Fire Hydrant Valve By K.b.j. Engineering Services

Fire Hydrant Valves are designed to perform one or other of these services. the construction is that of an outlet chamber with vulcantile ball, and discharge orifice of appropriate type for the duty in question. Double acting air valves combine both functions, having two chambers, vulcantile balls, and separate outlets. Ball hydrants, where still used, are often made to serve as air valves for handling bulk volumes, with single air valve fitted in the vicinity to take care of small underpressure accumulations. Otherwise double air valves are usually installed.
Single Small Orifice
Automatically discharges accumulated air during normal pipeline flow. Normally the valve is sealed by the up-thrust of a submerged rubber ball. Any build up accumulated air in the valve chamber will depress the water level sufficiently, causing the ball to drop away from the orifice seat and allowing the air to escape.
Single Large Orifice
Automatically exhausts air when filling or allows the admission of air during emptying of a pipeline.