a number of good engineers through the last 20, 25 years.
Russel: You’re using the term, Angus, chartership. I’m here in the U.S., and a lot of our listeners are in the U.S. Can you explain what chartership is?
Angus: It’s the same as your professional engineer in the U.S.
Russel: It’s the licensing process for professional engineer?
Angus: It’s professional engineer, yes.
Russel: Yeah, right. Cool. I asked you to come on to talk about pipeline isolation. I have to tell you, Angus, this is a topic that fascinates me, the idea of how you isolate a pipeline, particularly when you’re isolating a pipeline and you’re continuing operations. How does that even work?
Maybe you could talk to us a little bit about just in general what is pipeline isolation and what are the considerations.
Angus: Generally, pipelines are designed like process pipework with valves in the system to allow you to temporarily isolate sections, get in, and do some work.
Within a valve isolation, because valves aren’t always leak-tight, they have a thing called double block and bleed, which is two valves, each holding theoretically leak-tight with a bleed in between them that proves the two valves and allows you to maintain ambient conditions in between the two valves.
The primary one’s holding the pressure, and the secondary one is just stopping the bypass getting to the work site. Where you don’t have the valves or your valves are leaking, you need to use what we’ve described as temporary isolation. There are a number of temporary isolations in the market, and I break them down into two types.
There’s low-pressure or effectively ambient, which are things like gas bags, mechanical plugs, things like that.
Then there’s high-pressure isolation, which allows you to basically hold back pressure in the pipeline while you do the work.
I started off in this industry doing isolation plugs, which are mechanical plugs, which are put into one end of the pipeline and pigged to the location to where they’re hydraulically set. They provide an equivalent isolation to double block and bleed as in two leak-tight seals. The second seal is tested at the full pressure. We vent down the pressure between the seals to ambient, and we test the primary seal.
The other form where you don’t have a pig trap or access to the pipeline is a thing called hot tapping where you put a pressure boundary on the outside of the pipeline with a flange on it, you cut a hole in the side of the pipeline, and you install the tool through the side of the pipeline.
Traditionally, this was done with a line-stop tool, which is a lip seal, which goes in and then you cut another hole for the gas bag, another hole for a vent, and another hole for pressure equalization.
We’ve taken our isolation plug high-integrity standard and put it onto basically a spherical head, which rotates into the pipe and provides the full dual, high-pressure, leak-tight-seal isolation, which gives a much higher level of integrity and safety.
Again, you come back to comparing it to the double block and bleed that you have from the valve isolation, although it’s inequivalent double block and bleed because technically double block and bleed is a valve isolation. I could go on at this for hours.
Russel: [laughs] I’m sure you could. I find this subject fascinating, particularly when you start talking about hot tapping and how that works. For me, it’s very helpful to see pictures of this because it’s hard to visualize this just from conversation.
Said simply, the idea is that pipeline isolation is putting a valve where you don’t have a valve. That’s an oversimplification, but that in effect is what you’re talking about.
Angus: Basically, yes. We’re closing the pipe where there is no closure at the moment to allow you to get in and maintain a section of the pipe without shutting down the whole pipe. We can do this by putting a bypass in so that you can maintain production while you’ve got the isolation in place.
Russel: I asked you to come on to talk about the article that was in the September 2020 Pipeline & Gas Journal that’s titled “Pipeline Challenges Limits of Leak-Tight Pipeline Isolation.” Maybe you could tell us a little bit about what the project was that this article was about.
Angus: It was a very challenging project. We were approached in December 2017 to basically help a client in the Middle East fix a pipe rack that had been damaged. I think it was 37 lines in total that had been damaged that we had to go and look. We had to isolate both ends. Some of them needed to have a bypass. Some of them didn’t.
There was everything here from water, steam, naphtha, hydrocarbons, gas. There was lots of different lines, flare lines. They were all in a high pipe rack which created some challenges of its own. The smallest isolation we actually did was a three-quarter inch. The largest one was 54 inch. They all had to be delivered in five months.
