Ames Fire & Waterworks Diaphragm Control Valves Series 900GD / 900AD

Models 900GD (Globe) and 900AD (Angle) are Ductile Iron, full port, dual chamber basic valves that incorporate a one-piece disc and diaphragm assembly. When pressure is applied to the upper diaphragm chamber and released from the lower diaphragm chamber, the valve travels to a closed position. When pressure is applied to the lower diaphragm chamber and released from the upper diaphragm chamber the valve travels to a full open position. When pressure is balanced between the upper and lower diaphragm chambers, the valve will hold an intermediate position until commanded to modulate open or closed by the pilot control system.