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How do one reduce the pressure?

  1. Jan 29, 2008 #1
    Hi all.
    I have a air pressure supply of 4 bar and I need to reduce it to say a few thousands Pa.
    What I have now is a pressure regulator that can reduce the pressure to 0.1 bar, but I need a even smaller pressure.
    Is there any device that I can use?
    I heard something called throttle valve? is it something I can use?
    It reduces pressure by percentage or to a certain level?
    Please kindly help. Thanks.
     
  2. jcsd
  3. Jan 29, 2008 #2

    Q_Goest

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    A throttling valve doesn't reduce pressure, it is simply a restriction in the line. It will serve the purpose of reducing pressure if the flow rate is constant, upstream pressure is constant, and there is some inherent feature in the system which compensates for minor variations in flow. Without knowing what your system looks like however, it's best not to speculate on whether or not a throttling valve would work.

    There are many manufacturers of very low pressure regulators. I'd suggest looking into Fischer to start.
    http://www.fisherregulators.com/
     
  4. Jan 29, 2008 #3

    Mech_Engineer

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    You should also do a search on www.globalspec.com based on your specific requirements to see if anything turns up.
     
  5. Jan 29, 2008 #4

    Danger

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    Would running a couple of regulators in series do it?
     
  6. Jan 29, 2008 #5

    stewartcs

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    No, it has to be designed for low pressure applications.

    CS
     
  7. Jan 29, 2008 #6

    Danger

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    Sorry, then, pal. I know nothing about this; I was just throwing in my 2 cents. Times like this, I really wish that I had an education.
     
  8. Jan 29, 2008 #7

    Mech_Engineer

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    He's only trying to reduce 50 psi to around 0.5 psi, so 2 regulators in series wouldn't really be necessary. I did a search on GlobalSpec and found many regulators that have adjustment ranges similar to the OP.
     
  9. Jan 29, 2008 #8

    FredGarvin

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    Depending on the fluid and the flowrates, there are indeed a lot of vendors that make applicable regulators. If it is a relatively low airflow requirement (when compared to large industrial applications), look at someone like Fairchild regulators or, for a more expensive but very nice regulator, look at Tescom.
     
  10. Feb 9, 2008 #9
    Actually a throttle valve may work if you need to fill a vessel up to a specific pressure and the regulators output pressure is to high you can slow the fill rate down and more accurately fill your application. you will need a separate pressure transducer downstream of the throttle valve probably about 0-100 torr. The fact that you need sub-atmospheric pressures makes me believe you are probably not dealing with a continuous flow device.

    swagelok makes good products just don't use the brass ones!!
     
    Last edited: Feb 9, 2008
  11. May 21, 2008 #10
    also take look to parker products. similar to swagelok

    Rick
     
    Last edited by a moderator: May 21, 2008
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