Pumps for high viscous fluids
Pumps for high viscous fluids
(OP)
For context:
I'm currently upgrading a pump for Low Sulphur Waxy Residue- the existing pump is a centrifugal pump with the following parameters (rated):
Is there a rule of thumb/threshold for viscosity where a screw pump would be preferred over a centrifugal pump?
I'm currently upgrading a pump for Low Sulphur Waxy Residue- the existing pump is a centrifugal pump with the following parameters (rated):
- Q = 70 m3/hr
- h= 160m
- viscosity at pumping temp (83 degC)= 10.2 cP
- density of fluid at pumping temp: 875 kg/m3
- Q2= 120 m3/hr
- h2= 250m
Is there a rule of thumb/threshold for viscosity where a screw pump would be preferred over a centrifugal pump?





RE: Pumps for high viscous fluids
RE: Pumps for high viscous fluids
We have looked at centrifugal pumps for pumping waxy Crude Oil which has cP of 60-100 without an issue, so 10 is fine. If the current one works OK, why change pump type just because flow and head has gone up?
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Pumps for high viscous fluids
Littleinch, the pumps are working fine and probably wont' be changed (as you mentioned, only the head and flow have increased). Just checking if there's a rule of thumb for pump selection- thanks for your input, much appreciated.
RE: Pumps for high viscous fluids
In the process world your viscosity isn't very high so you are still good.
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P.E. Metallurgy, Plymouth Tube
RE: Pumps for high viscous fluids
One of the main issues will be the reduction in efficiency, which can be drastic, and many times require an oversized motor.
You then should balance the overall cost against using a positive displacement pump.
RE: Pumps for high viscous fluids
The guideline is that for the viscosity above 65 centistokes, rotary or reciprocating pumps are recommended.
However, as discussed above, it's depended on the application, condition and equipment design.
The 65 centistokes is just for a general guideline which shall be verified/considered when you received the pump curve/data sheet from vendor.
RE: Pumps for high viscous fluids
Thanks again all.