Series 6700 High Pressure Modulating
Automatic Recirculation Valve

The 6700 valve is used for high pressure differentials on the bypass line and modulating applications. Pressure envelope up tp Class 2500 and differentials up to 300 barg. All valves are precision set to high tolerances for the most demanding of applications. The Blackhall Automatic Recirculation Valve - SERIES 6700 is a fully automatic valve designed for use on the discharge side of centrifugal pumps. The principle function of the valve is to ensure the flow of fluid or gas through the centrifugal pump does not fall below a set value (i.e. 'minimum flow valve') at any time during either pump start up, pump shut down or when the main-flow is throttled to less than the pump minimum flow. The Blackhall Automatic Recirculation Valve - SERIES 6700 combines four functions in one:

a) Flow sensing
b) By-Pass Control Valve
c) Labyrinth Spool for pressure reduction
d) Main line Non Return Valve