Pump run with high Viscosity liquid

[wangduyu]

Dear all,

We have a pump for hot oil with Dynamic viscosity 0.55mPa.s in 220C, for cold test run, we will have cold oil with Dynamic viscosity 8.12mPa.s.

Vendor information shows that when Dynamic viscosity is less than 20mPa.s, it will be ok. I wonder where it comes the conclusion of 20mPa.s.

May I have the answer?

Thanks.

 

[LittleInch]

What type of pump?

I suspect this is just something they have found with experience that their particular unit doesn't work well above that limit.

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

 

[wangduyu]

it is ITT centifuge pump, with head 44.8m, flow rate 5m3/hr, oil density similar to water.

I also think it is an experience value, coming maybe from experiment. how to prove it to client is a question.

 

[BigInch]

Basic theory of the effect of high viscosity on centrifugal pumps you will find here,
show your client where you are on the charts.

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

 

[wangduyu]

Thanks, LI and BI, powerful evidence.

 

[itdepends]

It's a rule of thumb. I would not expect to see any difference between the performance of the pump under those two conditions.

As a chem eng/metallurgist the first part of any answer I give starts with "It Depends"