Hydrogen valve outlet connections

The standard valve outlet connection in the United States and Canada for hydrogen bromide cylinders is Connection CGA 330. [8]... 

Hydrogen regulators, cylinder valves and outlet connections... 

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. 

HB X V4 MPT barb. This particular combination is what was available at the local hardware store, but you may find a more suitable one piece connector reducer. This connects the /8 ID tubing from the top of the 3 way valve to the V2" ID tubing that goes to the hydrogen gas outlet on the electrolyzer. 

The two main valves used in this system, located on the hydrogen and oxygen outlets, have Yor-Lok tube connections. More valves could be added to the system, depending on your system parameters. 

As hydrogenation vessel a strong-walled, tested pressure flask is used, which is closed by purified rubber stoppers made safe for pressure work in the usual way. Thick-walled pressure tubing, in perfect condition, is used for connection to the outlet valve 3. The tubing and stoppers should have been boiled several times with 20% sodium hydroxide solution, until the liquid is no longer colored yellow, and then washed carefully and repeatedly with hot distilled water. 

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