Magnetic couplings are utilized in many functions inside pump, chemical, pharmaceutical, process and security industries. They are usually used with the aim of decreasing wear, sealing of liquids from the setting, cleanliness wants or as a security factor to brake over if torque all of a sudden rises.
The commonest magnetic couplings are made with an outer and inside drive, both construct up with Neodymium magnets so as to get the highest torque density as potential. By optimizing the diameter, air hole, magnet dimension, number of poles and selection of magnet grade, it is attainable to design a magnetic coupling that suits any application within the vary from few millinewton meter as a lot as several hundred newton meters.
When solely optimizing for top torque, the designers often are most likely to overlook contemplating the influence of temperature. If the designer refers back to the Curie level of the individual magnets, he’ll declare that a Neodymium magnet would fulfill the requirements up to greater than 300°C. Concurrently, it may be very important embrace the temperature dependencies on the remanence, which is seen as a reversible loss – usually around 0,11% per diploma Celsius the temperature rises.
Furthermore, a neodymium magnet is under pressure during operation of the magnetic coupling. This implies that irreversible demagnetization will happen lengthy before the Curie level has been reached, which typically limits the usage of Neodymium-based magnetic coupling to temperatures below 150°C.
If higher temperatures are required, magnetic couplings made of Samarium Cobalt magnets (SmCo) are typically used. SmCo is not as robust as Neodymium magnets but can work up to 350°C. Furthermore, the temperature coefficient of SmCo is simply zero,04% per degree Celsius which implies that it may be utilized in functions the place performance stability is needed over a bigger temperature interval.
New generation In collaboration with Copenhagen Atomics, Alfa Laval, Aalborg CSP and the Technical University of Denmark a new technology of magnetic couplings has been developed by Sintex with support from the Danish Innovation Foundation.
เกจวัดแรงดันออกซิเจน of the project was to develop a magnetic coupling that could broaden the working temperature area to reach temperatures of molten salts around 600°C. By exchanging the inside drive with a magnetic materials containing the next Curie level and boosting the magnetic area of the outer drive with particular magnetic designs; it was potential to develop a magnetic coupling that started at a decrease torque degree at room temperature, however solely had a minor reduction in torque degree as a operate of temperature. This resulted in superior efficiency above 160°C, no matter if the benchmark was towards a Neodymium- or Samarium Cobalt-based system. This could be seen in Figure 1, where it’s proven that the torque stage of the High Hot drives has been tested as a lot as 590°C on the internal drive and nonetheless performed with an almost linear reduction in torque.
The graph also shows that the temperature coefficient of the High Hot coupling is even decrease than for the SmCo-system, which opens a lower temperature market where efficiency stability is essential over a larger temperature interval.
Conclusion At Sintex, the R&D division remains to be developing on the technology, however they must be challenged on torque degree at both different temperature, dimensions of the magnetic coupling or new applications that have not previously been attainable with standard magnetic couplings, so as to harvest the complete potential of the High Hot expertise.
The High Hot coupling just isn’t seen as a standardized shelf product, but instead as custom-built by which is optimized for particular purposes. Therefore, further growth might be made in close collaboration with new partners.
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