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Two Pumps on one system flow question

  1. Dec 7, 2016 #1
    I am hoping this is the right place to post this.
    I have a hydraulic system that uses two pumps. Each pump is capable of producing 22.5 gpm. With out taking into account the different valves, restrictors, and pipe sizing, my question is, does my gpm double to 45 gpm or stay at 22.5? the pumps are not in line with each other, just provide fluid flow and pressure to the same system.
    the way I was taught was I only have the 22.5, recently some guys have been saying we have 45. I cant find any laws or theories to explain this. thank you for all the help
  2. jcsd
  3. Dec 7, 2016 #2


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    These are positive displacement pumps ?
  4. Dec 7, 2016 #3
    Yes positive displacement. the pumps are self compensating, variable volume. at max demand each pump can produce 22.5 gpm
    Last edited: Dec 7, 2016
  5. Dec 7, 2016 #4


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    What is the controlling element (i.e. flow, discharge pressure etc) that provides the demand signal to each pump?
  6. Dec 7, 2016 #5
    As the pressure drops in the system the pump will self-compensate for the increased demand.
    I think I have found my answer to the original post. Running the pumps in parallel is going to give me a greater flow than just 22.5 gpm as long as they are operating at the same pressure. which in this systems both pumps operate at 3,000 psi. any additional thought would still be appreciated.
    This website really helped.
  7. Dec 7, 2016 #6


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    Basically, the two pumps will act in concert to deliver up to a combined maximum 45 gpm @ 3000 psi system delivery demand level.
  8. Dec 8, 2016 #7


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    Yes, that's an excellent site...
    Another good one is... here .

    I've always considered it somewhat strange, that anybody would want a pump or motor that was... bent !

    Just kidding... :oldwink:
    Last edited: Dec 8, 2016
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