Örjan Andrén has worked at Projekthydraulik since 1988 and has followed the development of both the industry and the company ever since.
– I started right after completing a hydraulics programme at Dalarna University in Borlänge, where Projekthydraulik had been brought in to teach the hydraulics part of the programme. That programme was somewhat unique because it already combined hydraulics with control engineering. Many of those who work successfully in the hydraulics industry today completed that programme. Unfortunately, it was discontinued after only 10 years, he says.
Courses in many areas
Projekthydraulik Haglind & Jansson AB was founded in 1977 in Borlänge by Olle Jansson and Ove Haglind. The two had previously worked in the hydraulics industry for many years and, in their earlier roles, had seen the need for training and consulting within industry companies and manufacturing.
– The company grew and by 1998 had six consultants and trainers. At that point, the company was sold to the Institute of Applied Hydraulics (ITH), which remained the owner until 2002. Then those of us who worked here decided to buy the company back together. The training concept is based on a number of shorter courses, lasting between 2 and 5 days, which can be combined into specializations in different areas such as system design, maintenance and applied hydraulics. They also create specially adapted courses, primarily for industry. These can be focused on a specific type of machine, such as presses.
– Different combinations of courses can also lead to certification in areas such as proportional technology, assembly technology and basic system design. As a training company, we are also certified at the highest level by CETOP, the European Committee for Fluid Power. Being one of CETOP’s approved training centers means that they meet the requirements in CETOP’s guidelines for approved centers and the processes associated with quality assurance and quality control of competence-based qualifications.
More short-term economics
Although Örjan Andrén has been involved for a long time, he does not believe that the basic design of an industrial hydraulic system has changed very much since he started.
– What has changed is that more electronics and control technology are used today, and there is also a greater focus on energy efficiency now than before. When I started, the most important thing was to build a system that was reliable over a long period and easy to maintain. Today, there is not the same focus on durable systems. In his view, it is the economic conditions that have changed; they have become more short-term.
– In times of quarterly economics, you must be able to show that an investment will pay for itself within a couple of years. One example I experienced was when a large industrial company some years ago began a collaboration with a hydraulics network in the region. The purpose was to test whether it was possible to improve the energy efficiency of an existing hydraulic system. The changes we implemented then reduced energy consumption by 58 percent while operations functioned just as well or better. However, the company decided not to proceed and make the same energy-saving changes on the other production lines, more than 10 of them, which were identical. The reason was that the measure only saved SEK 200,000 in one year and the investment was around SEK 500,000, so because it did not pay for itself within two years it was considered too expensive. He notes that one dilemma remains that engineers and economists do not speak the same language.
– As I see it, that contributes to delayed innovation in hydraulic design and means that we do not develop more efficient and sustainable systems as quickly as we could.
Slow progress in introducing electronics into hydraulics
Since the 1990s, Örjan Andrén has tried to introduce more electronics into the hydraulic systems they have been commissioned to build in their consulting role.
– The problem has been that most people in the hydraulics industry come from the mechanical side and do not have much insight into electronics and the advantages it can offer. So it has been slow to introduce more electronics into hydraulic systems, especially in industry. On the mobile side, they were earlier in seeing more of the whole picture and the possibilities electronics can provide, and they are further ahead when it comes to control systems and energy optimization. One possibility that has existed for a long time is to use frequency-controlled electric motors, but industry did not embrace that option until recent years.
– We have offered a course in electric motor system optimization since the 2010s and see that electrification could lead to certain improvements in the design of hydraulic systems, but progress in the industry is slow.
Complexity the toughest challenge in design
On the training side, he does not feel that the prior knowledge of those attending their courses has changed much over the years, not on a general level.
– Of course, within each course group there are major variations, especially in terms of the theoretical background they have. That becomes a bit of a challenge for us as trainers; you have to give them new knowledge based on the level they are at, he explains. When asked what is most difficult about designing a hydraulic system, Örjan Andrén believes it is the complexity of such systems.
– It is a constantly changing system where, for example, the temperature of the oil changes its properties during operation, pressure and flow vary with the load, and much more. That can make it very difficult to calculate the characteristics in order to choose optimal components. Experience is very important. He adds that students often complain that there are no general calculation rules that apply when designing a hydraulic system.
– I can understand that this may feel frustrating. The only rule you really have to relate to is that the system must be safe. Specific rules that can be checked only exist for the accumulators in a hydraulic system. For the other parts, there are machinery directives and harmonized standards to rely on, but you can depart from those if you can provide a good reason.
Always starts by choosing the fluid
In their courses, students learn that the first step in designing a hydraulic system is always to choose the fluid based on the application, which mainly depends on the environment in which the machine operates.
– The hydraulic fluid you choose affects, for example, what types of components can be used in the system, which in turn can affect the sizing of the hydraulic system. The greatest difference is between oil and water as hydraulic fluids. Water is mainly used in dam gates at hydropower plants and locks, and also to some extent in the food industry. When the actual design is then to begin, the greatest challenge is to calculate under what conditions the hydraulic system will operate.
– It is important that the person ordering the system has a good understanding of how it will be used, which they do not always have. They only know that a task is to be carried out, moving something from one place to another. But they do not always know as clearly what forces will affect the system, what friction applies, and so on. However, you need that information before the design of the hydraulic system can begin.
Unnecessarily large safety margins
One aspect of industrial hydraulics that he believes should be developed is the fact that the design often includes very large margins.
– Hydraulic systems could be followed up and optimized much more than they are today. Customers are usually satisfied with getting a system that works and choose not to follow up on performance and collect measurement data that can then be evaluated. If they did, it would be possible afterward to go in and optimize the installed system and thereby save a great deal of energy. He notes, however, that awareness of this possibility is increasing, but there is definitely more to be done.
Trend toward more decentralized systems
A trend in hydraulic system design is that large hydraulic systems are beginning to be divided into several smaller decentralized systems.
– Instead of designing one large system that perhaps controls around 30 different movements, people choose to use several smaller systems that control only a few movements each. Since it is easier to optimize a smaller system, it also becomes easier to optimize the overall solution. Today there are several ready-made box systems that can simply be connected and combined into larger units. An important part of Projekthydraulik’s training concept is that they themselves both hold courses and take on consulting assignments.
– That is our way of continuing to educate ourselves and staying fully informed about how companies work. If you only teach, there is a risk that after a while the courses will be based on outdated knowledge.
