Refuel shut-off valve closing time

[Laura24]

Hi!
I really hope that somebody can help me.
I need to find closing time for refuel shut-off vales (Any. Best of all would be for motor controled ones). Could anyone tell me how to do it or tell me where I can try to find some information.
I have a belive that it is possible to calculate but I heed your help.
Kind regards,
Laura

 

[rb1957]

that's got to depend on the valve ... ask Parker (or someone else or makes fuel systems) there might be a typical time. if you have a special app they might tailor something for you

 

[AviatorJim]

Most refuel valves I have seen are electrically controlled, but operated by fuel pressure. The only valves I have seen motor operated are crossfeed valves and shutoff valves (with a specified cycle time of less than 3 seconds), and a normal cycle time of 1 second.
..
The actual time will depend on the actual valve and application. Size of the valve, pressure and flow, power source and actuator size all are factors.
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What would happen to the aircraft if the power fails during a refuel and your valve isn't able to be energized closed? That is the main reason most aircraft have 2 refuel valves in the tank, and either can shut off the flow once the fuel level reaches the maximum depth for that tank. Even if electrical power is interupted.