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Vacuum Pump Selection

  1. Sep 6, 2008 #1

    I need some help selecting a vacuum pump.
    Required specs

    - 5 CFM
    - vacuum (0-10 in/mg)
    - possibility of sucking up small metal particles (size:50-200 microns)
    - working fluid is argon/air
    - needs to handle high heat

    My original feeling was to go with a venturi design made my FESTO. But I don't like the idea of wasting compressed air.
  2. jcsd
  3. Sep 7, 2008 #2
    Do you mean 0-10 inHg? (http://en.wikipedia.org/wiki/Inch_of_mercury" [Broken]). When you talk about vacuum pumps it is the zero part in the 0-10 that makes all the difference. How close to 0 does your vacuum need to be.

    There are different gradations in vacuum:

    Atmospheric pressure 760 Torr 101.3 kPa
    Low vacuum 760 to 25 Torr 100 to 3 kPa
    Medium vacuum 25 to 1×10-3 Torr 3 kPa to 100 mPa
    High vacuum 1×10-3 to 1×10-9 Torr 100 mPa to 100 nPa
    Ultra high vacuum 1×10-9 to 1×10-12 Torr 100 nPa to 100 pPa
    Extremely high vacuum <1×10-12 Torr <100 pPa

    For medium vacuum you can use a roughing (positive displacement, rotary vane) pump. http://www.varianinc.com/cgi-bin/nav?products/vacuum/pumps/index&cid=KKKLPLPJFO".
    Last edited by a moderator: May 3, 2017
  4. Sep 8, 2008 #3


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    I would highly recommend that if you are not used to spec'ing out a pump yourself that you go through a supplier that can size one for you. Especially with vacuum pumps. Look for your local reps under something like ThomasNet.
  5. Sep 8, 2008 #4
    Thanks for the help,
    I should have clarified myself better, What I was looking for was 0-10inHg gauge pressure This leaves me well into the low vacuum region.
  6. Sep 8, 2008 #5
    If you want to get to low vacuum and your chamber has a relatively small volume you should use a roughing pump to back up the turb-mech pump. Also try the company Lybold (I think it is spelled correclty) located in Delmont, PA.
  7. Sep 8, 2008 #6


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    A turbo pump is overkill. He only needs 10 inHg gauge pressure, which is around 20 inHg or 500 Torr absolute pressure.
  8. Sep 23, 2008 #7
    10 inHg Vac = 254 mmHg Vac = 506 Torr = 674 mbar = 67.4 Kpa

    this is a depression, but not really to be considered as a vacuum.

    Also 5 cfm (8.5 m³/h) is very small for a mechanical pump: you original idea of an air driven ejector is probably the best solution. If compressed air is not available you may look for a mini liquid ring vacuum pump.

    Manufacturers for ejectors and vacuum pumps are listed in www.vacuum-guide.com
  9. Sep 12, 2009 #8
    i need some help also in choosing a vacuum pump. i am currently in the process of manufacturing small plastic parts. a serious problem i need to fix is the air bubbles trapped within the resin compounds, thus resulting in a flawed final project. i am new to the degassing/vacuum chamber world so forgive my lack of knowledge in this field. i do not need a massive pump for i am only degassing no more than 5 fl oz of resin with a viscoscity around 500 cps with the possibly of up to 2000 cps. i was looking at a vacuum pump made by Robinair product id rob15800 with a 8cfm rating. i was thinking of linking it up to a vacuum chamber to perform the degassing. i wanted to see if a that company was any good and if that pump would do the job, and b if anyone has a better suggestion...any help would be much appreicated. thank you for your time
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