gear pump question.

[wedge40]

I have a pump with the following specs that I want to mount on my tractor. It'll be ran off the crank shaft on the front of the tractor. What I want to know is if I only run the tractor at 1500 rpm will the gpm be less than 14.6? If so is there a way to calculate what the flow rate would be? I'm guessing it wont be linear.

Wedge

EATON/CESSNA GEAR PUMP

Brand new EATON Model 26000. Replaces Cessna 26300 Series. Hydraulic gear pump. Ideal for replacement on mobile equipment and other hydraulic systems.

SPECIFICATIONS

* 3000 PSI max
* SAE A 2 bolt mount
* Side ports: IN SAE 16, OUT SAE 10
* Shaft 3/4" dia x 1 1/4" w/keyway
* CCW rotation



* 1.87 cu in displ/rev
* 3000 max RPM
* Rated GPM at 2500 PSI:
* 24.1 @ Max RPM
* 14.6 @ 1800 RPM
* Shpg 7 lbs

 

[3RRL]

What I want to know is if I only run the tractor at 1500 rpm will the gpm be less than 14.6? If so is there a way to calculate what the flow rate would be?
Yes, it will be less than 14.6GPM since that's what it puts out at 1800rpm.
It will be 12.14 GPM.
1 cu/in =.004329004 gallons so 1.87= .008095238 gallons.
1500rpm x .008095238 = 12.142857 GPM

 

[wedge40]

What I want to know is if I only run the tractor at 1500 rpm will the gpm be less than 14.6? If so is there a way to calculate what the flow rate would be?
Yes, it will be less than 14.6GPM since that's what it puts out at 1800rpm.
It will be 12.14 GPM.
1 cu/in =.004329004 gallons so 1.87= .008095238 gallons.
1500rpm x .008095238 = 12.142857 GPM

Thanks Rob, I've gotten lazy in my old age.. I should have been able to figure this out myself. Simple math. 231 cu in a gallon.

Hmm Now I think I might have too big a pump.

Wedge

 

[3RRL]

Thanks Rob, I've gotten lazy in my old age.. I should have been able to figure this out myself. Simple math. 231 cu in a gallon.

Hmm Now I think I might have too big a pump.

Wedge

Hahaha, me too and surprised one of the whippersnappers didn't beat me to it.
Why don't your just run it at 1800rpm if you need that flow?
It might be right in the good torque range of your motor?

 

[wedge40]

Why don't your just run it at 1800rpm if you need that flow?
It might be right in the good torque range of your motor?

Thats the problem, I'm really looking for somewhere between 9 and 12 gpm. I might end up getting a little smaller pump. Right now I'm using the pump off the tractor, which is 5 gpm, and when I get this done I dont want it so fast that as I raise the loader I'm toss dirt into the air as it hits the end of travel. But it will be nice to have the extra umph for additional valves.

Thanks again.

Wedge

 

[3RRL]

Oh sorry, I was thinking you needed more flow at lower rpm.
But if you already have the pump, just run it between 1112rpm (9GPM) and 1482rpm (12GPM) then, instead of buying a new one. That would work, right?