Patent attributes
A differential dry pipe control valve for fire protection sprinkler systems includes an eccentric plug that rotates and separates supply water and system air pressure and uses an integral actuator that maintains the seal of the eccentric plug with a smaller ratio of air pressure to a higher supply water pressure. When the sprinkler system is actuated, the actuator allows the rotary eccentric plug to open the waterway and includes an eccentric plug opening that swings out of the waterway to reduce friction loss of the water supply. The eccentric plug includes a conical rubber coated seat surface and dynamic metal seal seat that seals due to water pressure eliminating close tolerance mating of sealing components. The actuator includes an integral alarm connection to provide a required alarm function and acts as a pilot differential actuator to provide the required operation of an approximately 5.5:1 ratio differential dry pipe control valve. This valve can also function as an open system Deluge valve or closed system Preaction valve for sprinkler systems that operate from separate detection systems where the supply liquid holds the valve closed until a detection system detects a fire and signals the deluge valve to open for discharge of suppressant liquid on the protected fire area.
