Liquid Helium Superconducting Magnet
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Liquid Helium Variable Temperature Research Dewars
CRYO Variable Temperature Liquid Helium Research Dewars CRYO Variable Temperature Liquid Helium Research Dewars Cryo Industries Variable Temperature Liquid Helium Research Dewars (CN Series) provide soluitions for an extensive variety of low temperature optical and non-optical requirements. There are numerous designs available, including Sample in Flowing Vapor, Sample in Vacuum and Sample in Exchange Gas. Our most popular models features Sample in Flowing Vapor (dynamic exchange gas), where the sample is cooled by insertion into flowing helium gas exiting from the vaporizer (also known as the diffuser or heat exchanger). The samples are top loading and can be quickly changed while operating. The temperature of the sample can be varied from typically less than 1.4 K to room temperature. Liquid helium flows from the reservoir through the adjustable flow valve down to the vaporizer located at the bottom of the sample tube. Applying heat, vaporizes the liquid and raises the gas temperature. This gas enters the sample zone to cool the sample to your selected temperature. Pumping on the sample zone will provide temperatures below 2 K with either sample in vapor or immersed in liquid. No inefficient liquid helium reservoir pumping is required. The system uses enthalpy (heat capacity) of the helium vapor which results in very high power handling, fast temperature change, ultra stable temperatures, ease of use an much more - Super Variable Temperature. Optical ‘cold’ windows are normally epoxy sealed, strain relief mounted into indium sealed mounts or direct indium mounted. Window seals are reliable and fully guaranteed. For experiments where flowing vapor may be undesirable (such as mossbauer or infrared detectors), static exchange gas cooling and sample in vacuum inserts are available. -
Introduction to Cryostat Design
Introduction to Cryostat Design J. G. Weisend II July 2014 Course Goals Provide an introduction to cryostat design Examine cryostats as integrated systems rather then a group of subsystems Provide background information and useful data Provide pointers to resources for more detail Show examples Introduction to Cryostat Design 7/7/14 2 J. G. Weisend II ICEC 2014 Syllabus Introduction Cryostat Requirements Materials Selection Thermal Isolation and Heat Leak Structures Safety Instrumentation Seals, Feed throughs and Bayonets Transfer Lines Examples References and Resources Introduction to Cryostat Design 7/7/14 3 J. G. Weisend II ICEC 2014 Introduction What is a cryostat? A device or system for maintaining objects at cryogenic temperatures. Cryostats whose principal function is to store cryogenic fluids are frequently called Dewars. Named after the inventor of the vacuum flask and the first person to liquefy hydrogen Introduction to Cryostat Design 7/7/14 4 J. G. Weisend II ICEC 2014 Introduction Cryostats are one of the technical building blocks of cryogenics There are many different types of cryostats with differing requirements The basic principles of cryostat design remain the same Before we can do anything else we have to define our requirements Introduction to Cryostat Design 7/7/14 5 J. G. Weisend II ICEC 2014 E158 LH2 Target Cryostat Introduction to Cryostat Design 7/7/14 6 J. G. Weisend II ICEC 2014 Cryostat Requirements Maximum allowable heat leak at various temperature levels This may be driven by the number of cryostats to be built as well as by the impact of large dynamic heat loads (SCRF or target cryostats) Alignment and vibration requirements Impact of thermal cycles Need to adjust alignment when cold or under vacuum? Alignment tolerances can be quite tight (TESLA : +/‐ 0.5 mm for cavities and +/‐ 0.3 mm for SC magnets) Introduction to Cryostat Design 7/7/14 7 J. -
Versatile Cryogen-Free Cryostat for the Electromagnetic Characterization Of
