valve throttling

[nomad111]

I have a butterfly valve in a recirc line throttled back,on the Discharge side, on that valve it is tagged to keep closed 5 "clicks", what purpose would this serve? Water is the element for a scrubber system.

 

[JLSeagull]

A wild guess is that the pump curve is not well suited to the piping system. Perhaps the valve attempts to make a bad pump selection workable.

 

[Golestan]

It might be to create a DP in the flow path.