Why Choose a LobePro Positive Displacement Rotary Lobe Pump instead of a Centrifugal Pump?
LobePro pumps are effective replacements for centrifugal pumps in sludge and slurry applications because they are more forgiving. Centrifugal pumps are adversely affected by entrained air, inadequate Net Positive Suction Head (NPSH) or by not operating within 10% of their best efficiency point (BEP). In contrast, our pumps will happily pump air and water, have low suction requirements and operation at any points within their operating range is fine.
According the Hydraulic Institute there are 13 advantages of positive displacement ( PD) pumps over centrifugal pumps. The Hydraulic Institute is not alone in this assessment. Leading textbooks say the same – for example the following:
“Use of centrifugal pumps is restricted in most common cases to relative dilutes (less than 1% solids, trash free solids.)”
– Wastewater Treatment Plant Design by P. Arne Vesilind Chapter 12
Here is a quick review of PD Advantages over Centrifugal Pumps:
1. Advantages of almost all PD Pumps including LobePro:
- Can provide a constant flow at different pressures or constant pressure at different flow rates.
- Low fluid shear
- Can pump a mixture of air and fluid successfully.
- Are generally much more energy efficient than centrifugal pumps because of the low amount of slip.
2. Advantages of LobePro which many PD Pumps do not share:
- Superior for pumping sludge, mud and thick fluids.
- Can handle abrasives well because of slow speed and because lobes do not touch.
- Can run dry for a period of time because seals are oil cooled and lobes do not touch.
- Flow is near pulseless because of the helix lobe design.
- Can self prime to 25 ft with strong vacuum.