Does anyone know of a method with which to reliably move components in a cryogenic environment? We are interested in moving detectors in a cryogenically cooled (2K) vacuum chamber, which is contained within a larger cryostat/isolation vacuum with thermal shields. As the desired horizontal or vertical displacement is between 10 cm to 40 cm depending … Continue reading Method to move components in a cryogenic environment

Where can I obtain a really big, nice TS diagram for helium ?

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?

I am currently working on the design of a focal plane assembly to be implemented on a small satellite (4 EMCCD detectors) to be operated at -80°C (which is not really cryogenic and likely still considered boiling hot for most of you :-). As it is passively cooled, the assembly will experience about -120°C during … Continue reading Reliability and mounting of electronic substrates at low temperatures

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 will be used to recirculate … Continue reading Refilling process of a helium cryogenic plant

I have a question concerning the 3D drawings of a cryogenic plant. The integration of the 3D drawings of a plant with the 3D main model of a new laboratory or a new facility can be a complex work that takes a lot of time. I would like to know if the principal companies that … Continue reading Are 3D drawings included in the sale of a cryogenic plant?

I have been looking for a source of LOX impact testing to ASTM D2512. I am aware of NASA and White Sands, but am looking for a commercial entity doing the work. No luck so far, even calling a lot of the folks on the CSA website. Any referrals will be greatly appreciated!

I would like to know how to calculate the equivalent refrigeration capacity at 4.5 K of a cryogenic system operating at higher temperature.

I have to maintain a certain mass (some tons) at 100 K by circulating in it GHe (through apposite channels). How can I calculate the flow rate needed? I suppose that the delta T (T inlet and T outlet) and the heat load on the mass are necessary. Knowing the temperatures I can find the … Continue reading Need help with calculating flow rate

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

What do cryogenics companies do about liability insurance? Is there a special type for cryogenics?

Are you aware of permitting or license requirements (other than local city or town) needed for the storage or transportation of cryogenic materials?

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.

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 US collecting correlative samples for … Continue reading Pros and cons of barcoding samples

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 is 38 cSt.

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: - The gas helium stream at … Continue reading Question about configuration of an 80 K helium circuit

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?

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.

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.

Currently we use in our Biobank an upright -80 freezer to store all our samples. We are planning to buy a fully automated bio-repository storage that will do the picking of samples under restricted conditions. But in the meantime I foresee that we have to pick the samples manually. The disadvantage of upright freezers is … Continue reading Need help comparing chest freezers and upright freezers