Magnetic coupling at elevated temperatures

Magnetic couplings are utilized in many purposes within pump, chemical, pharmaceutical, course of and safety industries. They are sometimes used with the purpose of decreasing put on, sealing of liquids from the surroundings, cleanliness wants or as a safety issue to brake over if torque all of a sudden rises.
The most typical magnetic couplings are made with an outer and internal drive, both build up with Neodymium magnets to have the ability to get the best torque density as potential. By optimizing the diameter, air gap, magnet measurement, number of poles and selection of magnet grade, it’s potential to design a magnetic coupling that suits any application in the vary from few millinewton meter as a lot as a number of hundred newton meters.
When solely optimizing for prime torque, the designers often tend to overlook considering the influence of temperature. If the designer refers to the Curie point of the person magnets, he will declare that a Neodymium magnet would fulfill the requirements as a lot as more than 300°C. Concurrently, it is very important embody the temperature dependencies on the remanence, which is seen as a reversible loss – usually around zero,11% per degree Celsius the temperature rises.
Furthermore, a neodymium magnet is beneath strain during operation of the magnetic coupling. This signifies that irreversible demagnetization will occur long before the Curie level has been reached, which typically limits the use of Neodymium-based magnetic coupling to temperatures under 150°C.
If higher temperatures are required, magnetic couplings manufactured from Samarium Cobalt magnets (SmCo) are typically used. SmCo is not as sturdy as Neodymium magnets however can work up to 350°C. Furthermore, the temperature coefficient of SmCo is only zero,04% per diploma Celsius which signifies that it might be used in functions where performance stability is needed over a larger temperature interval.
New technology In collaboration with Copenhagen Atomics, Alfa Laval, Aalborg CSP and the Technical University of Denmark a brand new generation of magnetic couplings has been developed by Sintex with assist from the Danish Innovation Foundation.
The function of the venture was to develop a magnetic coupling that would broaden the working temperature space to achieve temperatures of molten salts around 600°C. By exchanging เกจวัดแรงดันลมราคา with a magnetic material containing the next Curie level and boosting the magnetic subject of the outer drive with particular magnetic designs; it was possible to develop a magnetic coupling that began at a lower torque degree at room temperature, however solely had a minor discount in torque degree as a perform of temperature. This resulted in superior efficiency above 160°C, regardless of if the benchmark was in opposition to a Neodymium- or Samarium Cobalt-based system. This may be seen in Figure 1, where it’s proven that the torque degree of the High Hot drives has been tested up to 590°C on the inside drive and still performed with an virtually linear discount in torque.
The graph additionally exhibits that the temperature coefficient of the High Hot coupling is even decrease than for the SmCo-system, which opens a decrease temperature market where performance stability is important over a larger temperature interval.
Conclusion At Sintex, the R&D division continues to be growing on the expertise, however they have to be challenged on torque stage at either completely different temperature, dimensions of the magnetic coupling or new purposes that haven’t beforehand been potential with standard magnetic couplings, in order to harvest the total potential of the High Hot know-how.
The High Hot coupling is not seen as a standardized shelf product, but as an alternative as custom-built by which is optimized for specific applications. Therefore, further growth might be made in shut collaboration with new partners.

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