Pressure loss
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Pressure loss
Nominal flowrate
qp
Overall
length
Connection
Pressure
loss at qp
Kv-Factor
at Δp 1 bar
Graph in
diagram
m
3
/h
mm
G / DN
mbar
m
3
/h
0.6
110, 190
G
3
/
4
150
1.5
A
1.5
130, 190
G1
160
3.8
B
1.5
110
G
3
/
4
150
3.9
C
2.5
190
G1
210
5.3
D
2.5
130
G1
200
5.6
E
The indicated pressure loss of a flow sensor is at nominal flowrate qp.
With the Kv-Factor, which defines the flow rate at a pressure loss of 1 bar,
the pressure loss at any given flow rate can be calculated:
∆𝑝 = 1𝑏𝑎𝑟 × (
𝑄
𝐾
𝑣
)
2
∆𝑝 =
𝑝𝑟𝑒𝑠𝑠𝑢𝑟𝑒 𝑙𝑜𝑠𝑠 𝑖𝑛 𝑏𝑎𝑟
𝑄 =
𝑓𝑙𝑜𝑤𝑟𝑎𝑡𝑒 𝑖𝑛 𝑚³/ℎ
𝐾
𝑣
=
𝐾
𝑣
− 𝐹𝑎𝑐𝑡𝑜𝑟 𝑎𝑡 ∆𝑝 = 1 𝑏𝑎𝑟
Alternatively, the value can be taken from the diagram.
250
10
100
1000
0,1
1
10
p
re
ssu
re
d
rop
in
m
b
ar
flow rate in m³/h
21.02.2017
A
B C
D E
