Valve Capacity

Please select media

Flow Coefficient - Cv - for Liquids (Metric)

Cv = 11.6 q (SG / ΔP)1/2         (1b)

where

q = water flow (m3/h)

SG = specific gravity (1 for water)

ΔP = pressure drop (kPa)

For liquids the flow coefficient - Cv - expresses the flow capacity in gallons per minute (GPM) of 60oF water with a pressure drop of 1 psi (lb/in2).

STEP 1 : Select Unit
  IMPERIAL METRIC
 
STEP 2 : Select Liquid
 
 
STEP 3 : Enter Specific Gravity (if User Defined)
  Specific Gravity
 
STEP 4 : Add flow rate and pressure drop
  Flow Rate
 m3/hUS gal per minute
  Pressure Differential (ΔP) kPa psig
  Flow Coefficient Kv Cv =
 

Flow Coefficient - Cv - for Air and other Gases

Cv = q [SG (T + 460)]1/2/ [1360 (dp po)1/2]

where

dp = (pi - po)

po = outlet gas absolute pressure (psia)
 
STEP 1 : Select Unit
  IMPERIAL
 
STEP 2 : Select Gas
 
 
STEP 3 : Enter Gas Temperature, Inlet Pressure, Outlet Pressure and Specific Gravity
  For proper mass flow conversion (Kg/HR to m3/HR), enter Specific Gravity at standard atmospheric conditions (20oC / 70oF)
  Temperature   oCoF
  Inlet Pressure BARpsia
  Outlet Pressure
(must be > 0)		 BARpsia
  Specific Gravity
 
STEP 4 : Add flow rate
  Flow Rate
 m3/h (Cu. ft./m) (f.a.d)
  Flow Coefficient Kv Cv =