Displacement machine, in which two or three screw spindles engage one another such that the edges seal against one another and against the housing. In displacement areas between the housing and the spindles, the oil is pushed towards the pressure connection with almost no pulsation. This means that screw spindle pumps are very quiet. However, no volume adjustment is possible. The pressure range is largely under 60 bar at an output volume of up to a few thousand lpm. However, screw spindle pumps for up to 200 bar are also built in the case of small output volumes (e.g. for lifts).
Screw spindle pump