Cold Facts Digital – The go-to place for Cryogenics and Superconductivity

How much heat energy does LN2 contain per lb.?

I would like to know how much heat energy liquid nitrogen contains per lb. In other words, per lb. of liquid, how many BTUs of heat would N2 absorb in the process of coming up to about 60F? I want to capture the cold energy of nitrogen as it vaporizes...

Software for thermophysical properties of helium down to 1K

What are the options when it comes to software for thermophysical properties of helium at temperatures down to 1K? I know Hepak – is it still the most commonly used package?

Refilling process of a helium cryogenic plant

I’m trying to collect some information about the refilling process of a helium cryogenic plant. Due to the physiologic losses I expect to have to foreseen a periodic refilling of helium. Our plant will be characterized by a refrigerator/liquefactor. A control cryostat with 4.5 K LHe coming from the liquefactor...

What's the best gas to use for pulse GMAW?

I have a 78″ ID vessel, 3/8″ thick shells, ½” heads, from SA-240-304L, which will have an ASME U-Stamp and I am planning on sub-arcing the seams and using pulse GMAW (ER308L for both) for the nozzles. I am comfortable with the SAW, but I am wondering about the best...

Manufacturer of liquid pump for use at 170 K

We’re in need of a liquid pump for use at 170 K in our refrigerator to pump Paratherm cryogenic heat transfer fluid. Can anyone suggest a manufacturer? Our flow rate is 16 liters/minute, and a head of 10 m. The specific gravity of the fluid is 0.85 and the viscosity...

Question about configuration of an 80 K helium circuit

I have a question about a possible configuration of an 80 K helium circuit from our cryogenic plant. A helium flow at 80 K and 18 bar is needed at the customer’s inlet. In order to decouple the refrigerator from the customer, I thought to propose the following solution: –...

Latest in Defining Cryogenics

Refrigerators and Liquefiers

Two of the most common terms used in cryogenics are “refrigerator” and “liquefier.” These terms describe similar and, as will be seen, in some cases identical components. A refrigerator provides cooling (that is, absorbs heat) at cryogenic temperatures. Refrigerators typically put a working fluid (such as helium) through one of...

Air Separation

Air separation is one of the largest, as well as earliest, industrial applications of cryogenics. In this process, cryogenic temperatures are used to separate air into its constituent gases: nitrogen (78.08%), oxygen (20.95%), argon (0.93%) and carbon dioxide (0.3%). Trace gases such as krypton, neon, xenon and helium total far...

Coefficient of Performance and Figure of Merit

The coefficient of performance (COP) is used to describe the effectiveness of refrigerators, including those operating at cryogenic temperatures. The COP is defined as the amount of heat removed at the cryogenic operating temperature of the refrigerator divided by the amount of work that must be applied to remove the...

Latest in Cryo Central

Air Separation and Liquefaction

by Nils Tellier, PE, President, EPSIM Corporation (CSA CSM) nils@epsim.us All illustrations courtesy EPSIM Corporation Background History of Air Separation and Liquefaction This section builds on a rich history of methods to develop deep refrigeration and cryogenic liquefaction during the 19th Century. You are encouraged to read Cryo Central’s History...

Bose-Einstein Condensate

A Bose-Einstein condensate, first proposed in 1925 by Albert Einstein based on work done by Satyendra Nath Bose (the same Bose from whom the term boson is derived), is a super-cold state of matter in which almost all of the individual atoms have “condensed” down to the lowest possible quantum...

Cold Technology for Pest Control

While it does not reach temperatures cold enough to be called cryogenic, carbon dioxide snow is at the heart of a new way of dealing with unwanted pests. It utilizes a quick freezing process that takes advantage of the properties of carbon dioxide snow and has a number of benefits...

Cryogenic Finishing

The following 3 articles discuss the uses and procedures of various type of cryogenic finishing. 1) By Robin A. Rhodes, Cryogenic Institute of New England, Inc. rrhodes@nitrofreeze.com Cryogenic Deflashing is employed to remove undesired residual mold flash that remains on molded parts after they are removed or ejected from the...

Latest in Ask the Experts

Seeking recommendations for commercial sensors

I would like to measure vibrations in small LHe cryostats. Could anybody recommend commercial sensors which would be suitable for the purpose? I am interested in the frequency range between 1Hz and a couple of KHz, with particular attention to the low frequency side.

Estimating cost of carbon steel, pure helium storage tanks

In order to perform an indicative cost assessment of our helium cryogenic plant (still in the design phase), I need an estimation of the cost of carbon steel room temperature pure helium storage tanks. The storage pressure is 20 bar. Can anyone give me suggestions about how to estimate the...

Supplier of pressure sensor that works down to 4.2 K

In an actual experiment we would like to measure the static pressure in a cryostat in the range between one and four bar. Therefore we are looking for some (more or less) cheap pressure sensors that work in liquid helium in the pressure range up to five bar. Unfortunately all...

Looking for reference/textbook suggestions

Can you suggest some reference textbooks for practical thermodynamics applications in cryogenic fields? I need textbooks with cryogenics calculations and examples, dimensioning procedures, second principle applications in cryogenics, heat load calculations, cryogenic pump application, etc. Do such books exist? Does any similar source of information exist?

CATEGORIES