Control valves
Self-acting controls
Dimensions/weights (approximate) in mm and kg
NPT / BSP
PN16
BS 10 'F'
Size
A
A1
A1
B
C
C1
KX31
KX33
KY31
KY33
DN15-1⁄2"
90
DN20-3⁄4"
DN25-1"
DN32 -11⁄4"
DN40 -11⁄2"
DN50 -2"
130
130
68
150
147
68
160
157
80
180
180
80
200
200
90
230
230
100
KX31 and KX33
DN15 - DN25
C
B
C
B
106
-
1.5
3.4
106
-
1.8
4.4
108
-
3.3
5.8
112
154
5.3
8.9
112
154
6.4
11.1
112
154
7.9
13.1
Spare parts
-
-
-
-
-
-
6.1
9.2
7.3
11.3
9.0
13.5
104
136
144
150
180
B
A
F
1
D1
E
L1
L2
H
B
U
D1
L1
F
X
A
A1
KX31 and KX33
DN32 - DN50
Valve and seat assembly
Bellows and seat assembly
Set of all gaskets
Set of bonnet studs and nuts (set of 4)
S
A
A1
KY31 and KY33
S
S
J
J
C1
G
A
A1
Kv values
DN
15
20
25
32
40
50
Kv
2.90
4.64
9.80
16.48
23.70
34.0
For conversion:
Cv (UK) = Kv x 0.963Cv
(US) = Kv x 1.156
Capacities
For saturated steam sizing capacities see TI-GCM-08.
For water valve sizing capacities see TI-GCM-09.
Safety information, installation and maintenance
For full details see the Installation and Maintenance Instructions
(IM-S21-01) supplied with the product.
Installation note:
The valve should be fitted in a horizontal line with the actuator
vertically below the pipeline.
How to order
Example: 1 off Spirax Sarco 2" KY31 self-acting control valve
having screwed BSP connections.
KX31
1⁄2" - 1"
Page 3 of 3
KX31, KX33, KY31 and KY33 Cast Iron Self-acting Control Valves
TI-P078-01 CH Issue 8
Page 3 of 3
The spare parts available are shown in solid outline. Parts drawn
in broken line are not supplied as spares.
Available spares
A1, D1, E, J, F, L1
L1, L2, E
E, L1, L2, B, U, C
Set of bonnet studs and nuts (set of 4)
S
Always order spares by using the description given in the column
headed 'Available spares' and state the size and type of valve.
Example: 1 - Valve and seat assembly for a Spirax Sarco DN40
KY33 self-acting control valve.
KX31
and
KX33
KY31
and
KY33
How to order spares
Valve and seat assembly
(DN25)
Set of all gaskets
(DN32 - DN50)
KY
11⁄4" - 2"
KX31
11⁄4" - 2"
A1
C
E
L2
Weight
A1, B, C, D1, E, L1, U
H, G, L1, B, C, U, J
B, C, U, E, G, L1, L2
4.5.34
