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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.

Pier Oddone to step down as Fermilab director

Fermilab Director Pier Oddone has decided to retire after eight years at the helm of America’s leading particle physics laboratory. Oddone will continue to serve as Fermilab director until July 1, 2013, while a committee appointed by the FRA Board Chairman conducts an international search for his successor.

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Regenerators

Regenerators or regenerative heat exchangers are a key component of cryocoolers such as pulse tube cryocoolers (Cold Facts, August 2014). Regenerator performance greatly affects the coefficient of performance of cryocoolers. Improvements in regenerator design and, in particular, regenerator materials have been an important factor in the improvement of the performance...

Pulse Tube Cryocoolers

The development of pulse tube cryocoolers has been a significant topic of research and development over the past 20 or so years. Pulse tube cryocoolers have a number of advantages over other types of cryocoolers and are now available commercially. In order to understand pulse tube cryocoolers, it’s best to...

Thermal Expansion

Thermal expansion refers to the change in size (length or volume) that a material undergoes as its temperature changes. In cryogenic systems this effect can be quite large and must be allowed for in the design. In isotropic materials, which include most engineering materials, the thermal expansion is the same...

Wind Tunnels

Dr. Robert Kilgore The development of the cryogenic wind tunnel is one of many significant breakthroughs in both cryogenics and wind-tunnel technology made during the past millennium. Interest in the development of high-speed commercial and military aircraft resulted in a review of problems of flow simulation in transonic wind tunnels...

History of Cryogenics

From the Fall 1999 issue of Cold Facts magazine Millennium Breakthroughs A variety of CSA members give different perspectives on the past millennium: What were the most significant breakthroughs in cryogenics during the past millennium? Prof. R.G. Scurlock, Kryos Technology, scurlock@soton.ac.uk (“Breakthrough” = way through obstacles — Oxford English Dictionary)...

Cryobiology

Andreas Sputtek Past President Society for Cryobiology sputtek@uke.uni-hamburg.de or http://www.sputtek.de/. The word cryobiology (from the Greek words “cryo” = cold, “bios” = life, and “logos” = science) literally signifies the science of life at low temperatures. In practice, this field comprises the study of any biological material or system (e.g.,...

Cryogenic Insulation

James E. Fesmire Cryogenics Test Laboratory NASA Kennedy Space Center james.e.fesmire@nasa.gov Introduction In today’s world, the use of cryogenics and low-temperature refrigeration is taking a more and more significant role. From the food industry, transportation, energy, and medical applications to the Space Shuttle, cryogenic liquids must be stored, handled, and...

An Issue of Pressure and Flow Rate in a Supply Tank

Please help solve this problem: A supply tank requires a vaporizer to generate sufficient pressure to pump stored fluid up into a vehicle or tank. The available head is limited as the tank level falls and it is important to minimize the system pressure drop to maintain the desired flow...

Using MLI on VJ Line Joints or Cryo Storage Tanks

When installing Multi Layer Insulation (MLI) blankets on VJ line joints or cryo storage tanks should they be wrapped and tied down tight or loose? These are usually pre-cut to size. Also should they have an access hole at the point of where the molecular sieve is installed to help...