Tightening Of Body Stud Nuts - GE Masoneilan 41005 Series Instruction Manual

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
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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
ASME
Nominal
Pressure Size (in)
size (in)
classe
2
3 x 2 300/600 3/4 – 10
4 x 2
900/1500 7/8 – 9
2
2500 1 1/4 – 8
3 x 2
900/1500 1 – 8
4 x 2
300/600 3/4 – 10
3
900 /
4 x 3
1500 1 1/4 – 8
6 x 2
900/1500
3 2500 1 1/2 – 8
300/600 7/8 – 9
4
6 x 4 900 1 1/2 – 8
8 x 4
1500 1 1/2 – 8
4 2500 1 5/8 – 8
6 300 1 – 8
8 x 6 600 1 – 8
10 x 6 900/1500 1 3/4 – 8
6 2500 1 7/8 – 8
300/600 1 1/4 – 8
8
10 x 8 900 1 3/4 – 8
12 x 8
1500 1 3/4 – 8
8 2500 1 3/4 – 8
300 1 1/2 – 8
600 1 1/2 – 8
10 900 1 3/4 – 8
1500 1 3/4 – 8
2500 2 – 8
300 1 1/2 – 8
12 600 1 1/2 – 8
16 x 12
900 1 1/2 – 8
1500 1 3/4 – 8
12 2500 1 7/8 – 8
300 1 1/2 – 8
600 1 1/2 – 8
16 900 1 1/2 – 8
1500 1 3/4 – 8
2500 2 – 8
300 1 3/8 – 8
20 600 1 3/4 – 8
900 1 7/8 – 8
300 1 3/4 – 8
24
600 1 3/4 – 8
30 300 1 3/4 – 8
Figure 10
Masoneilan 41005 Series Globe Valve Instruction Manual | 15
Nuts (21) Torque
No. m.N
6 150
8 250
6 550
8 400
8 150
6 800
6 1050
8 250
6 1200
6 1400
8 1250
8 400
12 350
8 1800
8 1900
8 700
8 1900
8 2300
12 1650
8 1200
12 1200
12 1800
12 2000
12 2800
8 1300
12 1200
16 1200
16 2000
20 2200
12 1300
16 1300
20 1400
20 2300
24 2650
24 900
24 2000
24 2700
20 1900
26 2200
28 2000
ft.lb
110
180
410
300
110
600
775
180
900
1000
930
300
250
1300
1400
500
1400
1700
1220
900
900
1300
1500
2070
950
900
900
1500
1630
950
950
1000
1700
1960
650
1500
2000
1400
1600
1500