They included steam lines where we had to basically come up with some new solutions for steam. Our seals that we had at that time weren’t good for the temperature, so we had to go and find a new seal material. We needed to adjust the isolation tool design to accommodate the different geometry for the seal material, test it, prove it, and then get it mobilized on the site.
At the same time, we were building all the equipment and delivering the rest of the project on-site. It was a very challenging job to do mostly because of the time. It was very limited time, and we had to do it in this time to get the refinery back up to full production. It was a challenging time.
Russel: Let me run those numbers back again. You said 37 different isolations.
Angus: Different pipelines, yeah.
Russel: Ranging from three-quarter inch up to 54 inches, and broad range of products that are actually in these pipelines. That’s about as complicated as you can make a project like this, and then you add the element of limited time. That pretty much makes this about as complicated as this type of project could get.
Angus: Because we didn’t have time to get all the weld procedures and everything sorted, and they didn’t want to leave any welded fittings on the line, almost all of these jobs were done with a mechanical clamp. We then performed a hot tap, put our BISEP in, our hot-tap isolation in. We then cut the line, put a mechanical connector on, deployed a plug and cut the line.
Then we welded on a flange so that we didn’t have any on-line welding. We had a couple that we did on-line welding in the steam lines. I think everything else was done with mechanical clamps to speed up the process and to avoid any of the pre-qualification of the welding. It also meant that we didn’t leave any fittings on the line, even the steam lines where we used welded fittings, we cut them all out.
We left the line with no additional welded fittings on them other than where we had bypass fittings.
Russel: Fascinating. What did you learn about pipeline isolation in doing a project like this?
Angus: First thing I learned is that working high up on a pipeline with steam lines and boiler feed lines is very hot and very unpleasant. It means what happens is the guys who were working on it — because this was in the Middle East, so we were 52-degree heat in the Middle East, going through the summer — your brain just ceases.
Russel: Just for us Americans, that’d be about 130 degrees.
Angus: Yeah. When I come to measurements in design, I can do imperial and metric, but temperatures I’m metric. There were issues on the pipe racks because guys, they just weren’t thinking straight. We had to be really careful, really procedural, really tidy and everything.
There was a big lesson there. It’s when you’re dealing in really unpleasant conditions, don’t expect people to work to their highest performance. We were 30 meters up on pipe racks. You’re 30 meters up, and then you’ve got 54-inch pipe at the top, then you put a clamp on it, you put a valve on it, and then you put a hot-tap machine.
The guys on the top of the hot-tap machine, it’s quite high up in the air. You have to have a good head for heights to do that. We learned all that. Steam-wise, we learned how to isolate steam. We identified early on that the safest way to isolate steam was to have a high-temperature isolation and then a more standard isolation behind it.
What we did is; the pipe in the racks had expansion loops, which went up, which rose up above the main pipe, which gave us thankfully u-bends, so we would put our very high-temperature seal in the line and cause it to flood.
Once we stopped the flow, we could then come in and put a more standard seal in behind it to ensure that we had a level of safety that we would with traditional tooling while maintaining the full isolation. It worked very well. As soon, as we put the primary isolation in, we closed down, and there was no flow, it worked exactly as it said.
It just condensated, dropped down the temperature. We had to make sure that we had an open vent on the line because if you isolated the mid-section, as you create the condensate, you can draw a vacuum. We made sure that we had nitrogen flowing into the system to make sure that we didn’t create a vacuum while we were doing the system. Lots and lots of lessons learned on how to get that.
We also had some locations in pipe racks where we couldn’t get in vertically above, so we had to come in with a hot tap and the isolation at about 15 degrees to the side of the pipe. This is something we can do with our tooling. The handling of it and rigging of it is really quite a challenging operation.
Russel: I’m sitting here, and I’m just thinking about all of the factors. You mentioned dealing with steam and isolating it. You’ve got an issue with that pipe cooling. As the pipe cools, you’re going to have the dynamics of whatever fluids you’re dealing with changing.
You could have a changing phase. Just the idea of venting that safely or getting that pipe evacuated safely, there can be a lot of complexity in that as well, I would think.