Saniour et al. EPJ Techniques and Instrumentation (2020) 7:3 EPJ Techniques and https://doi.org/10.1140/epjti/s40485-020-00055-2 Instrumentation RESEARCH ARTICLE Open Access Versatile cryogen-free cryostat for the electromagnetic characterization of superconducting radiofrequency coils Isabelle Saniour1*† , Michel Geahel1,2,3†, Javier Briatico2, Cornelis J. van der Beek3,4, Georges Willoquet1, Laurène Jourdain1, Bertrand Baudouy5, Gilles Authelet5, Jean-Christophe Ginefri1, Luc Darrasse1 and Marie Poirier-Quinot1 * Correspondence: isabelle.saniour@ universite-paris-saclay.fr Abstract Isabelle Saniour and Michel Geahel are Co-first authors. The use of high temperature superconducting (HTS) radio frequency (RF) coils in †Isabelle Saniour and Michel Geahel Magnetic Resonance Imaging (MRI) greatly improves the signal-to-noise ratio (SNR) contributed equally to this work. in many biomedical applications and particularly in micro-MRI. However, a detailed 1Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Orsay, France understanding of the electrical behavior of HTS coils is important in order to Full list of author information is optimize their performance through MR experiments. This paper presents a simple available at the end of the article and versatile cryogen-free cryostat designed to characterize the RF properties of HTS coils prior to their use in MRI. The cryostat can be used at temperatures from 50 K to 300 K, with a control precision of approximately 3 mK at 70 K, and can measure the RF electrical power transmitted to an HTS coil over a range from 1 μW to 10 W. The quality factor and resonance frequency of the tested HTS coil are determined as a function of the temperature and the power it dissipates. -
New Target Cryostat for Experiments with Negative Muons
! XJ9900001 OBbEflMHEHHbM MHCTMTYT flflEPHbIX MCCJlEflOBAHMM flyoHa D13-98-146 V.F.Boreiko, V.M.Bystritsky, V.I.Datskov, A.N.Fedorov, V.N.Pavlov, V.A.Stolupin, A.Del Rosso1, R.Jacot-Guillarmod1, F.Mulhauser1, L.A.Rivkis2 NEW TARGET CRYOSTAT FOR EXPERIMENTS WITH NEGATIVE MUONS Submitted to «Nuclear Instruments and Methods* 'institute of Physics, University of Fribourg, Switzerland 2A.A.Bochvar All-Russia Research Institute of Inorganic Materials, Moscow, Russia 30-07 1998 Introduction The study of processes yielding charge nonsymmetric muonic molecules like pxZ (z = p,d,t and Z = He, Li, Be) and nuclear fusion started about fifteen years ago. Theoretical and experimental interest have increased these past five years [1-13]. Due to some experimental difficulties, the muon catalyzed fusion (pCF ) is essentially measured in deuterium-helium mixtures. The nuclear fusion from the charge nonsymmetric molecule pd 3He may occur via two different channels, pd3He -4 a + p(14.7 MeV) + p (1) -4 psLi +7(16.4 MeV), (2) whereas the pd4He molecule fuses via a single channel pd*He -4 p6U + 7(1.48 MeV). (3) The proposed apparatus should be able to easily detect those fusion products. In addition, the 6.85 keV soft X rays resulting form the decay of the pd4He and pd3He molecules should be measured, as well as the muon decay electrons. The detection of so many different types of particles, with totally different paths in matter, is a non-trivial constraint in the design of the apparatus. The different processes which occur when a muon enters a deuterium-helium mix ture are strongly dependent on the mixture density. -
Liquid Helium
Safetygram 22 Liquid helium Liquid helium is inert, colorless, odorless, noncorrosive, extremely cold, and nonflammable. Helium will not react with other elements or compounds under ordinary conditions. Since helium is noncorrosive, special materials of construction are not required. However, materials must be suitable for use at the extremely low temperatures of liquid helium. Vessels and piping must be selected and designed to withstand the pressure and temperatures involved and comply with applicable codes for transport and use. Manufacture Most of commercial helium is recovered from natural gas through a cryogenic separation process. Normally, helium is present in less than 1% by volume in natural gas. Helium is recovered, refined, and liquefied. Liquid helium is typically shipped from production sources to storage and transfill facilities. Tankers, ranging in size from 5,000 to 11,000 gallons, contain an annular space insulated with vacuum, nitrogen shielding, and multilayer insulation. This de- sign reduces heat leak and vaporization of liquid helium