What happens to the interlocked shut-off valve when the purge air stops?
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Are cut-off valves also divided into open and closed types?
The shut-off valves in critical areas are equipped with their own independent air tanks, which allow for some time to be gained; even when the air supply is cut off, pressure is not lost immediately, as the buffer tanks at the inlet of the system still provide a period of time for operation~~~
Of course, there is a switch to turn the wind on and off. Lift the cylinder and turn the valve core 90 degrees, and it changes.
It depends on the operating principle of your shut-off valve
According to process requirements, cut-off valves can operate in an open state when air is lost or in a closed state when air is lost. So there will be changes.
Consider wind pressure, switch speed, and valve selection; sometimes it’s necessary to make distinctions, while other times it isn’t
It can be separated; what will happen when the air purification is stopped? Depending on the characteristics of the valves, the air flow will either be turned on or off
Check the nameplate: FC, FO, FLO, FLC
When the purification air supply to the device is stopped, the FC valve closes; when air flow is enabled, it opens. In case of a fault, it closes. The FO valve closes when air flow is stopped, and it opens in case of a fault, with the valve fully open. FC/FL: Wind open/hold position; instrument air is stopped, and the valve remains at the opening degree it had just before that, until the hold-position valve fails for various reasons, after which the valve closes. FO/FL: Wind closed/hold position; the opposite of the above.
In practical applications, when the instrument air is interrupted, even in the absence of a gas storage tank, the pressure in the pipeline network does not drop to 0 immediately. Therefore, unless an interlock is triggered, the valves will remain in a state of uncertain opening degree for some time.