Angus: With pipe particularly, you don’t need to vent it. When it cools, it actually drops the pressure. You don’t need to vent that. You just need to make sure that you don’t generate a vacuum because as it condenses, it condenses actually quite quickly. It goes from 1,000 to 1 is the ratio approximately. It drops down in volume massively.
You just have to make sure that you’re protected against that. This thing we knew before we started. We went through and we designed everything to suit the project. There wasn’t any issues with this on the project. It was just, as I say, once you start doing steam, you realize you’ve got the opposite problems than you have from the hydrocarbons.
With hydrocarbons, the issues are getting the hydrocarbons out of the pipeline, and flushing through, and making sure everything is hydrocarbon-free before you cut the pipeline. Fortunately, with our tooling, the isolation goes in away from the isolated section, so our launcher gives us a bleed port to allow us to put the bleed vent in.
There’s just a lot of it. The water lines we’re venting, when you get even just 16 inches of pipe, if it’s 100 meters long, there’s a lot of water there to come out. You cut a small hole when you open a vent for it to come out, and it just takes a long time. Everything takes longer than you think, is the biggest lesson.
Russel: Having done work, not this kind of work, but having done work in harsh environments, and everybody who does this kind of work, you know going in that everything takes twice as long in the field as it takes in the shop. The other thing you learn is that it takes longer to get started and longer to clean up at the end of the day just because you’ve got to deal with the safety.
Then you add to it extreme heat or other things, height, all that, and now you’ve got to get eight hours work in an eight-hour day, that becomes challenging to say the least.
Angus: You don’t get the eight hours of work in an eight-hour day. You get about 6 hours in a 12-hour day. Best will in the world, we’re on a plant. We need to get the work permits. Then we need to get all the different groups in line. We need to get the guys on site, up the scaffolding.
To get to the site, there was a 20-minute drive to get from the office to get to site. Then it took you another 10 minutes to climb up the scaffolding. You have to have water breaks every 15 minutes when you’re in that heat. It wasn’t that productive.
Getting people into the Middle East has its own challenges. To get visas, we had to get a thing called a mission visa, which is a three-month visa, but it’s a single-entry. The guys who came in, we had to keep in-country for three months because for a job this size, this was twice the size of our previous year’s turnover, this single job.
Plus, we still had other jobs happening. We didn’t stop the rest of our work. We were pulling in from the rest of the world. The guys had to come in, and they had a pretty long stint. A three-month stint is a pretty long stint at it. At the end of the day, it was delivery to client. It was important for the client that we did this to get it together. We were working.
We were contracted to the South Korean contractor who we had some effectively European technical authorities, and then we had our Arab clients at the end of the day. There was a lot of different language, technical discussions, and clarifications going along the way.
Russel: The point I’m trying to make, Angus, for the listeners is that, our listenership is, it’s not exclusively in the U.S., but it’s certainly our core listenership’s in the U.S. The complexity of doing a project here versus doing the complexity of this kind of project, it’s quite different. It’s quite different. You still have all the issues around you got to plan the work.
You got to get your work permits. You got to get out to the site. You still have all those kinds of things. Being able to create a team to do a project of this size, to mobilize that team, deal with all the just people logistics of, that’s a big deal, plus you’ve got all the equipment you’ve got to ship. That’s a big deal.
You’ve got the complexities of the project itself, and then you’re executing the project. I guess you’re probably dealing with at least three different language sets, maybe more to execute the project.
Angus: English was the language of the operations. Everybody spoke English. Because of the many different countries that were there, there probably were half a dozen of languages, so you had to make sure that everybody understood exactly what they did when you mobbed to the scaffolding.
Russel: It takes more time, and it takes an extra level of I would say deliberateness to do that.
Angus: There’s an extra level of management and an extra level of care that needs to be applied to get that done.
Russel: All in the midst of trying to get it done in a hurry.
Angus: All in the midst of trying to get it done in a hurry.
Russel: In a project like this, what’s the things that impact your ability to accomplish it in the time frame? What impacts the speed of execution?
Angus: The domino principle is the first thing. If something goes wrong on one pipeline, when you move to address that, everything else starts to slip back. Make sure that you’ve got resources. Whenever we take on a big project like this now, I have a team of firefighters effectively. It’s not all going to go smoothly on a project of this size that’s rushed so much.
