Back to results
US 4,484,458 AGranted
Apparatus for condensing liquid cryogen boil-off
AssigneeAir Products and Chemicals, Inc.
InventorRalph C. Longsworth
Life of this patent
Estimating the term…
Abstract
An apparatus for condensing cryogen (e.g., helium) boil-off in a confined space such as the neck tube of a helium cryostat comprising a Joule-Thompson heat exchanger and valve disposed around a displacer-expander cryogenic refrigerator so the thermal gradient in the heat exchanger matches that of the refrigerator.
Claims8
An apparatus for condensing liquid cryogen boil-off in a confined space comprising in combination:
- a multi-stage displacer-expander refrigerator with each stage of said refrigerator containing a heat station, said refrigerator having a coldest stage capable of being cooled to between 15.degree. and 20.degree. K.;
- a helium recondenser disposed axially and spaced apart from the coldest stage of said refrigerator;
- a Joule-Thompson heat exchanger coiled around said refrigerator and in thermal contact with each of said heat stations, said heat exchanger constructed and arranged to conduct high pressure helium to a Joule-Thompson valve disposed upstream of said helium recondenser and return low pressure helium, said Joule-Thompson heat exchanger adapted to approximately match thermal gradients in said refrigerator and in the stratified helium between the coldest stage of said refrigerator and said helium condenser.
Dependencies are inferred from the claim text.