Magnetic coupling at elevated temperatures

Magnetic couplings are utilized in many applications inside pump, chemical, pharmaceutical, course of and security industries. They are sometimes used with the aim of lowering put on, sealing of liquids from the surroundings, cleanliness needs or as a safety factor to brake over if torque suddenly rises.
The most common magnetic couplings are made with an outer and internal drive, both build up with Neodymium magnets to find a way to get the highest torque density as possible. By optimizing the diameter, air hole, magnet dimension, number of poles and choice of magnet grade, it’s attainable to design a magnetic coupling that suits any application in the vary from few millinewton meter up to a number of hundred newton meters.
When only optimizing for prime torque, the designers often are likely to forget considering the influence of temperature. If the designer refers again to the Curie level of the individual magnets, he’ll claim that a Neodymium magnet would fulfill the requirements up to greater than 300°C. Concurrently, it could be very important embrace the temperature dependencies on the remanence, which is seen as a reversible loss – typically round 0,11% per diploma Celsius the temperature rises.
Furthermore, a neodymium magnet is beneath pressure during operation of the magnetic coupling. This means that irreversible demagnetization will happen lengthy earlier than the Curie level has been reached, which typically limits the use of Neodymium-based magnetic coupling to temperatures under 150°C.
If larger temperatures are required, magnetic couplings made from Samarium Cobalt magnets (SmCo) are usually used. เกจวัดแรงดันน้ำมันเบนซิน is not as sturdy as Neodymium magnets however can work as a lot as 350°C. Furthermore, the temperature coefficient of SmCo is just zero,04% per diploma Celsius which signifies that it might be utilized in functions where performance stability is needed over a larger temperature interval.
New generation In collaboration with Copenhagen Atomics, Alfa Laval, Aalborg CSP and the Technical University of Denmark a brand new era of magnetic couplings has been developed by Sintex with support from the Danish Innovation Foundation.
The objective of the venture was to develop a magnetic coupling that might increase the working temperature area to reach temperatures of molten salts round 600°C. By exchanging the inside drive with a magnetic materials containing a better Curie level and boosting the magnetic area of the outer drive with particular magnetic designs; it was potential to develop a magnetic coupling that began at a lower torque level at room temperature, but solely had a minor discount in torque level as a function of temperature. This resulted in superior performance above 160°C, irrespective of if the benchmark was against a Neodymium- or Samarium Cobalt-based system. This may be seen in Figure 1, where it is shown that the torque degree of the High Hot drives has been examined as much as 590°C on the inner drive and still carried out with an virtually 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 decrease temperature market where performance stability is important over a bigger temperature interval.
Conclusion At Sintex, the R&D department remains to be growing on the expertise, however they have to be challenged on torque degree at both completely different temperature, dimensions of the magnetic coupling or new purposes that have not beforehand been attainable with normal magnetic couplings, to find a way to harvest the complete potential of the High Hot technology.
The High Hot coupling just isn’t seen as a standardized shelf product, however instead as custom-built by which is optimized for particular applications. Therefore, additional improvement shall be made in shut collaboration with new companions.

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