You’re going to get the site, and you’re not going to have a bit of something, you’re going to lose something along the way, or somebody’s going to make a mistake, and we have to go back and do some re-work. The important thing is that you’ve got a spare capacity to address that without disturbing your core delivery team.
What we had if we had one where we had to go and take out an isolation, take out a BISEP, redress it, put it back in, we lost four or five days. That lost that team, these guys were scheduled to go and do another job, it all just kicked back. The other lesson is don’t put all your people on-site.
Because of the shortage of people for visas, we took all the guys from our workshops who had the visas and put them on-site, which means the guys we were bringing into our workshops were the guys from our other divisions. They didn’t know where everything was in the workshop. They weren’t familiar with it. It slowed the progress down.
We didn’t really have any option because you need specific permits to get on-site, so you have to put the guys on-site with the permits. That slowed down the delivery of the next job and the next job.
To give you an indication, when we started this job we got the order at the end of December. By the tail end of January, we were on-site doing the first one of the jobs. We were running all the way through on-site as well as trying to get the supply delivered to site. We were spread quite thin. We ended up putting guys who should have been in the workshop on-site, which meant that the workshop was a little bit inefficient because the guys who came in from the U.K. and from the U.S. didn’t know where everything was in our workshop. They didn’t know where our suppliers were. It just was a little bit less efficient than we would hope.
Russel: I’ve done some international work, and I was always, these large engineering companies that do these turnarounds, and do the construction, and big modification projects and such, it always impressed me that while they’re good engineers, more than being good engineers, they’re really good logisticians.
They really understand what it takes to get the equipment to site, to get the people to site, get the tools to site, to be able to execute the work. They would mobilize us, and they’d have us down on site a day or two before they were ready for us.
They would keep us a day, two, or three after we were done just to be sure they didn’t need us because the cost, not so much the monetary cost, but the project cost of having to re-mobilize was just huge.
Angus: We do that a lot for big shutdowns here, where our guys go on-site. They’re there a week before, a few days before everything’s ready. Everything’s double and triple checked. Everything’s tidied up at the end. We have more equipment than we need on-site so that there’s no hold up to the shutdown. The problem with this one is we had no warning.
We were, from the purchase order, even from the inquiry, moving straight to getting stuff ready to go on-site. We actually started to prepare the stuff even before we got the PO because we couldn’t make it otherwise. We had to start getting stuff ready to go. As soon as guys came in, they went into the workshop for a few days to a week while they got their site pass processed.
Then, they were on-site. We were getting as many people to site as quickly as we could. There’s no point in us putting just anybody on-site. They needed to be fully qualified and experienced people. This is pipeline isolation. This is very, very safety-critical. We had to make sure we had the right people. We brought them in from all over the world, but we had to get them through this process.
It just was tight. Five months was very, very tight for us to do this job. We actually didn’t quite finish it in the five months. We were probably about seven months by the time we finally completed it. They did add in an extra three-quarter-inch and 30-inch steam isolation at the end.
Once we just about finished everything else, they said, “Oh by the way, can you do these, too, because we’ve got these other small problems to be addressed?”
Russel: As long as you’re here.
Angus: Yeah, as long as you’re here. Again, it was one of these things that they weren’t sure that they could actually do them. When they saw us doing the other steam ones, they said here’s something that’s even trickier. To be honest, the three-quarter inch is even more difficult than the 54-inch. It’s a slightly different tooling range to fit things into that.
Russel: That’s right. Super big is hard, and super small is hard. Everything in the middle is more straightforward.
Russel: It’s just the nature of things. Angus, I want to ask a couple of questions just, I’ll frame it a little differently. I’m listening to this, and I’m thinking about what I would take away. I think when you think about isolation and repair that’s really a heavy engineering project. It may be small in scope if you’re only doing a single pipe, but it’s a heavy engineering project.
It really is as complicated as a complete construction project if not more so because I’m dealing with something that’s already in production.
Angus: Many of our projects that we go to, the isolation is actually the most complex part of the whole operation. The cutting out and repairing a bit of pipe is not nearly as challenging as getting the isolation in order to do it, particularly if they want to maintain production while you’re doing the isolation.
