For liquids, Kg / m ) at 20 c, D 7.6 k – Bronkhorst Mini CORI-FLOW User Manual
Page 32: 2 for liquids, 1000 p k, H ( kg, H o = customer customer h o
BRONKHORST CORI-TECH B.V.
4.5.2 For Liquids
Determine desired ∆p across valve.
∆
p must be at least 50% of supply pressure
Kv-value calculation
1000
p
K
m
v
⋅
∆
Φ
=
ρ
ρ
Units:
flow
-
)
/h
(kg
m
Φ
density
-
ρ
(kg / m ) at 20 C
3
and 1 atm.
delta p
- ∆p(bard)
The orifice bore diameter can be determined by:
d 7.6 K
v
=
[mm]
For C2 type of valves the diameter of the orifice can be calculated as shown above or looked up in the graph
below.
Φ
Φ
v
2
v
2
H O =
customer
customer
H O
ρ
ρ
in which:
Φ
v
= volume flow
ρ
= density
10
4
10
3
10
1
10
-1
10
1
10
0
10
4
10
3
10
2
10
1
P (bar)
d = 0.1 mm
d = 0.37 mm
d = 0.3 mm
d = 0.2 mm
d = 0.14 mm
10
2
10
0
10
-2
O
H O (ml/h)
2
10
-1
10
1
10
0
d = 1.0 mm d = 0.7 mm
d = 0.5 mm
P max.
v
If liquids have viscosity’s >15 mPa.s (water = 1 mPa.s), the flat orifice and plunger type control mechanism
cannot be used. For measuring systems only check maximum possible viscosity with factory.
page 32
9.17.050