Steam Valve Cv Calculator
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for use with Tridium Niagara, Vykon, Staefa Talon, Distech EC-Net, Johnson Controls Facility Explorer FX FX-40,
Honeywell WEBsAX, Invensys Niagara Framework systems and many others.
Emptor: While we believe
the calculations to be accurate,
the user bears the ultimate responsibility for proper valve sizing.
Use good engineering practices and check, check, check.
Calculate Flow, Pressure Drop, and
Click on the button you want to calculate, after filling
in the other parameters.
The critical pressure drop is 45% of the absolute inlet pressure.
= (Inlet gauge pressure + 14.7 PSI) x 0.45.
Increasing the pressure drop beyond critical does not result
in more steam flow.
For steam inlet pressures of 12 PSIG or less, choose a pressure
drop up to the inlet pressure.
80% of inlet gage pressure is recommended, and used in the "Find
Best Drop" calculations.
For steam inlet pressures greater than approximately 12 PSIG,
choose a pressure drop less than or equal to the critical pressure
Note: After entering the steam line pressure, the "Find
Best Drop" button chooses the higher of (80% of inlet pressure)
or critical pressure drop.
If your calculated Cv does not exactly match what
you have available, choose the valve with the next greater Cv.
E-mail us ! Let us know if you find this useful, and also
if you have any comments for improvements.
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The "best" pressure drop results in the best valve
controllability. You can enter your own pressure drop value if
your requirements are different.