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
mbar
m
3
/h
0,6
110
G
3
/
4
75
2.2
A
1,5
110, 130
G
¾
, G1
135
4.1
B
2,5
130
G1
135
6.8
C
The indicated pressure loss of a flow sensor is at the nominal flowrate qp.
Using 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
250
10
100
1000
0,1
1
10
p
re
ssu
re
los
s
in
m
b
ar
flow rate in m³/h
21.02.2017
A B C
