Liquid Nitrogen Transport Dewar

What is the Liquid Nitrogen Transport Dewar?

A liquid nitrogen transport dewar is a rugged, low-volume vessel built to carry liquid nitrogen between locations, with a protective casing, handles and a vented lid. It is the right choice for moving liquid to remote instruments or smaller storage dewars where a fixed supply is unavailable.

Overview

Transport dewars are made with a stainless steel inner vessel and a robust outer jacket that resists impact, since they are lifted, loaded into vehicles and carried across sites. Capacities of 2 to 35 L are common, with carrying handles, a vented cap that prevents pressure build-up and sometimes a wheeled cart or protective guard ring. The vented lid allows boil-off gas to escape but keeps splashing low, and static evaporation is moderate, typically 0.3–1.0 L per day depending on size. Unlike self-pressurizing dispensing dewars, transport units are generally poured or siphoned through a transfer tube. Users should check road and air transport rules for liquid nitrogen, since cryogenic liquids are regulated goods and vehicle ventilation is essential. These dewars are also used for carrying liquid nitrogen to bench instruments, cold traps and cryo-demonstration setups.

How does it work?

A liquid nitrogen tank consists of an inner vessel, usually aluminum alloy or stainless steel, suspended inside an outer shell by low-conductivity neck tubes and supports. The annular space is evacuated to a high vacuum and filled with multilayer aluminized film and adsorbent, which suppresses convection, conduction and radiative heat transfer. The remaining heat leak, mostly through the neck, boils nitrogen off slowly as a vapor that exits through the vent. Because no power is needed, the vessel works as a passive store, and holding time depends on volume, neck diameter and insulation quality. Samples sit in canisters, racks or goblets, either submerged in liquid or held in the cold vapor above it. Pressurized dispensing tanks add a relief valve and a pressure-building coil that drives liquid out through a withdrawal valve.

What are the key features?

• Stainless steel inner vessel with impact-resistant outer jacket for field handling.
• Vented cap prevents pressure build-up while limiting splashing during transport.
• Carrying handles and optional guard ring protect the neck and lid.
• Wheeled cart option supports larger sizes in corridors and lifts.
• Compatible with transfer tubes and funnels for safe pouring.
• Compact sizes fit benchtop instruments and cold trap refilling.

What are the technical specifications?

A typical liquid nitrogen transport dewar configuration offers capacity (liquid) of 2–35 L, static evaporation rate of 0.3–1.0 L/day, holding time (no refill) of 10–60 days, neck diameter of 30–50 mm, inner vessel material of Stainless steel and working pressure of Atmospheric (vented). Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Liquid Nitrogen Transport Dewar is used in liquid nitrogen delivery to labs, cold trap and instrument refilling, mobile veterinary work and cryo-demonstration and teaching. Across the wider Liquid Nitrogen Tanks class, laboratories also deploy it for fertility clinic gamete and embryo storage, biobank sample storage and cell line and hybridoma banking.

Which standards and certifications apply?

Relevant standards and methods include ISO 21009-1, ISO 21010, GB/T 18442, EU Pressure Equipment Directive 2014/68/EU, ISO 20387 and IATA Packing Instruction 202. Certification candidates for this model are CE, ISO 9001 manufacturing and UN packaging conformity for cryogenic liquids; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Install tanks in a ventilated room with an oxygen sensor, away from drains and enclosed spaces, and on a level floor rated for the filled weight. Never seal a storage tank airtight, because boil-off gas must be able to escape. Inspect the vessel regularly for frost on the outer shell or a rising evaporation rate, which suggests vacuum loss. Measure liquid level with a dipstick or sensor on a fixed schedule and record it. Clean with mild detergent and dry completely before refilling, and keep canisters and lids free of ice. Users should wear cryogenic gloves, a face shield and closed footwear. Recertify transportable vessels according to local pressure-equipment rules.

How do I select the right Liquid Nitrogen Transport Dewar?

Select a transport dewar for carrying liquid nitrogen to other locations. Choose a dispensing dewar if you need pressurized withdrawal, and a dry shipper if you ship samples. In an RFQ, specify capacity, cap type, need for a cart or guard ring, expected transport method and any local transport regulation certificate requirements.

How does it compare with other Liquid Nitrogen Tanks variants?

The first decision is function: storage, transport or dispensing. For storage, choose the neck diameter and capacity to suit the vial format, since wide-mouth tanks hold more vials and allow easier access but lose liquid faster. Compare static evaporation rate and holding time at the stated fill level, and ask for the test method. For transport, prioritize vibration and tilt resistance, a lockable lid and a rated holding time during shipping, and confirm airline and IATA rules for dry shippers. For dispensing, check working pressure, withdrawal valve type and whether a pressure relief device is fitted. Consider construction material: aluminum is light, stainless steel is stronger. Also specify a level indicator or gauge, casters, and a lockable lid for material that requires audit control.