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Low flow and high head! OH6 or a Reciprocating Pump?

Low flow and high head! OH6 or a Reciprocating Pump?

Low flow and high head! OH6 or a Reciprocating Pump?

(OP)
In the following condition:

Diff. Head = 270m
Rated Flow= 14.3 m3/hr
Viscosity= 0.2027 Cp

I've selected OH6 pump but a friend of mind said a reciprocating pump may also meet these conditions.
Is there any preference (technical of economical) to choose between these two types of pumps?

Thank you all!

RE: Low flow and high head! OH6 or a Reciprocating Pump?

A reciprocating pump is for sure more expensive but probably more efficient, too. It would be good to know what fluid shall be pumped to give any advice.

RE: Low flow and high head! OH6 or a Reciprocating Pump?

That is fairly low pressure for a reciprocating pump selection; typically think of PD pumps when pressure gets near/over 500 psi. The flow (>40gpm) means it won't be a small recip either. PD's usually are low flow, high head, pressure builders. From what you've shown, this seems to fit a centrifugal better......

The more detail you give, the better answer you will receive; and vice versa.

WOuld be helpful to see:
fluid, SG, solids?, temp, lots of starts/stops?, etc.

RE: Low flow and high head! OH6 or a Reciprocating Pump?

For me it really depends on your service and operation. If your flow is fixed but pressure can vary a bit then pd is good. If you've got variable flow, then unless you want to instal vfd motors on your pd pump, then you need recycle lines to avoid high pressure and vary the flow.

All in all at these sorts of head and flow I would go for a centrifugal unless you have big variations in head

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

RE: Low flow and high head! OH6 or a Reciprocating Pump?

(OP)
Thank you all for your responses!
In this case the pressure isn't variable and it seems that Cent. pump is a better choice.

RE: Low flow and high head! OH6 or a Reciprocating Pump?

There seems to be general agreement that a centrifugal pump is probably a better choice for your service. But, there has been no reference yet to the OH6 selection. I would not prefer an OH6 but would rather have a multi-stage pump. The pressure is not very high and the flow rate should be in the range for a stacked rotor, multi-stage pump. We have similar pumps in wash water service at 90 gpm and 1000 psi. These tend to be more reliable and have higher efficiency than other wash water services that use high speed, integrally geared pumps running at 15,000 rpm or more.

I only used OH6 when absolutely necessary.

Johnny Pellin

RE: Low flow and high head! OH6 or a Reciprocating Pump?

(OP)
Thank you Mr. Pellin for your advice!
I thought that between bearing pumps are generally large and are used when the capacity and head are high.
You mean that BB1, BB2, BB3 or even BB5 could be used for low flow? (like 40~60 gpm)

RE: Low flow and high head! OH6 or a Reciprocating Pump?

Thinking in Centrifugals.
MultiStage Radial Section or Ring section called BB4 with acceptable effy of 40%.
OH2LF - Low Flow could do it, but very low effy , around 12%.

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