Ultra high vacuum pumping system and high sensitivity helium leak detector

Myneni, G R

Title: Ultra high vacuum pumping system and high sensitivity helium leak detector

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Abstract

An improved helium leak detection method and apparatus are disclosed which increase the leak detection sensitivity to 10{sup {minus}13} atm cc/s. The leak detection sensitivity is improved over conventional leak detectors by completely eliminating the use of o-rings, equipping the system with oil-free pumping systems, and by introducing measured flows of nitrogen at the entrances of both the turbo pump and backing pump to keep the system free of helium background. The addition of dry nitrogen flows to the system reduces back streaming of atmospheric helium through the pumping system as a result of the limited compression ratios of the pumps for helium. 2 figs.

Inventors:: Myneni, G R

Issue Date:: 1997-12-30

Research Org.:: Southeastern University Research Association

Sponsoring Org.:: USDOE, Washington, DC (United States)

OSTI Identifier:: 563640

Patent Number(s):: 5703281

Application Number:: PAN: 8-646,773; TRN: 98:002115

Assignee:: Southeastern Univ. Research Association, Newport News, VA (United States)

DOE Contract Number:: AC05-84ER40150

Resource Type:: Patent

Resource Relation:: Other Information: PBD: 30 Dec 1997

Country of Publication:: United States

Language:: English

Subject:: 44 INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; 43 PARTICLE ACCELERATORS; LEAK DETECTORS; HELIUM; VACUUM SYSTEMS; PERFORMANCE; NITROGEN; DESIGN; OPERATION; CEBAF ACCELERATOR

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                    Myneni, G R. Ultra high vacuum pumping system and high sensitivity helium leak detector.  United States: N. p., 1997. 
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                    Myneni, G R. Ultra high vacuum pumping system and high sensitivity helium leak detector.  United States.

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        "Ultra high vacuum pumping system and high sensitivity helium leak detector".  United States.

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@article{osti_563640,

  title        = {Ultra high vacuum pumping system and high sensitivity helium leak detector},

  author       = {Myneni, G R},

  abstractNote = {An improved helium leak detection method and apparatus are disclosed which increase the leak detection sensitivity to 10{sup {minus}13} atm cc/s. The leak detection sensitivity is improved over conventional leak detectors by completely eliminating the use of o-rings, equipping the system with oil-free pumping systems, and by introducing measured flows of nitrogen at the entrances of both the turbo pump and backing pump to keep the system free of helium background. The addition of dry nitrogen flows to the system reduces back streaming of atmospheric helium through the pumping system as a result of the limited compression ratios of the pumps for helium. 2 figs.},

  doi          = {},

  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1997},

  month        = {12}

}

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