filling process of dewar cylinder

Before filling the Dewar cylinder with cryogenic liquid, first determine the filling medium and filling quality of the gas cylinder. To ensure accurate filling, please use a scale to measure.

1. Use a special delivery hose to connect the gas cylinder inlet and outlet valve (DPW cylinder is the inlet valve) to the supply source, and tighten without leakage.

2. Open the discharge valve and inlet and outlet valve of the Dewar, and then open the supply valve to start filling the pressure vessel.

3. During the filling of the pressure vessel, monitor the pressure in the bottle with a pressure gauge and adjust the discharge valve to maintain the pressure at 0.07~0.1MPa (10~15 psi).

4. When the Dewar has reached the required filling quality, close the inlet and outlet valve, discharge valve and supply valve.

5. Remove the delivery hose and remove the gas cylinder from the scale.
　　
Warning: Overfilling of gas cylinders is strictly prohibited.
Warning: Confirm the medium and filling medium in the Dewar before filling.
Warning: It should be filled in a well-ventilated place, because the accumulation of gas is very dangerous. Note: The pressure of a fully filled gas cylinder rises very quickly, which may cause the safety valve to open.
　　
Caution: After working on liquid oxygen or liquefied natural gas, since liquid oxygen or liquefied natural gas is likely to be splashed in clothes, please be careful not to smoke or near a fire.

Note: When the saturation pressure of liquid carbon dioxide drops to 0.48MPa (70 psi), liquid carbon dioxide will form solid dry ice. Therefore, when using DPL450-175H/195H/210H, DPL450-175V/195V/210V, DPW650-499H cylinders to fill liquid carbon dioxide, the carbon dioxide gas in the cylinder must be pressurized before filling.