A valve for switching over liquid paths, particularly for pressure
exchanger installations with tubular pressure exchanger chambers (3)
through which an alternating flow occurs, in which a rotatable control
element (10, 10.1) having a plurality of flow paths is mounted in a
housing (11), which in turn comprises a plurality of connection opening
(12, 16, 17, 46) connected to a first pipe system and to an end of at
least one pressure exchanger. Another end of the pressure exchanger is
connected to a second pipe system through a valve. A motorized drive
shaft (50) rotates the control element so as to alternately connect the
control element flow paths to openings inside housing (11). Oncoming flow
to the control element may come from an axial direction or from a radial
direction, and outgoing flow from the control element occurs in the axial
direction.