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

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: –...

Properties for steel 1.4037 at 77 K

Does anyone know the properties at 77 K for steel 1.4037 ( X 65 Cr 13) which is used for ball bearings? We are looking for values of thermal expansion.

Curiosity sends high-resolution color images from Gale Crater

NASA's Curiosity rover has shipped back to Earth high-resolution color images of its surroundings on Mars, sharpening our views of an intriguing channel, layered buttes and a layer of cobbles and pebbles embedded in a finer matrix of material.

Latest in Defining Cryogenics

Helium-3

Helium-3 (3He) is one of the two stable isotopes of helium. The other is the much more common Helium-4 (4He). Neither of these isotopes should be confused with He II, which is the second liquid phase of 4He. He II was discussed in this column in the Spring 2010 edition...

Cryopumping

Cryopumping refers to the use of cryogenic temperatures to produce vacuum in enclosed spaces. More broadly, it can also refer to the removal of gases via cryogenic temperatures from a flow stream or enclosure without necessarily resulting in vacuum pressures. This is an important application of cryogenics and is used...

Thermal Acoustic Oscillations

Thermal Acoustic Oscillations (TAO) are a common event in cryogenic systems that can have significant adverse effects on the performance of the system. TAOs are sustained pressure oscillations that can occur in tubes containing gas, closed at one end (the warm end) that have a very large temperature gradient along...

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

Presence of alloying elements in tool steels

I want to expand my knowledge of cryogenics in general and tool steels in particular. Specifically, I am keenly interested in learning about the presence of alloying elements in tool steels and how their presence in various combinations affects the performance of tool steels after cryogenic treatment.

Pros and cons of barcoding samples

I was wondering if I could ask for input on pros and cons of barcoding. We are in the process of trying to decide if we should start barcoding our samples and I’m just not sure if this is feasible for our organization. We have numerous sites all over the...

Purity level of helium gas stream in cryo plant purification system

I would like to know what the principal methods and the relative instrumentation to check the purity level of helium gas stream in the purification system of a common helium cryogenic plant are. What principles are these instruments based on? And what are their principal characteristics?

LN2 for cryopreservation through controlled rate freezing of samples

I am the cryogenic specialist for a stem cell bank in Greece. I am trying to find the minimum requirements (purity, humidity, etc.) of liquid nitrogen for cryopreservation through controlled rate freezing of biological samples.

CATEGORIES