GPM by RPM for Pumps

[NJWashingGuy]

If a General TS2021 does 5.6 GPM at 1450 RPM, What RPM must it spin at to produce 5.0 GPM??

If a General TSF2421 does 10.0 GPM at 1450 RPM, what RPM must it spin at to produce 8gpm??

I get confused with all the math...... thanks in advance for any help!
Mike

 

[Tim Mcculla]

uhhhhh....less, yea less than 1450 RPM.

Do I get a prize for the first correct answer?

Just Kidding, I have no idea how to figure that out.

 

[RGilliam]

1150 for the tsf2421 if I had to guess.

 

[RGilliam]

1300 for the other? I dunno if im right, maybe Russ will chime in!

 

[Russ Johnson]

RPM divided by gpm times desired gpm equals target rpm.

1450 / 5.6 = 259
259 X 5 = 1295

1450 / 10 = 145
145 X 8 = 1160

 

[RGilliam]

so 1150 and 1300 huh? Man im good!

 

[NJWashingGuy]

RPM divided by gpm times desired gpm equals target rpm.

1450 / 5.6 = 259
259 X 5 = 1295

1450 / 10 = 145
145 X 8 = 1160

Thanks Russ, Ron good guesses!

 

[Johnson]

Riddle me this.....do you have to change pulleys to change rpm's?
If so then what size?
I already know what I need to change them with.....

 

[RGilliam]

It depends on what speed you want your pump to spin.

 

[NJWashingGuy]

Riddle me this.....do you have to change pulleys to change rpm's?
If so then what size?
I already know what I need to change them with.....

Yes, pulley diameters on the pump and engine determine rpm based upon rpm of the motor. Threre is an equation for rpm, but i think the ratio is like 2.2 to 1 based upon 3400 rpm because thats about what the motor should be doing under load. I am sure that Russ could give better insight.