The use of PM motors in automated processes and production lines is gaining ground globally. This is due to electric motors with permanent magnets offering enhanced performance but with reduced costs, space, maintenance and energy compared to more traditional, asynchronous motors. And the success doesn’t stop there, since PM motors can be optimise even further. Magnet technology plays a crucial role in this; which is precisely why Bakker Magnetics in Science Park Eindhoven is increasingly entering into collaboration with electric-motor developers.
Optimum magnet technology
keeps enhancing PM motors
in process automation
Karl-Josef Gurka | Sales Engineer
“We produce neodymium magnets of all grades and shapes, of world-class quality without exception”
Highly robotised environments, such as a packaging line, without synchronous and linear motors is by now unimaginable. These PM motors provide a very high efficiency rate a high torque, even at fewer revolutions per minute, and compact construction with minimum maintenance requirements. Based on their design principle, PM motors run with the utmost speed and precision, making them ideal for today’s exacting automated processes and production lines.
PM-motor manufacturers are constantly seeking out ways to make their motors’ already high degree of efficiency and sustainability, with magnet assembly being intrinsic to motors. For servo motors, magnets are fastened to a rotor-bearing system.
“Magnet-technology optimisation delivers enhanced motor performance from the outset“
For linear drives, the magnets are arranged in a line. ‘Magnet-technology optimisation delivers enhanced motor performance from the outset’, says Karl-Josef Gurka, Sales Engineer Projects and Account Manager at Bakker Magnetics, with years of experience in the process automation market under his belt. ‘A whole range of aspects determine how a magnet assembly functions. The grade of the magnet material, obviously; but also the magnet dimensions, their setup, the angle accuracy, coatings and adhesion. This all has a significant effect on PM motor’s performance and operational reliability. This is why engaging specialists services at as early a stage as possible is wise.’
Manufacturer and System Partner
Bakker Magnetics entered into a joint venture with one of China’s largest and most advanced magnet factories, for supplying separate magnets to PM motor manufacturers. According to Karl-Josef: ‘At that site we produce neodymium magnets of all grades and shapes, of world-class quality without exception. The highest energy density and temperature resistance are no problem for us. Moreover, we ensure that magnets supplied from China to Bakker in the Netherlands are inspected in our quality laboratory. For Bakker Magnetics, delivering separate magnets and the supply-chain role the company can fulfil for clients is a major cornerstone. Nevertheless, according to Karl-Josef, Bakker truly excels as a system partner: developing and producing complex magnet assemblies. ‘Designing and producing the magnet system in consultation with the customer means we can make a real difference..’
“50 years of knowledge and experience
give our clients the lead”
Focus on Application
As a magnet-assemblies system partner, Bakker has a range of options for determining an assembly’s feature from the very outset, despite design optimisation in fact starting from the end: with the application. According to Karl-Josef: ‘From word go, the focus is on the application. Under what conditions will the PM motor be used? Does this entail moisture, salt, heat, mechanical load or vibrations? The motor manufacturer obviously has its own conditions and characteristics where operational temperature, performance and design are concerned. As a specialist, we see to it that the magnet assembly is fully optimised for the motor it runs in and the motor’s intended application. In other words, the very best magnet system, and therefore optimal motor performance. Our client expect precisely what we offer: engineering coupled with production.’
To supply the highest quality magnets and assemblies, both current and long term, Bakker Magnetics has been striving to improve materials and technologies, in China and the Netherlands, for over 50 years. According to Karl-Josef, the latest innovations include ‘Alongside our Chinese joint venture partner, we developed a new passivation for neodymium magnets, resulting in a high adhesive strength and glue adhesion between the rotor bearing system and magnet. This passivation means uncoated neodymium magnets have extremely high adhesion properties with a shear strength of no less than 15-20 N mm². Wrapping is no longer required, even at 10,000 rpm. What’s more, the uncoated passivated magnets have excellent corrosion stability due to an improved production process and incorporating metal additives. A 96-hour HAST test under 2.6 bars of pressure and a 95% relative air humidity revealed the magnet suffers minimal material loss; less than 3 mg per cm2. An exceptional result, meaning that even in a humid climate, our non-coated passivated magnets with extreme adhesion strength meet all expectations. We can provide also a High Performance Coating with 700-1000 hours of SST resistance, if higher corrosion protection is required. And for automated processes in extreme temperatures, we can supply AH and BH neodymium magnets with grades withstanding up to 220°C and 240°C.’
Smart Magnetic Engineering
PM motors with optimum magnet assemblies respond in full to the high demands of the automated Industry 4.0 processes and production lines. In this day and age, PM electric-motor manufacturers and their customers expect nothing less than optimised quality. According to Karl-Josef: ‘This is not a standard products market. Sharing our thoughts and ideas is a win-win for everyone, and best from day one. First consider the application. Then calculate everything required: grades, dimensions, coatings, temperatures, adhesion and other features. And then develop, test and produce the best possible assembly. It never ceases to be a wonderful challenge. It’s also a real pleasure hearing clients telling us they enjoyed working with us, because we’re so approachable and flexible in the process. Besides innovations, the most significant reason why our magnet technology continuously improves PM motors in process automation might be that we can’t do it alone, but together. We call it: Smart Magnetic Engineering. By Bakker Magnetics,’ concludes Karl-Josef.