The liquid nitrogen canister is a modified biological container based on the Dewar vacuum jacket principle.
It can store liquid nitrogen in a vacuum adiabatic structure to minimize the evaporation of liquid nitrogen.
We also store samples while preserving liquid nitrogen, using low-temperature -196°C liquid nitrogen to retain sample activity.
It is common sense that to reduce the evaporation of a certain liquid, the tank in which the liquid is stored can be made hermetically sealed.
But liquid nitrogen is not only a deep low temperature liquid of -196℃, but also a kind of liquid with low boiling point and easy to volatilize, with pressure after vaporization.
Therefore, if the liquid nitrogen canister is made completely sealed, the gas generated by the natural volatilization of liquid nitrogen will accumulate inside the tank, resulting in an increase in pressure inside the tank, there is no outlet to vent the gas, to the extent that the liquid nitrogen tank can not withstand, it is easy to explode!
Therefore, commercially available liquid nitrogen canisters leave a slit at the neck opening to facilitate the natural evaporation of liquid nitrogen to run out.
At the same time, also make the fittings neck plug more loose style, false plug neck mouth, both to reduce the volatilization of liquid nitrogen, but also to prevent the liquid nitrogen vaporization pressure rise, causing the container explosion.