Low pressure check valve on a TANK 1

[Giuliano81]

My process engineer requested a low pressure check valve with a differential pressure of 0 kg/cm2 (perhaps, near the zero) on a line that goes from a tank to a wet flare header. The question is: a check valve with Dp=0 kg/cm2 is always closed or open i suppose, so what is its real use?

Regard
Giuliano

 

[ione]

You need to have a differential pressure to open the check valve. Anyhow There are available check valves that ask for low differential pressure to work (i.e. disk check valve with no spring).
To go further into this matter take a look to this thread

http://www.eng-tips.com/viewthread.cfm?qid=253668&page=2

 

[Giuliano81]

Thanks

Giuliano

 

[Compositepro]

Look for "conservation vent".