Cylinders regulation

Air from a cylinder at pressures up to about 10 bar (150 psi) is applied to a gas piston that has a relatively large surface area. The gas piston is attached to a hydraulic piston that has a smaller surface area. The pressure applied to the liquid = gas pressure x area of gas piston/area of hydraulic piston. With 10 bar inlet pressure and a 50 1 area ratio, the hydraulic pressure obtained is 500 bar (7500 psi). On the drive stroke, the outlet valve on the pump head is open to the column and the inlet valve closed to the mobile phase reservoir. At the end of the drive stroke, the air in the chamber is vented and air enters on the other side of the gas piston to start the return stroke. On the return stroke the outlet valve closes, the inlet valve opens and the pump head refills with mobile phase. The pump can be started and stopped by operation of a valve fitted between the cylinder regulator and the pump. 

Steere, N. V. Ed., 1971, Handbook of Laboratory Safety, The Chemical Rubber Co. Press, Cleveland. Contains a chapter on compressed gas cylinders and cylinder regulators. 

Figure 7.2 Gas cylinder regulator plus 3-way needle valve outlet Remove the protective cap from the cylinder fitting and ensure that the fitting is clean and dry.

Pressure regulators are used to reduce gas pressure to accommodate a system s parameters. They are used for cylinder service or in-line service. Cylinder service requires a cylinder regulator with a particular CGA inlet to handle high pressure, and which is specific to the gas used. The outlets on the cylinder regulator will vary depending on their purpose. 

The inlet and outlet pressure rating of the regulator should be compatible with your needs. If you need a specific or a certain range of delivery pressures, purchase a regulator that meets your specifications. Cylinder regulator inlets operate within common cylinder delivery pressures. For both hydrogen and nitrogen, these pressures are around 2200 psi. 

Regulators are used to reduce cylinder supply pressure to a lower use pressure. As stated previously, hydrogen uses a CGA 350 cylinder valve. This requires a CGA 350 outlet connection on the regulator. Be sure that the regulator you purchase for cylinder use has a CGA 350 outlet connection. In line hydrogen regulators can have any variety of connections, but cylinder regulators must have the CGA 350 inlet connector. 

Most regulators are equipped with a relief valve, one or two outlet ports and I an inlet port. The inlet port of a hydrogen cylinder regulator has to have a CGA 350 valve connector which consists of a bullet shaped nipple and a nut. The. outlet fitting on the regulator can vary and can be changed and/or adaptors... 

The cylinder regulator is connected to the hydride bottle by a flexible stainless steel hose with a Vs" male NPT on one end and a Vs" NPT male fit-... 

To charge the hydride bottle, connect the hydride bottle to the cylinder regulator via the DESO stem connection. 

Cylinder regulator/ 400 psi delivery Fuel Cell Store 561213 1... 

A slow decrease in the flow rate into the DSC will be observed if cylinders are used that are fitted with single-stage regulators, as the output pressure will decrease as the cylinder slowly empties. This effect may be minimized by the use of two-stage cylinder regulators or, ideally, the use of calibrated mass flow controllers, which will remove this variable from the experiment altogether. 

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