Centrifugal vs jet for pressure boost

[Alternety]

I have a critical need for a replacement pump. My direction is a multi-stage centrifugal pump. It has been suggested that I use a jet pump instead.

Configuration:
External bulk storage tank. Bottom at about the height of the pressure pump intake (e.g., zero head to overcome).
Pump sits in the basement.
Large pressure tank capacity.
Required pressure in the system - 40/60psi.
Desired capacity around 25 gpm at pressure.
All Stainless Steel in contact with water.
120/240 single phase.
Pump in bulk tank or changing pipe size not feasible.

All of the research I have conducted seems to show jet pumps have a rather weak curve around 60psi. Centrifugals I have selected do not.

Is there some reason to use a jet instead of a centrifugal in terms of performance or efficiency?

 

[Craigpump]

Centrifugal pumps won't make 60 psi

 

[Sponsor]

 

[LLigetfa]

I think he's talking about the multistage pumps that are essentially the wet end of a submersible.

 

[Alternety]

Yes. That is the type of centrifugal I am talking about. The jet pumps exist in that range. A Goulds J15S pretty much gets there but with a rather steep drop off in volume at 60psi.

 

[Craigpump]

My bad

 

[Valveman]

With a 40/60 pressure switch the only reason the pump even needs to build 60 PSI is so the pressure switch can shut it off. There is no need looking at the pumps performance at 60 PSI if that is where the pressure switch shuts it off.

A 40/60 pressure switch gives you an average of 50 PSI. But it also says that 40 PSI is sufficient, or you couldn’t let it go that low before the pump is started.

Look at the performance curve between those two pumps at 40 PSI (92’) and 50 PSI (115’) and you probably won’t see much difference. Jet pumps work great as booster pumps until the required pressure gets higher than about 60/70 PSI.

It is also a good thing that the flow rate drops off dramatically at 60 PSI. This is working a little bit like a CSV as it will reduce the number of pump cycles compared to a pump that doesn’t drop off at 60 PSI or so.

 

[Alternety]

I want to be able to generate those volumes at that pressure. See my thread "
Need a pump very quickly" for more detail.