Apparatus and method for maintaining low temperatures about an object at a remote location

• US 4,340,405 A
• Filed: 10/29/1980
• Issued: 07/20/1982
• Est. Priority Date: 10/29/1980
• Status: Expired due to Term

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: United States Department of Energy (Government of the United States of America)
• Inventors: Overton, William C. Jr., Steyert, William A. Jr.
• Primary Examiner(s): Capossela, Ronald C.
• Application Number:
  US06/202,041
• Time in Patent Office: 629 Days
• Field of Search: 62/514 R, 62/437, 62/62, 62/45, 62/383, 165/80 E, 165/185
• US Class Current: 62/51.1
• CPC Class Codes: F25D 3/00 Devices using other cold materials; Devices using cold-storage bodies
• CPC Class Codes: F25D 3/10 using liquefied gases, e.g. liquid air for cooling semiconductor devices H01L23/445
• CPC Class Codes: G01V 3/18 specially adapted for well-logging
• CPC Class Codes: G12B 15/00 Cooling by refrigeration, e.g. circulation of refrigerated fluid, F25D; heat-exchange or heat-transfer details of general application F28F
• CPC Class Codes: Y10S 505/889 Utilizing rare earth material

Abstract

The disclosure is directed to an apparatus and method for maintaining a body at cryogenic temperatures at a remote location such as down a borehole for an extended period of time. A housing contains a body comprising a material having a high specific heat at cryogenic temperatures such as between about 2 and 15 K. The body contains an orifice for containing an instrument or instruments operable at superconducting temperatures. The apparatus is precooled at the surface and lowered into a borehole to a desired depth, such as 2 to 3 miles. The instruments are operated, and the apparatus withdrawn, the material of the body maintaining the very low temperatures at which the instrument(s) operate for a sufficient period of time at the remote or downhole location. The material may comprise a rare earth compound, such as Gd₂ O₃, Gd₂ Se₃, Gd₂ O₂ S or GdAlO₃. Monoclinic and C-phase gadolinium oxides work well. A low temperature is maintainable at a remote location for several hours.

Claims

1. An apparatus for maintaining cryogenic temperatures about an object for an extended period of time in a remote location comprising:

a housing;

a body comprising a material having a high specific heat at cryogenic temperatures disposed within said housing, said body comprising an orifice for receiving said object; and

means for conducting cryogenic coolant to said body to lower its temperature to at least about 2 to about 15 K.

2. The invention of claim 1 further comprising a layer of superinsulation disposed between said housing and said body.

3. The invention of claim 1 wherein said body comprises a rare earth material.

4. The invention of claim 1 wherein said body comprises a gadolinium compound.

5. The invention of claim 1 wherein said body comprises monoclinic gadolinium oxide.

6. The invention of claim 1 wherein said body comprises C-phase gadolinium oxide.

7. The invention of claim 1 wherein said body comprises a compound selected from the group consisting of Gd₂ O₃, Gd₂ Se₃, Gd₂ O₂ S and GdAlO₃.

8. The invention of claim 1 wherein said body comprises fused Gd₂ O₃.

9. The invention of claim 1 wherein said cryogenic coolant conducting means comprises a conduit for a liquid gas disposed within said body, means for passing liquid gas through said housing into said conduit and means for venting said conduit.

10. The invention of claim 1 wherein said liquid gas comprises liquid helium.

11. The invention of claim 1 wherein said housing is at least partially lineable with ice.

12. The invention of claim 1 wherein said housing is substantially lined with aluminized superinsulation.

13. The invention of claim 1 wherein said housing comprises a pressure vessel.