en2015-08-18 17:38 PM CESThttp://inspire.ec.europa.eu/codelist/WaterAppurtenanceTypeValue/systemValve:1http://inspire.ec.europa.eu/codelist/WaterAppurtenanceTypeValue/systemValveSystem valve.A system valve is a facility that is fitted to a pipeline or orifice in which the closure member is either rotated or moved transversely or longitudinally in the waterway so as to control or stop the flow. System valves are used to regulate pressure, isolate, throttle flow, prevent backflow, and relieve pressure. NOTE System valve types include Gate, Plug, Ball, Cone, and Butterfly. These specific types may be classified as isolation valves.