Abstract: The flow controlling valve, particularly mounted in a pipe flange structure, comprises a cylindrical housing, a flow passage whose cross section is controllable, a valve seat, and a valve member and at least one auxiliary valve mounted in the housing. The valve seat is formed as a mushroom member whose mushroom head has an edge with an adjacent seating surface and whose stem is connected to at least one supporting cross piece extending across the flow passage. The valve member is a spring-loaded hollow piston guided in the housing whose interior space forms the flow passage which is mounted with its inner edge positionable on the seating surface of the mushroom head. The auxiliary valve has a spring-loaded auxiliary stopper member with an associated auxiliary valve seat which controls a flowing medium branching from the main flow by a metering element.