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Episode 14: Cooler - A breath of fresh air for the KTR | KTR Systems


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Julia Ures: Good to have you with us. Welcome here to "In Sight KTR" with a new episode, which today has the motto: "Fresh wind for KTR". That's because today we're talking about the coolers. And you already know that, I usually either have guests joining us online or guests here live in the studio. And so the latter is the case today. Two guests who have accepted the invitation today, who once again don't know what questions to expect today. And I would like to introduce them to you briefly. We have Joachim Grunwald here in the middle, Product Manager Cooling Systems at KTR Group worldwide. He has been with the company for 14 years. Welcome, glad that you are here!


Joachim Grunwald: Thank you!


Julia Ures: And Franz-Josef Hoffmann is also today's guest at "In Sight KTR", project engineer at KTR Systems, with the company for four years. And also to you, glad to have you here.


Franz-Josef Hoffmann: Thank you for the invitation!


Julia Ures: I have already spoken to some of your colleagues here over the course of time, almost all of them from the field of drive technology. So that was the main topic earlier. Today we're going to talk about coolers. How do coolers actually fit, Mr. Grunwald, into KTR's portfolio?


Joachim Grunwald: Yes, well, the start for us was, as already mentioned, 14 years ago. In addition to drive technology in the field of couplings and the like, KTR also produces hydraulic components. And the idea at that time was that cooling should be added to the hydraulic components. Accordingly, for aggregates and the like, the so-called hydraulic cooling. And that's where we started back then, building up a program. That is today in the area of OAC, so in the responsibility of Mr. Bettmer. And then later on we simply started to supply many couplings for combustion engines and the like, we wanted to expand. And so we actually came or started out of the market where I was before. I was previously with an American company, a large corporation, which is in the field of cooling also automotive and the like. And we then really started to sell and develop cooling systems to these customers as well.


Julia Ures: Mr. Hoffmann, if you take a look around the website, you'll find lots of letters and abbreviations when it comes to coolers, OAC, MMC, for example. And the viewers of "In Sight KTR" ask what the difference is? Can you perhaps briefly explain the different cooling systems? How do they differ and what are the areas of application for them?


Franz-Josef Hoffmann: Basically, you can say that we have two areas, one is OAC and what the abbreviation means is Oil Air Cooler. This is the area of standard products that are mainly used in the hydraulics sector. These are classic catalogue products. I select according to performance how I need this oil cooler in my application, i.e., normal cooling, heat exchange, and heat dissipation. Then there's a second area, and that's where we're here today to answer questions, I hope, in the area of engineering. This means that the coolers that we define are predominantly used in the Mobile Machinery Cooler, or MMC. So this area is relevant for mobile drive technology. The predominant part is the engine cooling, that is, the complete cooling, cooling systems including hydraulics. And there, of course, tailor-made systems are required. For small series, because off-the-shelf or laboratory conditions that you have in standard products, don't apply here. That means we produce, we develop complete cooling systems from scratch, from the lamella to the finished system. And that is our field. And the field of application is diverse, from the normal wheel loader to a road paver machine, also in agriculture. The machines are so diverse and that's why it's so exciting to get to know new inquiries, new projects, new machines every day.


Julia Ures: There was a question whether the coolers are also used in the refrigerator?


Franz-Josef Hoffmann: Not so much there. There are a lot of different technologies in coolers. Be it tray coolers, be it (unv. #00:04:12.9#)coolers and all these other things. We have a special technology, plate and bar, that's what it's called in the industry, which is made for the heavy-duty area. That is, heavy systems that can also withstand vibrations, dirt, shocks, pressures. In the cooling sector, there are others, heat exchangers, which represent other technologies, and thus our systems are not used there.


Julia Ures: Mr. Grunwald, can you also, let's say, open up new markets, new customer groups with the cooler product line?


Joachim Grunwald: We are relatively familiar with the markets where we are nowadays, where we are active. Traditionally, we build coolers for combustion engines, we build coolers for hydraulic units and the like. But of course also special applications for various markets, electronics cooling and the like. And new markets, yes, somehow obviously, we have the turning point somehow, that we are now at some point thinking more and more about, automotive suggests that we have to go into the area of electronics cooling. And that will certainly be another challenge for us. But now traditionally, the markets are known, we are also aware of the different products, Mr. Hoffmann has just said it so beautifully, a refrigerator has a different cooler than a construction machine. And that is why we are actually, our markets are known to us and in these we work and move.


