Exhaust Booster in Control Valve Actuators

[Papps]

Looking for a option to quickly open the Recycle Valve of a Compressor during it's fail safe mode (Fail to Open).

Came across placing of a Exhaust Booster in the actuator of a control valve will make the valve to open quicker.

What is the difference between flow booster and exhaust booster and will the installation of exhaust booster will function only during it's fail safe mode or even in it's normal operating mode?

 

[georgeverghese]

Yes, an exhaust relay or booster should help to decrease time to full open for a FO compressor recycle valve.

A volume booster is used to increase the volume of the signal air to an FC actuated valve to enable the valve to reach the desired position quicker. It doesnt change the signal pressure, it increase signal volume flow. In some bigger valves, it is also important to check that the instrument air supply tubing to these valves is not bottlenecked (I've been tripped up on this once).

 

[Papps]

Can I understand line, Application of Exhaust Booster is in FO valves and Application of Flow booster is in FC valves.

Exhaust Booster helps to open the valve the quicker and Flow booster helps to close the valve quicker.

Please correct me if I am wrong for my better understanding.

 

[LittleInch]

Not necessarily as it depends on the action of the actuator (mainly FC valves need air to be released), whether it has spring providing the motive force or whether this is a FIP double acting actuator.

Exhaust booster is simply another parallel larger air release valve to allow the valve to move quicker when using a spring to move it.

A flow booster does the opposite by providing a larger flow or air to move the actuator or change the air driven pilot valve.

You need to look at the actuator spec and diagram to see what it does in your case.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[georgeverghese]

Exhaust boosters can also be used in FC valves to increase the speed of closing- one common application is the throttle valve on an expander feed.
Flow boosters are typically used in FC valves to increase speed of opening.

These devices are usually located on the signal output tubing from the control valve positioner leading up to the control valve actuator.

 

[Papps]

Thanks for your replies guys....