These PV DBS Series Feed Water Heater Isolation Systems valves are designed to bypass high pressure feed water around a group of heaters in the event of high water level in the shell caused by a defective tube, weld or drain system. The time available to give protection to a turbine in modern feed systems is short but these valves can operate in approximately 5 seconds in a 300mm bore pipe system with the minimum of hydraulic shock.

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