during transportation. Uses The extremely low temperature of liquid helium is utilized to maintain the superconducting properties of magnets in applications such as MRI, NMR spectroscopy, and particle physics research. The main application for gas- eous helium is for inert shielding gas in metal arc and laser welding. Helium provides a protective atmosphere in the production of reactive metals, such as titanium and zirconium. Gaseous helium is used as a coolant during the draw- ing of optical fibers, as a carrier gas for chromatography, and as a leak detection gas in a variety of industries. Being both lighter than air and nonflammable, helium is used to inflate balloons and airships. -
Helium, Refrigerated Liquid
Helium, Refrigerated Liquid Safety Data Sheet P-4600 This SDS conforms to U.S. Code of Federal Regulations 29 CFR 1910.1200, Hazard Communication. Issue date: 01/01/1979 Revision date: 01/31/2021 Supersedes: 09/08/2020 Version: 2.0 SECTION: 1. Product and company identification 1.1. Product identifier Product form : Substance Trade name : Liquid Helium CAS-No. : 7440-59-7 Formula : He Other means of identification : Helium, Refrigerated Liquid; Helium-4; Refrigerant Gas R-704 1.2. Relevant identified uses of the substance or mixture and uses advised against Use of the substance/mixture : Industrial use; Use as directed. Diving Gas (Underwater Breathing) 1.3. Details of the supplier of the safety data sheet Linde Inc. 10 Riverview Drive Danbury, CT 06810-6268 - USA 1.4. Emergency telephone number Emergency number : Onsite Emergency: 1-800-645-4633 CHEMTREC, 24hr/day 7days/week — Within USA: 1-800-424-9300, Outside USA: 001-703-527-3887 (collect calls accepted, Contract 17729) SECTION 2: Hazard identification 2.1. Classification of the substance or mixture GHS US classification Simple asphyxiant SIAS Press. Gas (Ref. Liq.) H281 2.2. Label elements GHS US labeling Hazard pictograms (GHS US) : GHS04 Signal word (GHS US) : Warning Hazard statements (GHS US) : H281 - CONTAINS REFRIGERATED GAS; MAY CAUSE CRYOGENIC BURNS OR INJURY OSHA-H01 - MAY DISPLACE OXYGEN AND CAUSE RAPID SUFFOCATION. Precautionary statements (GHS US) : P202 - Do not handle until all safety precautions have been read and understood. P271+P403 - Use and store only outdoors or in a well-ventilated place. P282 - Wear cold insulating gloves/face shield/eye protection. -
Visualization of Two-Fluid Flows of Superfluid Helium-4 SPECIAL FEATURE
Visualization of two-fluid flows of superfluid helium-4 SPECIAL FEATURE Wei Guoa,b, Marco La Mantiac, Daniel P. Lathropd, and Steven W. Van Scivera,b,1 aMechanical Engineering Department, Florida State University, Tallahassee, FL 32303; bNational High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310; cDepartment of Low Temperature Physics, Faculty of Mathematics and Physics, Charles University, 180 00 Prague, Czech Republic; and dDepartments of Physics and Geology, Institute for Research in Electronics and Applied Physics, and Institute for Physics Science and Technology, University of Maryland, College Park, MD 20742 Edited by Katepalli R. Sreenivasan, New York University, New York, NY, and approved December 13, 2013 (received for review July 17, 2013) Cryogenic flow visualization techniques have been proved in not kept pace, in part due to the extremely low temperature and recent years to be a very powerful experimental method to study low density of the fluid. A number of early efforts were devoted superfluid turbulence. Micron-sized solid particles and metastable to producing macroscopic particles for qualitative investigations helium molecules are specifically being used to investigate in (10–12) and the challenge of producing neutrally buoyant par- detail the dynamics of quantum flows. These studies belong to ticles that faithfully follow the complex flow fields has been the a well-established, interdisciplinary line of inquiry that focuses on main impediment to quantitative advancement. In addition, sev- the deeper understanding of turbulence, one of the open problem eral attempts have been made to visualize fluid dynamics in su- of modern physics, relevant to many research fields, ranging from perfluid helium with microscopic tracers, which include neutron fluid mechanics to cosmology. -
