Although liquid nitrogen tank is a general term, whether it is open top or self-pressurized can be called liquid nitrogen tank, liquid nitrogen storage tank.
However, the traditional meaning of liquid nitrogen tank refers to the open top liquid nitrogen tank.
That is, liquid nitrogen storage containers labeled with a caliber and used for long-term storage of biological samples.
This type of liquid nitrogen tank is also called “non-pressure liquid nitrogen tank”!
Because of the consideration of safety, the safety of the user, but also the safety of the use of the jar!
Liquid nitrogen is a liquid with a very low boiling point, at around -196°C.
The lower boiling point means that it is not “stable” at room temperature and will volatilize at the slightest contact with room temperature.
Liquids are turned into gases with pressure.
If the pressure is in a container and cannot be released, it will accumulate and then expand beyond what the container can withstand is dangerous!
Therefore, to ensure safety, the liquid nitrogen storage tank has a neck plug but the neck plug is loose, leaving the gas outlet to release the pressure.
As a result, there is no pressure in the liquid nitrogen storage tank.
Moreover, these types of liquid nitrogen tanks are used for biological sample storage and do not use pressure at all. The presence of pressure does no good except to add to the potential problems.
Even for self-pressurized liquid nitrogen tanks, the storage state is no pressure, and a special venting valve is added to release the pressure!