Julia Ures: Let's dive a little deeper here, Mr. Hoffmann. The coolers you build are intended for complex applications. And the process of how the customer gets the cooler that suits his needs will probably not be standard either. Can you take us through this process a bit? What has to happen for a cooler to actually be produced?


Franz-Josef Hoffmann: That's quite an exciting story. Standard doesn't exist at all for us. The standard refers to an aluminum plate or an embossed slat. And that's where the standard ends. We then combine these into a system. It's important to understand and talk to the customer about what the application looks like and what the customer's requirements are. And not just to look at the machine, say I need 100 kW of heat output and I have this and this volume flow, and define a cooler. That would be much too short. Here, it's also a question of entering into a dialogue with the customer to understand his machine. In other words, to understand the applications, the requirements. Only from this does an overall system emerge. In principle, you have to internalize all the framework conditions, whether they be standards, other legislative requirements or constantly changing operating conditions, so that you can then generate the right system. It sounds very complex, and it is, but it's fun.


Julia Ures: When we talk about this complex product development process, Mr. Grunwald, I can imagine that there have been some very special projects and very special coolers that you have built. What was perhaps the biggest?


Joachim Grunwald: The largest we have built so far is about 2.20 meters in height, I would say, and about 2.50, 2.60 in width. The approximate weight of this part is 700 kilos.


Julia Ures: Where is this used?


Joachim Grunwald: That was installed on a road milling machine. So we've built several in that range. So that's, the engine range is about 800 kilowatts of power in that range. And the fan that was installed there had a power consumption of 69 kW alone. So those are already very large. And 800 kW is of course the limit for us, in this area we work or up to this area we work and below that..


Julia Ures: What makes a project special for you? Is it the size or maybe something completely different?


Joachim Grunwald: Nah, the challenge. The size doesn't matter. So you can really also sometimes work on small projects somewhere, I've made a few such boxes where electronics have been cooled inside, where really closed boxes, where work has been done with circulating air and the like, where simply really the technology was so complex that one simply said, that's fun, the challenge. Or really, we also deliver to various engine manufacturers and the like, to really get so deep into the substance of the engine. How does the system work? So with the an engine manufacturer or any construction machine or agricultural machine manufacturer, you really get a deep impression of how the machine works. You see the hydraulics, you just actually get the complete know-how revealed by the customers. And that's fun. So when the project is finished afterwards and you see the success, that makes the whole experience worthwhile.


Julia Ures: Mr. Hoffmann, I've heard you're currently building a test bench for coolers, something like a wind tunnel. Can you tell us a bit more about that, please?


Franz-Josef Hoffmann: Data validation is, of course, an important topic for the future as well, in order to address new customer groups, to serve the customers, and to answer their questions. In addition, it is also about data, we simulate the coolers, we calculate the coolers, everything nicely in the new digital world. We use all the little helpers that we have. But the reality is different. As I said earlier, laboratory conditions do not prevail on site. In order to demonstrate this and work out the finer details of a cooler, you naturally need a test bench. It was a very good decision to set up a test stand here at the site. There, we can also test complete cooling systems, be it water coolers, air coolers, oil coolers and so on. We can run through them accordingly. Here we can also show the real conditions, as far as it is possible and as far as it is known by the customer, what this looks like. And thus we become safer, the products become even more serviceable. And I don't think anyone in the field wants to experience a failure of a cooling system when a road paver breaks down somewhere because of a hot engine and there are 20 trucks with hot tar behind it. Then you can imagine that there will be a number of phone calls.


Julia Ures: And that is associated with high costs in the consequences.


Franz-Josef Hoffmann: Yes, of course.


