Viscosity correction for liquid

[AKVS24]

What should be the minimum viscosity of pumping liquid to use Viscosity correction chart?What is its significance?

 

[1gibson]

1) Wherever the chart starts, I would guess 15cSt or so
2) There will be correction factors for head, flow, and efficiency (Ch, Cq, Ce).

Low viscosity will only have a significant effect on efficiency. As you increase, it will require correction to head and flow as well.

The significance? You need a bigger motor and maybe bigger impellers

 

[bimr]

I assume that you are inquiring about centrifugal pumps. As shown on the link, small increases in viscosity have a significant effect on pumping rate and efficiency.

http://www.pumpschool.com/intro/pd vs centrif.pdf

The pump manufacturer is the best source to answer the question for a particular application.

 

[Pumpsonly]

The HI has a chart for viscosity correction on centrifugal pump performance. The effect is more significant for small / low specific speed pump.

 

[BigInch]

that link is for micropumps.
See the HI info.
Small low SS pumps have a problem getting enough fluid into them t pump it. For pipeline centrifugal pumps, 500 cP is more like it.

What would you be doing, if you knew that you could not fail?

 

[clay87]

I always end up here:

http://www.mcnallyinstitute.com/14-html/14-04.htm

 

[PumpSmart]

AKVS24,
You will use the chart or you will use polinomial form to calculate those correction factors.

Polinomial form are publisehd on:

http://www.warrenpumps.com/brochures/Fluid Viscosity Effects.PDF

In industrial centrifugal pump, corrections factor will be negligible for lower values than published on chart, you are able to check this with polonomial form.

HI, has a new method to calculate corrections factors.
Nomograph is not used any more.

I hope this helps.