• 200 Litre capacity Helium Liquefier Dewar with built-in transfer line and level probe

• Fully Automated Touch Panel Control (10.6”)

• Stand-alone display of liquid helium level and (4) internal temperature sensors

• 1.5 Watt @4.2K Sumitomo Refrigerator

• Air or Water Cooled compressor

• Internet and Wireless enabled

• Direct Helium Gas Recovery system included

• (optional: high pressure recovery to gas cylinders)


PAHL Small:

• Sumitomo 1.5 Watt refrigerator

• Compact 18 Litre Dewar with built-in transfer line and level probe

• Stand-alone display of liquid helium level and (4) internal temperature sensors

• Direct Helium Gas Recovery system included

• Built -in liquid nitrogen pre-cool

• Ideal for use in smaller laboratories

• (optional: all-in-one integrated gas storage)

PAHL Liquefier Features/Benefits:

1. Higher or Equal Liquefaction Rate at Lower Pressures

Liquefaction at lower pressures allows for safer and more efficient system operation as well as greater versatility in matching liquefier to experimental dewar pressure. Typical liquefaction is 24 l/day at 5.5 PSI [PAHL 200].

2. Separate Ports for Gas Input/Output

A separate gas port allows for very fine pressure adjustment without directly warming the refrigerator.  The result is a more efficient liquid helium transfer.

3. Exclusive Integral (Built-In) Transfer Line

CRYO’s integral transfer line allows for simpler liquid helium transfers. Losses and complexities of inserting and removing the transfer line are eliminated.  To quote a User:

“Transferring liquid helium from the PAHL200 is easier than transferring from a storage dewar”.

4. Shut-Off Loss Rate of Liquefier (Dewar) is Lower

Should the power be shut-off to the liquefier (i.e. in case of a power outage) and the refrigerator is turned off , the loss rate of the CRYO custom built dewar is extremely low (especially in the first 24 hours of refrigerator shut-down).

Loss rate of the Liquefier (Dewar) averaged over 24 hours is 0.075 l/hr

Loss rate of the Liquefier (Dewar) averaged over 72 hours is 0.280 l/hr


5. Very Efficient Duty Cycle

When in standby mode the system can be turned off for twelve hour periods with no loss of liquid helium.

6. Dewar Vacuum

The CRYO liquefier dewar requires no maintenance and no vacuum pumping for ten years or more!

7. Touch Panel Display and Stand-Alone Monitors

The system includes a touch-screen, removable Windows based tablet which displays system parameters. Additional separate stand-alone Liquid Helium level and temperature sensor monitors are included.

8. Reliable, Long-Term Operation

• Zero-Maintenance dewar

• Built-in gas purification system

• Highly dependable refrigerator

Complete Liquid Helium Generator System Features:


• Liquid helium production rate of:

  - PAHL200: up to 24 litres/day*

  - PAHLsmall: 18 litres/day*

• Two stage Sumitomo SHI model SRDK-415D GM (1.5W@4K) closed cycle refrigerator coldhead (Gifford-McMahon)

• Water or Air Cooled Compressor(s) available

• Temperature sensors installed on refrigerator first and second stage(s), bottom of LHe reservoir and dewar neck.

Custom Built Liquid Helium Storage Dewar:

• Storage dewar custom built to match refrigerator and actively cool the dewar shields

• Approximate Helium Reservoir:

  - PAHL200: 200 litres

  - PAHLsmall: 18 litres

• Demountable valve evacuation port

• High efficiency transfer using separate pressurization port

• Safety pressure reliefs, Electrical feedthroughs, Gas Vent valve, compound pressure gauge

CRYO Exclusive Two Piece Liquid Helium Bayonet Transfer Line

• Design allows bayonet transfer line to remain in dewar - ready for immediate use

• Mating Liquid Helium bayonet vacuum insulated transfer line with 60” stainless steel flex length (can be customized)

• Allows operation in low ceiling height, as bayonet is inserted horizontally

Liquid Helium Level Monitor and Probe

• Installed superconducting LHe level probe

• Digital readout monitor

• Sample-and-hold feature

• RS-232 computer interface

• Fully Automated Touch Panel Control (PAHL200 only)

Temperature Monitor

• Four multipurpose input channels

• LED display

• Remote interfaces include Ethernet, RS-232

Direct Recovery System

• Gas Flow controller

• Research Dewar/Cryostat Pressure Regulator

• Gas manifold assembly


• System fully assembled and tested


*Liquefaction rate will vary dependent upon gas pressure and purity