The Noble Gases
The Noble Gases The Noble Gases (inert gases, Group 0, Group 18 or the helium group) are notoriously unreactive elements (‘noble’ means unreactive in chemistry) and in their elemental state they exist as monoatomic gases – gases whose ‘molecules’ are single atoms of the element, since the atoms are reluctant to react with anything, including one-another. This inertness is due to the fact that they have stable outer electron shells, with stable octets of electrons (full s and p subshells) except helium, which has a stable full inner shell. The electronic configurations are: Helium (He): 1s2 Neon (Ne): 1s2 2s2 2p6 Argon (Ar): [Ne] 3s2 3p6 Krypton (Kr): [Ar] 3d10 4s2 4p6 Xenon (Xe): [Kr] 4d10 5s2 5p6 Radon (Rn): [Xe] 5d10 6s2 6p6 Nevertheless, this group does have some interesting chemistry and also exhibit interesting physical properties. Reactivity increases down the group. Often helium is included as the first member of the group. Helium (He) Helium is chemically a highly unreactive element. It only forms transient species when electric discharges are passed through a mixture of helium gas and another gaseous element. for example, passing an electric discharge through a mixture of helium and hydrogen forms the transient molecule HHe, which has a very short half-life. HHeF is metastable. Neon (Ne) Neon is chemically the most unreactive element. It forms no true compounds, and no neutral molecules. Ionic molecules are known, e.g. (NeAr)+, (NeH)+, (HeNe)+ and Ne+. Argon (Ar) The unstable argon fluorohydride, HArF, is known. Ar also forms clathrates (see krypton) with water and highly unstable ArH+ and ArF are known. -
The Noble Gases
INTERCHAPTER K The Noble Gases When an electric discharge is passed through a noble gas, light is emitted as electronically excited noble-gas atoms decay to lower energy levels. The tubes contain helium, neon, argon, krypton, and xenon. University Science Books, ©2011. All rights reserved. www.uscibooks.com Title General Chemistry - 4th ed Author McQuarrie/Gallogy Artist George Kelvin Figure # fig. K2 (965) Date 09/02/09 Check if revision Approved K. THE NOBLE GASES K1 2 0 Nitrogen and He Air P Mg(ClO ) NaOH 4 4 2 noble gases 4.002602 1s2 O removal H O removal CO removal 10 0 2 2 2 Ne Figure K.1 A schematic illustration of the removal of O2(g), H2O(g), and CO2(g) from air. First the oxygen is removed by allowing the air to pass over phosphorus, P (s) + 5 O (g) → P O (s). 20.1797 4 2 4 10 2s22p6 The residual air is passed through anhydrous magnesium perchlorate to remove the water vapor, Mg(ClO ) (s) + 6 H O(g) → Mg(ClO ) ∙6 H O(s), and then through sodium hydroxide to remove 18 0 4 2 2 4 2 2 the carbon dioxide, NaOH(s) + CO2(g) → NaHCO3(s). The gas that remains is primarily nitrogen Ar with about 1% noble gases. 39.948 3s23p6 36 0 The Group 18 elements—helium, K-1. The Noble Gases Were Kr neon, argon, krypton, xenon, and Not Discovered until 1893 83.798 radon—are called the noble gases 2 6 4s 4p and are noteworthy for their rela- In 1893, the English physicist Lord Rayleigh noticed 54 0 tive lack of chemical reactivity. -
Design and Fabrication of the 1.9 K Magnet Test Fa- Cility at BNL, and Test of the First 4 M-Long MQXF Coil
Mon-Af-Po1.01-05 1 Design and Fabrication of the 1.9 K Magnet Test Fa- cility at BNL, and Test of the First 4 m-Long MQXF Coil J. Muratore, M. Anerella, P. Joshi, P. Kovach, A. Marone, P. Wanderer Abstract— The future high luminosity upgrade of the Large Had- vertical superconducting magnet test facility of the SMD at ron Collider (LHC) at CERN will include twenty 4.2 m-long BNL has been upgraded to perform testing in superfluid He at Nb3Sn high gradient quadrupole magnets which will be compo- 1.9 K and 1 bar, the operational condition at the LHC. This nents of the triplets for two LHC insertion regions. In order to test these and four pre-production models, the vertical supercon- has involved extensive modifications of the 40-year old, 4.5 K ducting magnet test facility of the Superconducting Magnet Divi- cryogenics plant and vertical test facility at the SMD. These sion (SMD) at Brookhaven National Laboratory (BNL) has been upgrades include