Storage/ Fill Dewars

Kadel Engineering manufactures liquid helium and liquid nitrogen laboratory use storage dewars in capacities from 5 to 240 liters.  As with all our products, any existing designs can be customized to meet a particular customers needs.


Typical Construction

  • Aluminum or stainless steel reservoir and outer vacuum shell
  • Multi-layer superinsulation
  • Charcoal gettering for long vacuum life
  • Re-pumpable vacuum valve
  • Self-pressurizing or pour fill


  • Pressure building coil
  • Gas use valve
  • Liquid withdrawal devices and hoses
  • Pressure gauge
  • Wheel castors
  • Lifting lugs

Gravity Feed Dewars

Gravity feed dewars are commonly used to maintain liquid levels in cold traps, dewars, and other devices to extend the hold time. Gravity feeders are reliable with no moving or electrical parts and are virtually noise free when used with detectors.  They can be an effective choice when then use of an automatic fill system is impractical.

The gravity feeder is positioned on top of the device to be supplied with liquid.  A gas seal (via o-ring) is made between the two devices.  This seal can be made utilizing the weight of the gravity feeder, or by screws in the mating flange for maximum safety of operation.  Cryogen is dripped thru a vacuum insulated feed tube exiting the bottom of the gravity feeder.  As the liquid level in the lower tank drops, it is replenished from the gravity feeder.  All vent gases exit thru the feed dewar neck tube.  The feed dewar operates at atmospheric pressure with a loose fitting plastic neck plug.