Liquid helium transport/laboratory storage Dewars
The CF-100 helium Dewar is designed for minimum loss storage, transportation, and dispensing of liquid helium. The CF-100 container employs state-of-the-art vapor cooled multishield technology in conjunction with superinsulation to effect the lowest guaranteed loss rates in the industry on comparable units. The advanced insulation system results in quicker, more efficient cool down without the need for nitrogen pre-cooling. In addition, the elimination of LN2 or helium gas circulation shielding means that the CF-100 is virtually maintenance-free.
These units have the same general areas of use as old-style, 4-wall helium containers but permit large storage capacities in small packages with lighter weight.
Model | Gross capacity | Daily boil-off rates | Overall height* | Body diameter | Empty weight | Transfer line fittings |
CF-100 | 110 L | 1% | 1.5 m (59 in) | 0.6 m (24 in) | 95 kg (210 lb) | 3/8 in or 1/2 in |
*NOTE: Overall height includes 4 in casters. |
Pulsation dipstick
This simple liquid helium probe provides an accurate indication of the liquid level in a storage Dewar or research cryostat. The configuration on the right has a thin rubber diaphragm o-ring sealed over the upper portion of the dipstick. The assembly is connected to a small diameter stainless steel tube that is inserted into the liquid helium. The overall length of the stainless steel tube is designed to the customer's specification. The dipstick produces a steady low-frequency pulsation when immersed in liquid helium, which can easily be felt at the diaphragm with a fingertip. When the dipstick is raised just above the liquid level, a high-frequency pulsation occurs. The stainless steel tubing is attached to the diaphragm assembly by a threaded fitting and is easily replaceable.