new piping, compressors, and other critical upgraded to perform testing in superfluid He at 1.9 K and 1 bar, components; a new vertical test cryostat with a top plate and the operational condition at the LHC. This has involved extensive hanging fixture which can accept larger diameter and longer modification of the 4.5 K cryogenics plant, including piping, magnets, up to an actual length of 5 m; a 1.9 K heat exchang- compressors, and other upgraded components; a new vertical test cryostat which can accept larger diameter magnets; a modern- er; a newly designed warm bore tube; and a lambda plate de- ized power supply system upgraded with IGBT switches and fast signed with a novel sealing scheme to provide for both shutoff capability, and that can supply 24 kA to test high field strength and minimum heat loss. -
How to Fill with Liquid Helium
How to Fill with Liquid Helium These instructions are an introduction (or a reminder) of how to transfer liquid helium from a dewar to an instrument such as a magnet or a cryostat. In many cases you will want to pre-cool with liquid nitrogen, which is much more efficient that helium for cooling from room temperature to 80 K. Specific details about the instrument are available in the appropriate instruction manuals. 1. Make sure to always wear safety glasses and gloves whenever transferring liquid helium or liquid nitrogen. Also make sure that anyone you are working with or who is in the area is wearing safety glasses and is aware of what you are doing. 2. On the dewar, open the top valve and close the pressure relief valve. 3. Slowly put the transfer tube into the dewar. Make sure the pressure gauge is firmly seated and slide the tube all the way to the bottom. 4. On the instrument, open the helium fill port and the helium exhaust port. 5. If the cryostat is warm (does not have any helium in it), you can put the transfer tube into the helium fill port at once. If you are refilling an instrument, do not put the transfer line in until liquid is coming out (otherwise you will blow out what liquid is in the instrument with high pressure gas from the dewer). Liquid is coming from the tube when you see a thick white plume of gas. 6. To force liquid through the transfer tube, you need to maintain a pressure of 3-5 psi on the dewar. -
Cryostat Design
Published by CERN in the Proceedings of the CAS-CERN Accelerator School: Superconductivity for Accelerators, Erice, Italy, 24 April – 4 May 2013, edited by R. Bailey, CERN–2014–005 (CERN, Geneva, 2014) Cryostat Design V. Parma1 CERN, Geneva, Switzerland Abstract This paper aims to give non-expert engineers and scientists working in the domain of accelerators a general introduction to the main disciplines and technologies involved in the design and construction of accelerator cryostats. Far from being an exhaustive coverage of these topics, an attempt is made to provide simple design and calculation rules for a preliminary design of cryostats. Recurrent reference is made to the Large Hadron Collider magnet cryostats, as most of the material presented is taken from their design and construction at CERN. Keywords: superconductivity, cryogenics, vacuum, heat transfer, MLI, construction technologies. 1 Introduction The term cryostat (from the Greek word κρύο meaning cold, and stat meaning static or stable) is generally employed to describe any container housing devices or fluids kept at very low temperatures; the notion of ‘very low temperature’ generally refers to temperatures that are well below those encountered naturally on Earth, typically below 120 K. The very first cryostats were used in the pioneering years of cryogenics as containers for liquefied gases. The invention of the first performing cryostats is generally attributed to Sir James Dewar (Fig. 1), and hence cryostats containing cryogenic fluids are nowadays also called dewars. In 1897 Dewar used silver-plated double-walled glass containers to collect the first liquefied hydrogen. Even though the heat transfer phenomena were not well mastered during his époque, Dewar understood the benefits of thermal insulation by vacuum pumping the double-walled envelope, as well as shielding thermal radiation by silver-plating the glass walls.