What Are The Proper Procedures For Using A Dewar flask

A Dewar flask is a stainless steel pressure vessel insulated under vacuum. Its main function is to store and transport liquid oxygen, liquid nitrogen, liquid argon, carbon dioxide, or liquefied natural gas. It is a reliable and economical cryogenic liquid and gas transport device. Of course, this means that its operation and use must be standardized; otherwise, accidental injury and danger may occur. Therefore, what should we pay attention to in daily life?

1. When the Dewar flask (canister) is not in use, remember not to open the pressure valve. Check that the pressure valve is closed; otherwise, gas inside the canister will leak.

2. After stopping use, remember to close any open pressure valves. When using, only open the pressure valve.

3. When in use, if the pressure drop on the Dewar flask (canister) pressure gauge no longer increases when the pressure valve is fully open, it means there is no liquid phase inside the canister, only a gas phase.

4. During use, check all connections (dynamic and static seals) for leaks. Frosting during use is normal and can be easily confused with a leak in the Dewar flask (canister).

5. When the pressure booster valve is open, the system pressure must not exceed the design pressure. If the system pressure is too high, closing the pressure booster valve will not control the pressure. Quickly open the air valve to release pressure from the system, identify the cause, and then put the system back into use.

6. Check the pressure of the Dewar flask (tank) every half hour if possible. When the pressure in the Dewar flask (tank) is low, appropriately open or open the large system pressure booster valve to pressurize the system and prevent the liquid level from dropping too low.