Cryogen Free Magnet Systems

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Cryogen Free Magnet Systems
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Background

• Cryogenic Ltd is a pioneer of Cryogen Free magnet
  systems.
• Prior to this development high magnetic fields
  were only available to those with access to
  liquid helium.
• Alternatives such as water cooled electromagnets
  require very large power units.
• The cryogen free technology allows magnets of a
  wide range of fields and dimensions to be built
  using the same method of refrigeration.

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Technical Infrastructure
The Basic system includes The superconducting
magnet up to 18 Tesla An integrated VTI built
into the bore of the CFM providing temperatures
in the range of 1.6K to 325K Cryocooler and
compressor to simultaniously cool both the VTI
and the magnet. Electronics Rack housing the
bipolar magnet power supply, temperature
controller, scanner and the measurement option
electronics. The computer (Pentium based with
high resolution TFT screen), including all
software, additional Keithly instruments, I/O,
IEEE and other necessary cards for
measurements. LabVIEW operating software with
development package and software.
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Cooling MethodGifford McMahon vs Pulse Tube
The GM cryocooler has the advantage of greater
thermodynamic efficiency and reliable operation
in any orientation The PT cooler is quieter and
has a longer service intervals with low servicing
costs. Both can provide up to 1.5 wattts of
cooling power at 4K and more than 50W on the 60K
stage. Cooling down from start-up to operating
temperature takes typcially 24 to 48 hours
depending on the size of the magnet.
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Operating Benefits
Low operating costs. No liquid helium or
nitrogen required for cool-down or operation. No
costs associated with storage and transport of
liquids. Simple to use Switch on the cooler and
wait for it to reach operating temperature. The
system is then ready to use. Independent and
convenient Since only mains electric power is
required to operate the system, it can be used
anywhere. Compact The absence of liquids means
that the CFMs are more compact with easy to
access field centre. Dry system There is no
liquid helium surrounding the magnet to cause
leakage or maintenance problem.
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Orientation Can be operated in any orientation.
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Cryogen Free Magnet with Integrated VTI
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Cryogen Free Magnet with Integrated VTI
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Automation

• The system is installed with the National
  Instruments.
• LabVIEW operating software and a standard
  Cryogenic applications package, which allows the
  complete system to be run under computer control.
  
• This allows 
• Control of magnetic field
• Fail-safe shutdown even with power failure.
• Better data presentation, real data and then
  curve fitted data.
• Full development software licence allowing the
  user to develop special applications

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Photos of delivered Cryogen Free systems
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• 10 Coil Cryogen Free Magnet System Utilising Dual
  Cryocoolers.
• Enclosed in Stainless Steel cryostat appropriate
  for UHV of 10-9 mbar.

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• 6 Tesla split pair magnet.
• Cryogen Free UHV cryostat.
• Radial split of 50mm for optimised optical
  access.
• 4 radial access ports at 90 degrees and 8 7
  radial access ports at 45 degrees.
• Used for electron beam ion traps to be developed
  at the Max-Planck Institute for Nuclear Physics.

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VSM to 18 Tesla
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Desktop Cryogen Free Magnet
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Cryogen Free Neutron Scattering and Beam-line
Magnets
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Cryogen Free Neutron Scattering and Beam-line
Magnets
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Cryogen Free Neutron Scattering and Beam-line
Magnets
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Cryogen Free Optimag Systems
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ESR Magnets
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Rotating Sample Probe
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Optical Cryostat
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Radiometer
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Large Bore Magnets5 Tesla 400mm bore
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Variable Temperature Insert