of air into an engine's intake manifold - then pressure is created in the discharge space. A lobe pump itself does not compress the material it pumps. Lobe pumps are frequently used in food applications because they handle solids without damaging the product. Particle size pumped can be much larger in lobe pumps than in other positive displacement types. Since the lobes do not make contact, and clearances are not as close as in other Positive displacement pumps, this design handles low viscosity liquids with diminished performance. Loading characteristics are not as good as other designs, and suction ability is low. High-viscosity liquids require reduced speeds to achieve satisfactory performance. Reductions of 25% of rated speed and lower are common with high-viscosity liquids. See also Positive displacement pump Roots blower Gear pump Progressing Cavity Pump Multistage Screw Pump Applications of Lobe Pump References External links PumpSchool.com Lobe Pump entry Short Video on the Subject of Lobe Pump Operation Pumps