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HELP on hydraulic system design

HELP on hydraulic system design

HELP on hydraulic system design

I have a hydraulic design problem.
There are two hydraulic pipelines, two pumps: one being driven by electric motor, the other by a human by peddling.
I need to join both the flows in one. Both pipes have non-return valves at the end.
The problem is, the pressure by electric motor pump is high(30 bars) and human peddling can't create that much pressure, so the non-return won't allow the flow to go through. Is there any way to increase the pressure or accumulate it(any device that could be helpful).  

RE: HELP on hydraulic system design

Increase the common outlet piping size to reduce pressure.  Reduce electric motor-driven pump to reduce flow.

Reduce the size of the human powered pump to allow human to be able to deliver against higher pressure.


RE: HELP on hydraulic system design

but I need to maintain the output piping pressure to be 30bar.
is it feasible to let the human keep peddling and let the pressure increase to 30bar so that it pass through(though slow but it will work, right?)

RE: HELP on hydraulic system design

It is difficult to pedal against the 30 bar pressure because the pump driven by the bike has to generate enough torque to provide 30 bar at the displacement of the pump.

You can either change the gear ratio on the bike or deliver less fluid from the pump.

RE: HELP on hydraulic system design

can't i use any device to increase the pressure?
i read about some, pressure booster on the net.
can that work?

RE: HELP on hydraulic system design

Pressure boost devices are really for static systems where flow is minimal, such as clamping systems.

You can use any sort of pressure intensifier that you can find. However, you seem to want a combination of pressure and flow.

For the amount of power available from the bike, you can have pressure, or you can have flow...you can't have both.

Without increasing the time, or reducing the flow, or dropping the pressure. The only way to get what you need is to increase the power available...that means get 2 bikes!!!

RE: HELP on hydraulic system design

so, is it even possible to do what i am trying to so?
any other suggestions or changes on how to make it work?

RE: HELP on hydraulic system design

It would be helpful for you to describe in detail what you are trying to accomplish.


RE: HELP on hydraulic system design

Yes, pretty much.

You are trying to rewrite the laws of physics.

You can reverse the sprockets on the bike, you will be able to generate the pressure, but the flow rate of the pump will drop off. It would be like changing the gear ratio. Whoever pedals the bike would have to go really fast, but the pressure would be build slower.

The same amount of energy would be used, but over a longer time period...so the power would be less.  

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