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General Forestry => General Board => Topic started by: brendonv on April 07, 2015, 12:34:13 PM

Title: Hydro power pack calculations.
Post by: brendonv on April 07, 2015, 12:34:13 PM
Trying to save a buck putting together my own power pack for a loader. They will sell me a 2400 psi, 7gpm setup for north of 2500$.

Can anyone suggest in pointing me in the right direction for calculating the correct pump for a 13hp Honda?  Or even a 9 hp honda that brings me near 7gpm and 2400 psi?

I'm thinking I can save a grand. Engine 900, pump and mount  200, hoses 25, tank free, metal frame work 40, battery 25.
Title: Re: Hydro power pack calculations.
Post by: Dave Shepard on April 07, 2015, 04:17:35 PM
Does Surplus Center have any calculators in their website? I think rule of thumb is 1hp per gallon per 1, 000 psi, but I may be off on that.
Title: Re: Hydro power pack calculations.
Post by: brendonv on April 07, 2015, 04:35:29 PM
Ya they work great. I just need help/guidance choosing the right pump.
Title: Re: Hydro power pack calculations.
Post by: brendonv on April 07, 2015, 05:14:33 PM
The 7gpm and 2400psi are loader requirements. I mighta worded the above wrong.
Title: Re: Hydro power pack calculations.
Post by: NWP on April 07, 2015, 06:46:31 PM
http://www.surpluscenter.com/Tech-Help/Hydraulics/Pumps-Motors/

This looks like it might be what you're looking for.
Title: Re: Hydro power pack calculations.
Post by: snowstorm on April 07, 2015, 07:26:28 PM
would a 9hp honda  8gpm parker pump 5gal tank all bolted togather work?$1900 hamilton marine.com  they use them to power pot haulers on lobster boats
Title: Re: Hydro power pack calculations.
Post by: brendonv on April 07, 2015, 08:54:59 PM
Thats only 1700psi.

I think i need around a .50 cu pump. Going to look into it more.
Title: Re: Hydro power pack calculations.
Post by: Brucer on April 08, 2015, 12:29:52 AM
To size the motor ...
Fluid HP = USGPM x PSI / 1714.
The pump will typically run at 85% mechanical efficiency, so you need to adjust this ...
Mechanical HP = Fluid HP / 0.85 (for direct drive arrangements).

If you already have the motor, change this around.
Fluid HP = Mechanical HP x 0.85
USGPM = Fluid HP x 1714 / PSI.

To figure out what pressure you need, calculate how much force your cylinder has to apply to lift the heaviest load you want to lift.

  PSI = Force / Piston area (square inches).

If you know the force and you know the maximum pressure you can handle ...

  Piston area = Force / PSI.