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Large Project in Europe having a Superconducting Magnet

  1. Nov 22, 2005 #1

    Q_Goest

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    I had a customer looking for some equipment that would be used in Europe to cool down a superconducting magnet that was to be installed there possibly in 2006. It must be an exceptionally massive magnet because he's looking for a very large cryogenic compressor and he says it will take 6 months for the magnet to cool down :surprised !!! That's absolutely ENORMOUS!

    What large project could this be? I have to believe it's an experiment that uses massive superconducting magnets on par with the infamous Superconducting Supercollider of the 1980's.
     
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  3. Nov 22, 2005 #2

    FredGarvin

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    Six months to cool down? What the heck retains heat like that? That's not a magnet, that's a coal fire.

    Just between us girls, what kind of flows are we talking here...?
     
  4. Nov 22, 2005 #3

    Danger

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    It's just eosphorus putting together another 'free-energy' contraption.
     
  5. Nov 22, 2005 #4

    Q_Goest

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    Ya know Danger, if it IS a free energy contraption, I'll still be glad to give 'em what they want! 'course, they may blame me for it not workin' then, huh? :confused:

    Hey Fred. Yea, could be a coal fire, but they wouldn't use helium to put that one out. I often wondered if you might put out a coal fire with liquid nitrogen, but not helium. Also wondered why they don't just use N2 in gas chambers (for those death row folks) too, much less expensive and no poison crap to clean up, but that's besides the point... They want 200 lbm/hr flow! And yes, they claim they're cooling down something (I'm assuming a magnet for a bunch of reasons).
     
    Last edited: Nov 22, 2005
  6. Nov 22, 2005 #5

    ZapperZ

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    The only possible candidate for that is the LHC at CERN. They are using superconducting magnets.

    Zz.
     
  7. Nov 22, 2005 #6

    Danger

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    Tokamak reactor? :bugeye:
     
  8. Nov 22, 2005 #7

    Q_Goest

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  9. Nov 23, 2005 #8

    Danger

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    Free energy?! Have you mistaken me for aviator (eosphorus, whatever)?!
    I was unaware of the LHC upgrade, and the only thing that I could think of that could require a magnet of that magnitude (pardon the pun) was a magnetic confinement (Tokamak) fusion reactor.
     
  10. Nov 23, 2005 #9

    vanesch

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    Well, it didn't run before, so it's not exactly an "upgrade" :smile:

    6 months to cool down, on the other hand, seems very long to me...
     
  11. Nov 23, 2005 #10

    FredGarvin

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    Those are the kind of projects that are great to get. Just hope that you get the job and have to oversee the installation. That would be rough.

    Those colliders are pretty awesome pieces of equipment. I always am amazed at what they do and how much it takes to do it.
     
  12. Nov 23, 2005 #11

    Q_Goest

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    Hey Fred, thanks for the well wishes, I hope we get the job too. Unfortunately my only contribution would be as a sub-subcontractor or something like that. I'd only be responsible for the design of a cryogenic helium compressor so unless something goes wrong with it, I don't suppose I'll get a chance to see the LHC or France or any of that neat stuff.

    Hmmm..... maybe I should throw a design flaw in the machine so it only lasts for 3 months... :devil:
     
  13. Nov 23, 2005 #12

    Danger

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    Do you work for Gates?

    Seriously, though... good luck with the contract. If you score big, you'll have to dig up that Tiki Bar thread and buy us a round. :approve:
     
  14. Nov 23, 2005 #13

    Q_Goest

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    Hey Vanesch, just noticed your post, sorry. Yea, I was surprised too. And that's just to get the magnet from ambient to -320 F (78 K), which is the temperature of boiling liquid nitrogen. The cooling of a superconducting magnet is actually pretty interesting, though maybe only a geek would be interested! LOL

    The heat capacity of materials such as copper and stainless is highly skewed as you probably already know. Most of the heat capacity between LHe temp (-452 F or 4 K) and ambient is at the higher temps. By the time you get down to -320, roughly 91% to 94% of the enthalpy is removed. To get to that temp, helium is circulated through the magnet and through a liquid nitrogen heat exchanger. So the helium is cooled to -320 and is then used to remove heat from the magnet. Once the magnet is at -320 they'll probably start dumping truckloads of liquid helium in. About 40% to 50% will boil away before it gets down to temperature and the cryostat (insulated tank the magnet sits in) gets filled. If it's anything like an MRI magnet, and I have to believe it is, then they have to "ramp up" the magnet which means they put current through the windings. A whole lot more liquid helium boils off during this phase. Finally they have to adjust the magnetic field which will take quite a while. I'd guess from the time they start the cool down to the time the facility can actually be used is on the order of 12 months. I suppose we'll have a long wait for that Higgs boson, or whatever they're looking for! <grin>

    Compressor - version 5.2, will be in the works before version 3.0 gets loaded on the ship. As for the Tiki Bar, I'd prefer mine with REAL ice and a tiny umbrella that spins around when you flik it with your finger .... ahhhhhh :)
     
  15. Nov 23, 2005 #14

    ZapperZ

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    I believe the superconducting magnets for LHC were designed and partially built by Brookhaven based on their knowledge of building large superconducting magnets for RHIC. I also don't think they truck in liquid helium. Rather they will have their own refrigeration units for each cooling station within the closed-loop cycle. If not, they'll be gobbling up the world supply of liquid helium.

    Zz.
     
  16. Nov 23, 2005 #15

    Gokul43201

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    I doubt that 6 months is the bare cooldown time. I'm sure there's hundreds of calibration runs and equipment tests that get performed at different temperatures - considering that it's a first-time cooldown.

    A typical, careful cooldown for a dilution fridge can take a few days. For an initial cooldown on a new cryostat, it can take a little longer. If you want to calibrate thermometers and such on the way down, it can take still longer.

    But 6 months is really long. Sounds like the LHC to me too.
     
  17. Nov 25, 2005 #16

    vanesch

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    Normally, each year, there is a winter shutdown - that was the case at least when I was at DESY, where they also have cryogenic magnets for the accelerator. It takes 2 weeks to cool the entire system:

    http://www-kryo.desy.de/documents/softwareKRYK/HERA/abkuehl_e.html

    Now, the LHC is a bigger machine (HERA is 6 km, LHC is 27 km), but the magnets itself will not be so vastly different...
     
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