SFD accident with pressure shut-off device a segmented overview SFD accident with pressure shut-off device segment of accidents with pressure valve and shut-off valve integrated in one segment, for hydropower turbine generator set speed control system to prevent the unit too fast and water hammer, provide safe and reliable protection for the normal operation of the hydro group. By optimizing the design of this product, all components are plug connection plate, high degree of integration, good sealing performance, installation, commissioning, easy maintenance, small size, reliable action. Second, the technical parameters Rated pressure: 2.5MPa 4.0MPa 6.4MPa Power supply voltage: 220VDC 110VDC 24VDC 220VAC output contacts: SPDT Contact capacity: 5A / AC220V Ambient temperature: 5 ~ 40 ℃ Relative humidity: ≤95% RH Installation: horizontal, vertical installation can be connected: flange connection, flange standard: GB9119-2000