Need a pump that satisfies these conditions

[skaboy607]

Hi

I need a pump that satisfies these criteria. I need to pump water at volume flow rate of 0.6 l/min. Pressure in the system to overcome in just over a 1m.

I have a pump but it has a max flow of 16 l/min and although it is linked to a valve, I feel that would I have to restrict the flow too much and risk causing a temperature increase in the fluid which is not possible.

Thanks

 

[SNORGY]

If your Design Code allows (whatever design code applies to your system) you might look at a laboratory-grade syringe pump, although it would likely occupy a disproportionate amount of space.

Regards,

SNORGY.

 

[skaboy607]

I think these will be a bit too expensive. I thought about using a pump that is used in watercooling CPU chips in computers but the max temperature they will operate too is 60C and I think this setup might get to 80 ish.

 

[TenPenny]

I think you might need to look at a peristaltic metering pump.

 

[cvg]

re-circulating pumps might work. cheap and durable, here is an example :

Grundfos Hot Water Cast Iron Circulator 10 GPM 3-Speed # UPS15-58F

http://store.waterpumpsupply.com/5gpminhotwat1.html

 

[skaboy607]

Oh ok, thanks. I have also found this pump:

http://www.coleparmer.co.uk/catalog/product_view.asp?sku=0701220

Trouble is, it says that there is no max head associated with gear pumps and this is where my knowledge of pump sizing falls down.

How can I see if this is pump is suitable?

 

[cvg]

you need at least two points on the pump curve, preferably three in order to size a pump. for instance, the 10 gpm grundfos example above on speed 1 would actually deliver your design flow of .16 gpm with just a bit of throttling

contact the dealer
Grundfos UK - SalesTelephone: 01525 850000
Website:

http://www.grundfos.co.uk

 

[btrueblood]

A gear pump will deliver volumetric flow proportional to shaft speed with very little slip, up until either the motor stalls or something breaks, or the gears and endplates wear to the point that leakage increases substantially.

The particular link you posted states quite clearly:

"Max pressure 21 psi"

Probably limited by stall torque of motor.

 

[skaboy607]

That wasn't the question I was asking but an interesting insight anyway so thanks.

I was only asking what the difference is between the max head quoted on centrifugal pumps and the max pressure quoted here, as it indicates clearly further on down the page that gear pump specifications do not provide a max head.

 

[btrueblood]

They mean that the max. delivered head of a gear pump is not controlled by the pump design, but must be limited by other means (pressure control valve, torque limit of motor/driver, etc.). The max permissible head delivered IS a function of the pump design, and you exceed that head at your peril. They do mention in the comments area that "exceeding the 21 psi max head may damage the pump", so it sounds like the motor may not limit the head after all...

 

[btrueblood]

By the way, it's something I really hate about Cole Parmer, that an important spec. like that is buried in a comment, not made clear in the catalog page itself.

Also, you may be able to locate the OEM for that pump, with a bit of searching, and easily shave 50% or more off the CP price, especially if you have volume numbers to talk about. I've had pump manufacturers give me loaner samples to prototype with, based on a possible future volume in the 100's of units per year.

 

[skaboy607]

Ok thanks for the tip.

So if I understand correctly, the two are still linked, just one is controlled by pump design the other isn't. If I know that the pressure losses in my system are greater than the 21 psi quoted, then I know the pump is no go.

Yea Cole Parmer have not been my friends the last few years, looking like the Grundfos pump 'cfg' posted is a winnera at the moment.

 

[btrueblood]

"If I know that the pressure losses in my system are greater than the 21 psi quoted, then I know the pump is no go."

Um, yes. But there are many other manufacturers and each has many other pump designs. Keep looking.

 

[skaboy607]

Sorry I meant 'that' pump is a no go.

 

[ACCESSUSA]

See if any of these work for you:

http://www.grainger.com/Grainger/ecatalog/N-/Ntt-metering+pumps?itemsPerPage=60

AC

 

[stanier]

Have you investigated a peristaltic pump?

"Sharing knowledge is the way to immortality"
His Holiness the Dalai Lama.

http://waterhammer.hopout.com.au/

 

[ports394]

The Coleparmer gear pump are really nice.

http://www.coleparmer.co.uk/catalog/product_index.asp?cls=20287

I have 2 in my lab. But it's somewhat unpredictable, because you're relating PSI on the air regulator to flow rate. (Hint, install a good flowmeter... from McMaster), and you'll like the setup a lot. It's a bit noisy. the air outlet is 1/8" NPT. I bought an air sparger/muffler from McMaster for $5 in stainless steel, and it does a good job of reducing the noise.

I also have a masterflex peristaltic pump I bought on eBay for $150. That is also a really nice, accurate pump.