Pump question.

[desert trader]

I came across a 540 hydraulic pto gear pump that had been reduced at the inlet from 1 1/2" to1" and reduced at the outlet from 1 1/2" to 3/4" and I guess they were trying to reduce the gpm. The pump is a Gresen Minniapolis ,there is a number 096 on the front and an A3 on the bottom.I'm guessing the pump to be 40 gpm.
My question is can you reduce the gpm this way without causing some sort of problem?

 

[rdbrumfield]

Wouldn't recommend it. The pump is designed to flow with the ports it has on it. By reducing incoming oil it will cavitate and reducing outflow will cause excessive pressure and heat.

 

[sizzami]

many pumps are used in multiple applications and are ported to plumb into the largest, that reduction should be fine also remember these pumps are rated at optimum flow in optimum conditions , 40 gpm through 1.25 is reasonable as long as your resivoir is big enough , thats my two cents.

 

[J_J]

I came across a 540 hydraulic pto gear pump that had been reduced at the inlet from 1 1/2" to1" and reduced at the outlet from 1 1/2" to 3/4" and I guess they were trying to reduce the gpm. The pump is a Gresen Minniapolis ,there is a number 096 on the front and an A3 on the bottom.I'm guessing the pump to be 40 gpm.
My question is can you reduce the gpm this way without causing some sort of problem?

Probably would not affect it very much. If you are trying to get every little bit from that pump, maybe see a small reduction in volume, and maybe a small pressure differential. Nothing major.

A lot of times when building or replacing a system or part of a system, you have to use common sense. If the reservoir has 1 in fitting, and the pump has an input fitting of 1 1/2 in, what are you going to do. If the motor has an input of 3/4 in, and the output of the valve is 1 in, what would you do. Just make do with what you have. There are flow charts available to give you an idea of the proper hose/fitting to use with the GPM's

And you should all know that smaller diameter hose usually has a much higher pressure rating. The larger hose , will usually decrease the pressure rating, unless it is a specialty hose.

In using QD's, common sense tells you there is going to be some restriction in the QD's, and maybe slow down the flow, so the logical thing to do is go up one size for the QD's.

 

[Egon]

And you should all know that smaller diameter hose usually has a much higher pressure rating. The larger hose , will usually decrease the pressure rating, unless it is a specialty hose.

How do you define "Large or Small" :confused2:

The pressure rating of the hose is quite independent of the apparent size. It is what the hose, regardless of size, is designed for.

For the OP he should contact the pump builder and get some accurate information.:thumbsup:

 

[J_J]

How do you define "Large or Small" :confused2:

The pressure rating of the hose is quite independent of the apparent size. It is what the hose, regardless of size, is designed for.

For the OP he should contact the pump builder and get some accurate information.:thumbsup:

1/4 in Small. 1 in large