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Information on valve specs

  1. Feb 1, 2007 #1
    I am wondering if anyone has a source for the specs on beverage container valves? I am looking for replacement o-rings and I don't have the valves in front of me, so if someone has a source for the specs, that would be great. Thanks!
  2. jcsd
  3. Feb 1, 2007 #2


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    Hi rocks. What do you mean by "beverage container valves"?

    I'd normally recommend the http://www.parker.com/o-ring/Literature/ORD5700.pdf"for O-ring information, but if you just want to figure out the size of an O-ring, a reference such as this one might be a whole lot easier to use:
    http://www.rtdygert.com/pdf/OringSizeGuid.pdf [Broken]

    O-rings come in standard sizes per AS568. The size is designated with a three digit dash number such as -120 for example. The first digit, the 1, tells you the O-ring cross sectional diameter or thickness. The second and third numbers specify the ID of the ring. Just measure up an existing O-ring or even just the gland it goes into, and use the above chart to determine the size.

    There's also a series of O-rings not covered by this spec. They're commonly used to seal threaded fittings, also known as SAE threaded boss or fitting, and sometimes specified to a military standard such as MS16142. So if your O-rings are used to seal a fitting that screws into a straight threaded SAE boss, there's a different series of O-rings to use.
    Last edited by a moderator: May 2, 2017
  4. Feb 1, 2007 #3
    Thanks -- I do have the Parker Handbook. The problem is I don't know what this valve is going to measure because it is being shipped from overseas so it will be a bit before it gets here.

    Apparently, this valve uses some interface standard called a beverage interface or something similar. I am assuming it would be for CO2 systems for pop or beer -- and is supposed to be stronger than standard interfaces with cylinders under high pressure. I want to know about this standard and its dimensioning so that I can order O-rings for it!

  5. Feb 2, 2007 #4


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    hi rocks. If you're in the US, the Compressed Gas Association (CGA) governs the various styles of connections (fittings) that go on packaged gasses. There's a few hundred different gasses, including CO2 that have standard interface dimensions given by specification CGA V-1. Each standard interface is different, the intent is to prevent someone from accidentally connecting the wrong type of gas or liquid to a system. For example, hospital oxygen systems may have someone delivering oxygen cylinders, and that same company may also have nitrogen deliveries. By having different fittings, even though the company may deliver the wrong product, the connections won't fit, so you can't hook them up. Needless to say, piping nitrogen into a hospital oxygen supply would kill a lot of people and unfortunately that's happened. Different fittings minimize the risk, but nothing's idiot proof.

    Note that all the interface dimensions on V-1 are for compressed gas cylinder valves, but they also include some liquids such as liquid CO2. I'm sure if you're in the US, the cylinder valve on any CO2 container will be per this specification.

    I had to look up the CGA connections for CO2, and I see they have about a half dozen, so I'd be guessing which connection you're going to receive. Nevertheless, I'll take a guess. There's a CGA 323 which is for cylinder valve outlets, and is good to 1800 psig. They give dimensions of .070 x .551 ID. That gives me a -015. I'll attach the relevant pages.

    There's a large number of CGA standards, the one I quoted you covers valve connections, but there are also larger transfer connections for CO2 in a second spec. I see they also use O-rings but the nominal pipe size on these other connections start at 2" and go up to 4". I don't suppose you're using something that large are you? If so, they don't list O-ring size, but I could give you something that would fit.

    One thing to note here, is that these specs only cover dimensions, not materials. It is up to the owner to determine material. For both dry and wet CO2, your best bet is nitrile.

    Attached Files:

  6. Feb 5, 2007 #5
    Thanks for the info -- I will take a look at it an see if it fits with what I've got coming!
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