I may be able to provide you with some ideas to assist you with the
installation of cryoprobes. I recently installed a cryoprobe in my lab
and therefore, faced many of the same issues.
Placement of the Helium Compressor - I was unable to find suitable space
far away from my work area so instead my compressor is about 3.5 feet
from my shielded 500MHz magnet. I have enclosed it in a box that is
equipped with sound proofing material. The box is somewhat large (a
foot print of 3ft by 4.5ft to allow manufacturer suggested distances for
ventilation) but it completely eliminates the noise from the helium
compressor. The compressor is cooled by recycled water from a
recirculating water chiller. There are no vents in the box other than
the hole that all the plumbing, transferlines and cables runs through.
The temperature in the box although warm has not been a problem.
I actually find the location of my compressor preferable because with
the noise from the helium compressor eliminated I noticed that the
helium tranfer lines from the compressor to the cryocooling unit do
produce some noise. Because of the close proximity of my compressor to
my cryocooling unit (~4 feet)I was able to reduce the noise from the
transferlines by placing a sound proofing box over the coiled
transferlines.
The chiller that we use was placed in the back of the building ~200 feet
away. It is of sufficient capacity to run 2 cryoplatforms and two x-ray
diffractometers. We went with the closed water chiller rather than the
air cooled radiator because the water chiller will be more efficient
during summer temperatures and our existing air conditioning could not
handle any more of a heat load.
I hope this information helps. Please contact me if you need further
details on what I have done here to install my cryoprobe.
Best Regards,
Kim Colson
*********************************************
Kimberly L. Colson, Ph.D.
Applications Scientist - NMR Spectroscopy
Bruker Instruments, Inc.
15 Fortune Drive
Manning Park
Billerica, MA 01821
Phone: (978) 667-9580, Ext. 114
FAX: (978) 667-2955
email: kim.colson@nmr.bruker.com
Application Support Hotline
Phone: (978) 667-9580, Ext. 444
FAX: (978) 667-2955
email: applab@nmr.bruker.com
*********************************************
> -------- Original Message --------
> Subject: First experiences with cryoprobes ?
> Date: Wed, 8 Sep 1999 17:55:04 -0400
> From: Rainer Haessner <Rainer.Haessner@bigfoot.de>
> To: ammrl@wwitch.unl.edu
>
> Hi, AMMRL members,
>
> with a high probability we will get some cryoprobes (presumable 3)
> within the
> couple of the next year.
> Now I have to solve the technical problems to install these devices.
> There is one main problem:
> where shall I install the compressors?
> To my informations one of the compressors needs 9 kW of electrical
> power.
> That's why I have a problems concerning the heat production.
> Of course, I believe, it's helpful to discuss all of the problems with
> the
> specialists in Faellanden and of course I will do this next time.
> Nevertheless there could be some good ideas here. Maybe others have
> comparable problems and we could ask the developers to introduce
> some changes into the concept.
>
> So please allow to come back to the primary problem: a convenient place
> for the compressors. An ideal place to install the compressors would
> be available in a distance of about 70 meters from the spectrometers.
> Even more, there exists a system of helium tubes within the building
> (70 mm id), which could be used for the transport of the normal
> pressured helium. The specialists say: too long.
> The above mentioned location furthermore allows an autarc cooling of
> the compressors. In the case of all other possible locations I need
> water cooling (no room is able to remove 9 kW by air cooling).
> We have a closed water cooling circuit within the building, but the
> capacity of this circuit is about only 540 kW for the whole building.
> Even more, for about 10 days in the summer the capacity of this
> water cooling circuit is insufficient (without the compressors).
>
> That are my first thoughts and of course they are somewhat fragmented.
> Now I am looking for other ideas or even better experiences.
>
> Best regards
>
> Rainer Haessner