Masoneilan 41005 Series Globe Valve Instruction Manual | 15
© 2015 General Electric Company. All rights reserved.
Grease the threads of the valve body studs (21) and the
bearing surfaces of the body stud nuts (8).
Screw on the body stud nuts by hand. Tighten the nuts
lightly and evenly so that the internal parts are held in
place. The face of the bonnet should be parallel to the
upper face of the body.
Slide the guide bushing (22) onto the valve plug stem and
let it drop to the bottom of the packing box housing.
6.6 Tightening of Body Stud Nuts
Alignment of internal parts
In order to achieve perfect alignment of the seat ring and
the valve plug, a force must be applied to the plug stem
during tightening of the bonnet which results in correct
relative positioning of the two parts.
The force can be applied with the pneumatic actuator
as follows:
Place the actuator on the valve bonnet (7) by means of
the yoke nut (33) or attachment screws and connect the
valve plug stem to the actuator stem. See chapter on
actuators for installation instructions.
During this operation, make sure that the plug does not
turn when it is seated. If the plug travel is very small and
there is a large amount of plug stem inside the actuator,
it may be necessary to remove the yoke nut and lift the
actuator so that the plug is not touching the seat.
Align the internal parts as follows:
In the case of air-to-extend actuators, supply air to the
actuator at the maximum pressure indicated on the
serial plate and in the case of spring-to-extend actuators,
do not supply air to the actuator, so that the optimum
positioning of the valve plug and seat can be obtained.
Single bolting circle:
Evenly tighten the nuts (8) by applying the torque
indicated in table in Figure 10 and the tightening
sequence in Figure 11.
Double bolting circle:
Beginning by the internal nuts, manually screw all the
bolts. Screw the internal nuts in order indicated by the
Figure 2 and screw them by successive, uniform and
progressive levels. During the tightening, make sure
that the bonnet face stays parallel at that of the body.
When the torque values given in the following table are
reached, the bonnet face must be in contact with that
of the body. Screw the external nuts in order indicated
by the Figure 2 and screw them by successive, uniform
and progressive levels until the torque values given in the
following table.
Torque Valve body stud/Bonnet
Body
Nuts (21)
Torque
Nominal
size (in)
ASME
Pressure
classe
Size (in)
No.
m.N
ft.lb
2
3 x 2
4 x 2
300/600
3/4 – 10
6
150
110
2
900/1500
7/8 – 9
8
250
180
2500
1 1/4 – 8
6
550
410
3 x 2
4 x 2
900/1500
1 – 8
8
400
300
3
4 x 3
6 x 2
300/600
3/4 – 10
8
150
110
900 /
1500
900/1500
1 1/4 – 8
6
800
600
3
2500
1 1/2 – 8
6
1050
775
4
6 x 4
8 x 4
300/600
7/8 – 9
8
250
180
900
1 1/2 – 8
6
1200
900
1500
1 1/2 – 8
6
1400
1000
4
2500
1 5/8 – 8
8
1250
930
6
8 x 6
10 x 6
300
1 – 8
8
400
300
600
1 – 8
12
350
250
900/1500 1 3/4 – 8
8
1800
1300
6
2500
1 7/8 – 8
8
1900
1400
8
10 x 8
12 x 8
300/600 1 1/4 – 8
8
700
500
900
1 3/4 – 8
8
1900
1400
1500
1 3/4 – 8
8
2300
1700
8
2500
1 3/4 – 8
12
1650
1220
10
300
1 1/2 – 8
8
1200
900
600
1 1/2 – 8
12
1200
900
900
1 3/4 – 8
12
1800
1300
1500
1 3/4 – 8
12
2000
1500
2500
2 – 8
12
2800
2070
12
16 x 12
300
1 1/2 – 8
8
1300
950
600
1 1/2 – 8
12
1200
900
900
1 1/2 – 8
16
1200
900
1500
1 3/4 – 8
16
2000
1500
12
2500
1 7/8 – 8
20
2200
1630
16
300
1 1/2 – 8
12
1300
950
600
1 1/2 – 8
16
1300
950
900
1 1/2 – 8
20
1400
1000
1500
1 3/4 – 8
20
2300
1700
2500
2 – 8
24
2650
1960
20
300
1 3/8 – 8
24
900
650
600
1 3/4 – 8
24
2000
1500
900
1 7/8 – 8
24
2700
2000
24
300
1 3/4 – 8
20
1900
1400
600
1 3/4 – 8
26
2200
1600
30
300
1 3/4 – 8
28
2000
1500
Figure 10
