In this session we are gonna discuss about Normally Open, Anti Surge, pilot-operated and diaphragm-actuated control valve. This Anti-Surge Pump Start Control Valve has a double chamber actuator for positive and reliable performance with an external lifting spring, which gives the valve its normal opening characteristic. This allows the control valve a zero reaction time, anticipating and dissipating any overload of pressure or excess air at the start of the pump. Once the surge has passed and the system piping pressure has normalized, the overvoltage pump valve will close and continue to operate as a relief valve, relieving pressure peaks when necessary, maintaining system pressure at your designated level. The start control valve of the anti-starter pump is a self-contained valve that operates only with line pressure that does not require an external power source.
Standby: The Valve is a Normally Open valve with an external lifting spring  keeping the valve in a fully open position as default when the system piping is depressurized, as might be before a pump start-up. When the pump starts the initial pressure surge and excess air will be expelled from the system through the valve.
Relief / Modulating: After the surge has passed, air has been exhausted and the system piping reaches normal
pressure, the valve will continue duty as a pressure relief / sustaining valve, controlled by the pressure
relief pilot valve  which should be pre-adjusted to the required pressure. When the system pressure is above the
set pressure, the pilot valve will open, enabling water to exit the main valve control chamber  allowing the main
valve to open and relieve system over-pressure.
Closed: When the system pressure falls below the set pressure the pilot valve will close allowing inlet pressure to
accumulate in the main valve control chamber, closing the main valve. The closing speed can be set by changing the
needle valve  adjustment. The valve will remain closed and will open only when either the piping system pressure exceeds the required set pressure or when there is no pressure in the piping system.
- Pump start-up dump valve
- Vertical fire pump air release
- Pressure sustaining/Relief
- Pump protection from discharge overpressure