User Manual

Series Series KNR/F, KNRP/F, KNR-D/F, KNRP-D/F Page 5
9520-053-en Revision 04
TM 7333 Edition 10/2008
1.4 Breakaway torques
Test medium: water 20 °C
H
igher breakaway torques may occur with other
media.
DN
p in bar
3 6 10 16 max. adm.
[mm] [Nm] [Nm] [Nm] [Nm] [Nm]
15 8 8 8 10 70
20 8 8 8 10 70
25 12 12 12 12 70
40 20 20 20 25 225
50 25 25 25 30 225
80 60 60 65 80 500
100 80 80 90 170 500
150 200 250 350 --- 2200
200/150 200 250 350 --- 2250
The breakaway torque of the actuator must be at least
just as high as the breakaway torque of the valve but
better would be 20% higher.
With highly viscous media and/or solids in the medium
it may be necessary to consider other safety
allowances in dimensioning the actuator.
This applies in particular to non-Newtonian fluids, such
as high polymer substances, suspensions, pastes,
lubricants, resins, paints etc.
Admissible safety allowances are in the range of 20-
25% of the breakaway torque.
In order to avoid damage to the valve, it is imperative
to observe the max. admissible breakaway torque!
1.5 Cavitation coefficient z for
75% duty (k
v
/k
v100
=0,75)
There are at least 3 different V-control ball/stem units
for each nominal size
DN z1 z2 z3 z4 z5 z6
15 0,65 0,60 0,60 0,60 0,58 0,43
20 0,65 0,60 0,60 0,60 0,58 0,43
25 0,65 0,60 0,60 0,60 0,58 0,43
40 0,53 0,50 0,35
50 0,47 0,39 0,32
80 0,31 0,29 0,22
100 0,27 0,24 0,16
150 0,15 0,13 0,08
200/
150
0,15 0,13 0,08
X
F
 z : non-critical conditions
X
F
 1,4 x z : tolerable cavitation
X
F
> 1,4 x z : inadmissible cavitation
1.6 Flow values Kv in %
Opening
[%]
Kv
[%]
10 5,5
20 7,6
30 10,5
40 14,5
50 20,0
60 27,6
70 38,1
80 52,5
90 72,5
100 100,0
C
haracteristics
equal percentage
Rangeability 1:25
Best control range
20-90% of angle of
opening
1.7 Flow values Kv100 in m
3
/h
There are 3-6 different V-control ball/stem units per
nominal size
DN Kv100 - Cv
[mm] [m
3
/h]
[inch] [USgpm]
15
½“
0,8
0.93
1,6
1.86
4
4.66
8
9.32
14
16.3
20
23.3
20
¾“
0,8
0.93
1,6
1.86
4
4.66
8
9.32
14
16.3
20
23.3
25
1"
0,8
0.93
1,6
1.86
4
4.66
8
9.32
14
16.3
20
23.3
40
1½“
16
18.64
25
29.12
40
46.6
50
2"
16
18.64
25
29.12
40
46.6
60
69.9
80
3"
40
46.6
80
93.2
120
139.8
160
186.4
100
4"
60
69.9
100
116.5
160
186.4
250
291.25
150
6"
160
186.4
250
291.25
400
466
200/
150
8/6"
160
186.4
250
291.25
400
466
X
F
= Differential pressure ratio
p = Differential pressure input/outlet
p
1
= Absolute pressure at inlet
p
v
= Vapour pressure at operating temp.
X
F
p
pp
v
=


1