Historically, most of our isolations on pipelines and trunk pipelines — that’s where STATS has made its place. We do more in process plants now. It tends to be big projects that we come in and do it in the process plants, big shutdowns.
There is a lot of engineering. We have a lot of design engineers. We have a lot of project engineers. The risk assessments are incredible, the number of risk assessments, HAZOPs, hazards that we go through. You have to make sure that everything is ALARP, which is as low as is reasonably practical for risk, as reasonable practical.
We have to make sure that everybody on-site, not just our guys, but the guys who are doing the scaffolding, the guys are to fix the pipe, the guys are filling the permits and monitoring us, that everybody actually understands what we’re doing, the level of safety we’re getting, and how this is going to operate for the duration. It’s why we have so many animations.
Normally when we go, we’ll sit down with a new team of people where language might be a barrier, and we’ll run an animation of exactly what’s going to happen on-site, showing exactly the level of isolation. When people see us up on the platform cutting a hole in the pipe or cutting a pipe just behind our fitting, they know that we are safe, and they’re not going to get into a panic.
Russel: That’s interesting, the idea of using animation as a way to communicate the project. That’s pretty powerful, particularly in a situation where you’ve got lots of languages involved.
Angus: We employed our first animator back in 1994. That’s how long we’ve been doing animations to explain the jobs we do. In those days, it was fairly complex to get a 3D animation, but we managed it, and we found it was really, really helpful. Everything we do is inside a bit of pipe. By definition, we’re not breaching any boundaries.
You only actually see what we do when you’ve isolated, and you’ve cut the pipe, and you can see in behind it. Animations let us see exactly what’s happening in the pipeline. It’s a very powerful tool to make people happy about how the job’s happening and where they are.
Russel: I would say at least from my standpoint, the first time I saw an animation demonstrating how hot tap works, I’m like oh. It’s just like all these questions I had got answered in a couple of minutes of just watching an animation. It’s really powerful. It’s a really powerful tool.
Angus: It is very, very powerful. We have lots of animations on our website if anybody is interested in basically what we do. They cover all aspects of our tooling and our operations. It’s just so much easier than a conversation or a text. It makes it very clear the level of protection that you’re getting.
Also, when we go and do a risk assessment, we’ll play an animation first so that everybody in the risk assessment team knows exactly what we’re doing and exactly the levels of isolation that have been provided.
Russel: Excellent. What would you want somebody in pipelining to take away about this subject matter? You’re wrapping up our conversation today.
Angus: The most important thing is that pipeline isolation can be achieved in most pipelines. We can leave them in pretty much intact condition when we’re finished. It’s something that should be considered as opposed to shutdowns. Mostly, please take my number, give me a call, send me an email, and we’ll see how we can help you.
Russel: We’ll certainly link all that up on the podcast, Angus.
Angus: Generally we’re very clean, and we will tell you if we can’t do something. Mostly, there’s a few lines that you just can’t get out because of the materials or because of the specific products, which you can’t get elastomers. We also do graphite seals in our isolation. There’s a few things that you can’t isolate. Very, very few. Mostly, they can be addressed with a multi-stage operation.
Russel: Angus, I sure appreciate you coming on to the Pipeline Technology Podcast. I feel like I know a little bit more about isolation than I did when we started.
Angus: Thank you very much for inviting me. I hope I distributed a little bit of knowledge.
Russel: Great. Thanks, Angus.
Angus: Thank you.
Russel: I hope you enjoyed this week’s episode of the Pipeline Technology Podcast and our conversation with Angus Bowie. If you’d like to support the podcast, the best way to do it is to leave us a review on iTunes Apple Podcast, Google Play, Stitcher, or wherever you listen to this podcast. You can find instructions at pipelinerspodcast.com.
If there’s a Pipeline & Gas Journal article that you’d like to hear from the author, please let me know either on the pipelinerspodcast.com website on the Contact Us page, or you could reach out to me directly on LinkedIn. Thanks for listening. I’ll talk to you next week.
Transcription by CastingWords