
PRESSURE DROP GRAPH
RELATIVE FLOW
COEFFICIENT
The relative flow coefficient is the flow
rate through the valve as a function of
the degree of valve opening.
X axis: Opening percentage of the ball
Y axis: Relative flow coefficient
K
V
100 FLOW
COEFFICIENT
The K
v
100 flow coefficient is the Q flow
of litres per minute of water at a
temperature of 20°C that will generate
∆
p= 1 bar pressure drop at a certain
valve position.
The K
v
100 values shown in the table are
calculated with the valve completely
open.
DN
10
15
20
25
32
40
50
Kv100 l/min
83
88
135
256
478
592
1068
195