Julia Ures: You always send us questions here for the "In Sight KTR" format to And the next question is also one of those. And I would like to encourage you to continue to send us your questions to the mentioned e-mail address about the topics or about everything around the company KTR that interests you. We have a wide range of topics in preparation for the next episodes. And for today's episode on the subject of coolers, Mr. Grunwald, a question has come up which takes a look into the future. How do you think the cooler business will develop in the next few years? And are there any trends that are emerging and that you take into account in your work?


Joachim Grunwald: That is quite a difficult question now. I think we're all asking ourselves that question at the moment. I have heard from various friends and the like, where we sometimes talk together, for us, as I have just said, the classic issue at the moment is the cooler for the internal combustion engine. We have the turnaround in passenger cars, it has to be said quite honestly. This was initiated a few years ago and is now being implemented in a really focused manner throughout the entire sector. Various manufacturers of construction and agricultural machinery have already announced that they will of course follow suit. We are always a bit behind the automotive sector, they are running ahead of us by a few years. We will deal with this topic. We are also fortunate, of course, that if you open up any passenger car or vehicle today and look at the electric drive, you naturally have a lot of cooling in there. So of course we will, also these cooling systems also fit to us that are used there. Thus, of course, we will have to develop further and become active in this area at some point. At the moment it's just that, what you see of the off-road machines, that most are still a bit wait-and-see. Because, of course, the development is also associated with considerable costs. And that's our challenge for the next few years, that at some point we will also serve these markets more and more when our customers are ready. But I also believe that other technologies will have to be developed first to make this possible. We currently have the problem that if you take an electric drive and have a machine on a construction site, it's not easy to charge it afterwards and also to draw on this power. Many things will have to be developed for the whole thing so that we can really use it. And that's what we'll do. That's why I'm actually quite confident that it will perhaps change a bit for us, that the market will change a bit, that it will change a bit in terms of drive technology, but that we will continue to serve these markets.


Julia Ures: The slogan of "In Sight KTR" is: Quick questions, concrete answers. One quick question to finish. Perhaps, Mr. Hoffmann, you could start. I would like to ask you both, if we were to draw up a wish list or if the wish fairy were to come, if you were allowed to choose where one of your coolers would be used, what would be an area of application that corresponds to your wishes?

Franz-Josef Hoffmann: I think that would be aeronautical engineering. Because it's a very exciting topic in aeronautical engineering. Here you have to say that coolers are basically a forced product where I need to dissipate heat. And especially in electronics, as Mr. Grunwald has just said, electrical cooling, which we are already doing today with suitably dimensioned coolers, we also cool the engine compartment. That has to be said. But electronics cooling is a huge challenge, both for cars, but the energy density of construction machinery, of large machines, is becoming much more interesting. And aeronautical engineering, that would be an area that would be highly exciting. That's where I come from, I wrote my diploma thesis there, so I have a network there.


Julia Ures: Then this is relatively obvious.


Franz-Josef Hoffmann: And that's why maybe going back to the roots, that would be exciting.


Julia Ures: Mr. Grundwald, what is it like for you, where would you like to see one of your coolers put to use?


Joachim Grunwald: Mr. Hoffmann has obviously already taken the best area away from me.


Julia Ures: You are welcome to join.


Joachim Grunwald: I would join, of course. So I also think aviation is certainly something where you really, what I imagine is very complex. I don't know the cooling system of a Boeing or something like that or an Airbus machine. But that would certainly be a topic where I would say, that would be a project, as you said so well, for which we could create something someday. And otherwise, I have to say that every project has a certain appeal when you get deeper into it. So that's why I can't necessarily say that I only have to do this one or want to do that one or something. The next person would probably say they want to make one for a sports car or something. For the cooler manufacturer, that's boring, because that's a relatively simple cooler. Whereas that or a military machine, a special one somehow, where there's a lot of electronics involved or something, those are interesting projects.


Julia Ures: Then I'll keep my fingers crossed that one day perhaps one of your coolers will also be used in aviation. I would like to thank you very, very much for being my guests here in the studio today. Mr. Hoffmann and Mr. Grunwald, thank you very much! And, of course, many thanks to you for watching and listening. And with this we say goodbye under the motto "Fresh wind for KTR" with everything around the coolers until the next time, to the next episode of "In Sight KTR". Take care!


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