2 replies to this topic

[Poosticks]

I am looking to size a control valve to be capable of reducing pressure in a liquid line (water) from 20 bar down to 2 bar. Running the sizing calculations in IEC 60534 I find that the flow would choke before I could reach this pressure drop. Does this mean that it is impossible to achieve the requirement in a single valve? Or can a multi-stage valve handle this?

I do have a little difficulty with multi-stage valves in that the current standards state they are for compressible flows only (their use as anti-cavitation devices does not really address my issue).

[Bobby Strain]

Send your specifications to a reputable control valve supplier.

 

Bobby

[shvet]

I am looking to size a control valve to be capable of reducing pressure in a liquid line (water) from 20 bar down to 2 bar. Running the sizing calculations in IEC 60534 I find that the flow would choke before I could reach this pressure drop. Does this mean that it is impossible to achieve the requirement in a single valve? Or can a multi-stage valve handle this?

I do have a little difficulty with multi-stage valves in that the current standards state they are for compressible flows only (their use as anti-cavitation devices does not really address my issue).

 

Your issue is typical for BFW pumps min flow lines (spillback). There is a lot of manufacturers that can suggest you a multistage CV (usually angle type). I agree with Bobby - send your specification to a reputable vendor.