Dry Compressing Screw Vacuum Pumps

Dry screw vacuum pumps provide a constant pumping speed over a large pressure range and low ultimate pressures, but with high technical effort.
For example, they are well suited for continuous distillation processes in which a low pumping speed is required or as a backing pump for Roots pumps. Screw pumps are of limited use in processes with solids and/or vapors prone to sublimation.
Dry screw vacuum pumps belong to the group of positive displacement pumps. Two parallel screw rotors, which are synchronized by means of a gearbox, turn against each other in the pump housing. The gas to be pumped is enclosed in the interior of the pump and compressed in the direction of the outlet by the turning movement of the screws.