Bronkhorst FLOW-SMS Series - Manual (Page 22)

BRONKHORST HIGH-TECH B.V.
9.17.057 page 22
4.1.5 Maximum pressure drop
For solenoid operated control valves with small orifices the maximum allowable pressure drop for gases is according
to the general table below. Please keep in mind that the pressure rating for FLOW‐SMS is 10 bar only. The Kv value of
the shut‐off valves, in front of and behind the flow/pressure controllers, must be 1.5 times larger than total Kv value
of the controllers. Otherwise the pressure drop over the shut‐off valve will disturb the control performance.
Diameter [mm] K
v
Normally closed
p max. [bard] Normally opened
p max. [bard]
0,05
0,07
0,10
0,14
0,20
0,30
0,37
0,50
0,70
1,00
1,30
1,50
1,70
2,00 4,33 x 10
‐5
8,48 x 10 ‐5
1,73 x 10
‐4
3,39 x 10 ‐4
6,93 x 10
‐4
1,56 x 10
‐3
2,37 x 10 ‐3
4,33 x 10
‐3
8,48 x 10
‐3
1,73 x 10 ‐2
2,93 x 10
‐2
3,90 x 10 ‐2
5,00 x 10
‐2
6,63 x 10
‐2
40
30
30
30
30
30
30
30
24
12
8
6
5
3,6 30
20
20
20
20
20
20
20
15
8
5
n.a.
n.a.
n.a.