Adjust LPM in my pump. 2

[freeland90]

Hello,
My pump is rated for 5-30 LPM. However, the system I'm using only requires a flow of 5 LPM. What are the ways to make sure my flow remains at 5 LPM knowing that my pump is a plug and play? No switches.

 

[Valvecrazy]

1.3 GPM Dole valve.

 

[LittleInch]

A control valve of some sort (globe or needle).

But what type of pump? That would work for centrifugal, but PD you need to control the speed.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[TugboatEng]

Is the pump positive displacement or centrifugal?

 

[Artisi]

Is this the same pump as the viton ring post?

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[freeland90]

Thanks for all the replies. Yes Artisis, is it the same pump described here:

https://www.eng-tips.com/viewthread.cfm?qid=490106

Please let me know.

 

[LittleInch]

As above.

If you get lucky a fixed orifice plate might be used, but valves are infinetly variable.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[freeland90]

Thanks, Little Incy, Appreciated it. If my pump was centrifugal. It would have been equipped with a way to reduce flow, right? What would have been the option then? VFD?

 

[LittleInch]

Your pump IS centrifugal.

If your pump was positive Displacement (PD) then to vary flow you vary RPM or stroke length if you can.

See the thread next to yours in the pump forum for the same question but this time the OP has a PD pump.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[freeland90]

Hey LittleInch!
Please bear with me. How can you tell the difference? It's my understanding that a centrifugal pump has an impeller, my untrained eyes thought that any pump with a circular large shape on it is centrifugal.

 

[Valvecrazy]

Yeah I think that is what they call a "peripheral" pump. Sort of positive displacement, so amps will go up with a restriction. You will either need to vary the speed or pump into a pressure tank and just draw 5LPM as needed. A centrifugal pump would be much better and a simple valve would give you 5LPM.

 

[LittleInch]

Indeed it seems it is a peripheral pump - never seen one before really and I suppose it's a mixture of a centrifugal pump and a PD.

The pump curve is quite interesting as it slopes down at a near constant angle so the head at low flow is high but at max flow is quite low.

So yes it will use more power, or maybe the same power at lower flow, but you can still control it with a valve.

Yours is curve 1 on the below.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Artisi]

Without getting too involved with sourcing data that the OP should be supplying, it looks like a regenerative turbine pump, it follows the rules of a centrifugsl pump regrading speed change etc, Good for low flow, high head - fits well for flow / pressure between small centrifual and PD pumps.

What's the next question, can I change the pump colour?.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[Artisi]

Freeland90, do your untrained eyes a favour, plenty of material on the net for untrained

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)