A screw spindle pump constituted by at least two parts is disclosed. The first part includes a housing and at least one spindle system disposed in the housing and capable of being driven in a rotational manner. Furthermore, a pressure region disposed downstream of the spindle system and at least one outlet opening which is connected to the pressure region, the outlet opening discharging the delivery medium out of the pressure region. The second part includes at least one low-pressure chamber disposed upstream of the spindle system and at least one inlet opening for the delivery medium into the low-pressure chamber. The first part and the second part are coupled together, preferably in a rotational manner, so that they can assume at least two different relative positions.