Design

The screwpump is using static compression as design principle. The screw vacuumpump consists of two screws. One of it with righthand thread and the other with a left hand threat. Both screws turn in the compression housing without frction, with very tight clearances. They are synchronizedvia a precision gear. The compression housing and the special shape of the screws form the compression chambers. Due to the opposite rotation of both screws the chamber connected with the suction port is enlarged and the gas is being sucked into the compression chamber. There is no lubrication required in the compüression chamber. The screws are made of ductil iron. The chamber moves axially from the suction to the discharge side. The mass of the gas is increasing due to the backflow from the discharge. At the discharge side, the chamber is moved against the axial housing wall and the volume is reduced until the front surface of the screw opens the pressure channel and the pre-compressed gas is discharged through the pressure duct to atmosphere. Cooling is achieved by means of a double wall waterjacket of the housing. The sealing is designed by means of two glidering seals at the driveside and a ptfe lipseal at the nondrive side. The bearing at the drive side is fixed with a twin ballbearing. At the non drive side the screw expands and the bearing is designed with rollerbearings.