2 replies to this topic

[krishnamurthy]

If a line has a control valve and assume that it has different flowrates, say for eg 100 kg/hr, 150 kg/hr, and 200 kg/hr, can anyone  tell me in which flow rate the delta P is higher?  Kindly help. 

 

[latexman]

What delta P are you asking about? The delta P of the entire system, line + control valve, or just the control valve or just the line? Be more specific please.

[Pilesar]

Pressure differential across the valve is the highest when the valve is closed when there is no pressure drop in the piping due to friction. As flow increases, there is more pressure drop in the piping to and from the valve so the pressure drop across the valve decreases. With the valve wide open, the pressure drop is lowest across the valve.