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Can I get a 40KN force from a hydraulic cylinder powered by an electric motor?

  1. Dec 5, 2012 #1
    Im thinking of designing a tipping trailer for a car. I need a force of 40KN exerted to tip but would this be too much for driving with an electric motor powered by the car battery. If not what size of motor and pump would I need? thanks
  2. jcsd
  3. Dec 5, 2012 #2


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    With hydraulics, you can get absolutely any force with absolutely any power input. You can hand-crank 40kN with hydraulics. In fact, I'm pretty sure you could find a hydraulic car lift that does just that.

    Now, if you have a force, say these 40kN, and the time in which you want to raise the load a certain distance, you can get power. Say you want to raise 40kN load 1 foot in 1 minute. That works out to roughly 200W. Factor in loses, both mechanical and electrical, and you are probably looking for a 300-400W motor. At 12V, that works out to something in the 25-35 amp range. You should be able to draw that from a car battery.
  4. Dec 5, 2012 #3
    Thank you for reply, very helpful
  5. Dec 7, 2012 #4


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    Just for completeness the equation K^2 is using is ..

    Power = Force * velocity = force * distance/time

    Force in Newtons
    Distance in Meters
    time in seconds
    Power in watts

    If drawing 25A think about the wire guage needed and use appropriatly rated switch and fuse. A standard 30A rated switch might not last very long as the startup current could be much higher than 25A.

    Perhaps assume the motor is only 60-80% efficient? The pump?
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