Liquid Nitrogen Biological Container of Aluminum Alloy

Liquid nitrogen biological container can generally be classified into liquid nitrogen biological container for storage and liquid nitrogen biological container for transportation. The former can be further categorized into the standard one and the large-diameter one, which mainly find application static indoor storage of liquid nitrogen rather than long-distance transportation. The latter can be further categorized into standard one and one for air transportation. To be fit in with transportation conditions, shockproof design is necessary. Apart from static storage, it can be used in transportation when full of liquid nitrogen but also be free from intense collision and vibration.

1. Examination before use

Before filling in liquid nitrogen, the first thing to do is see if the tank shell has any depression and vacuum exhaust port has any damage. If the vacuum exhaust is damaged, vacuum degree will be reduced. Worse still, if there is air in it, the tank cannot keep warm so that frost will form on the tank shell, and more liquid nitrogen will evaporate, thus losing its use value. Next, inner tank should be examined to see if there is any foreign matter which must be taken out to guard against the erosion of liner.

2. Filling of liquid nitrogen

Filling of liquid nitrogen must be careful. For new tank or dry tank, cooling it before slowly filling in liquid nitrogen is necessary in that fast cooling will harm the liner and reduce service life. Vacuum exhaust port must be free of any liquid nitrogen; otherwise vacuum degree will be lower. Capping plug is made of insulation materials that prevent evaporation of liquid nitrogen and fasten the pail. Hence, when opening or closing the tank, one must reduce the friction so that service life can be extended.

 3. Transportation of liquid nitrogen in the tank:

When transporting liquid nitrogen medium, one should make sure that every valve of the tank remains the same when liquid nitrogen is in storage and the base of packing container is put under the circle of container holder. A rope is used to fasten the liquid nitrogen container tightly to a vehicle so that it will not move when being transported.

 4. Infusion of liquid nitrogen in the tank:

Follow the next procedures when liquid nitrogen has to be exported from the tank:

5. Examination of the tank in use

A tank has to be examined regularly when it is in use. The tank shell must be examined with eyes or hands to see if there is any frost; if there is, it is necessary to stop using it. Particularly, frost or ice on walls of the neck tube is not suitable to be removed by a knife; otherwise walls will be damaged so that vacuum is not pure. The right method is to take out the liquid nitrogen, and let frost or ice melt naturally.

Close the vent valve; open the booster valve; observe the pressure gauge; when the pressure reaches 0.05MPa (0.5kg/cm²), open the outlet valve for continuous infusion.