In nearly every food manufacturing company raw materials, semi-finished products and
end
products are conveyed using pumps. Pumps are also being used for dosing.
Positive displacement means that a portion of fluid is sucked in and discharged. A
pulsating
flow is also possible.
Lobe pump: Per rotation a certain volume is being pumped. The pressure is relatively
low.
Applicable both for low and high viscous fluids, even when these contain solid particles.
Membrane pump: A membrane is moving to the lowest point creating low pressure and
through
inlet valves fluid enters the cylinder.
When the membrane reaches the highest point, the fluid is pumped through outlet valves.
This
causes the outlet flow to pulsate. The membrane can be driven by motor, by air or by oil.
This pump type functions hygienically, it has no problems when running dry and it can
be used
to dose. The quality of the membrane determines the durability of the pump.