10
1 T 70 en
❑
Place the locking tools in position and tighten as
shown in Fig. 19. Remove the extractor tool.
❑
Lower the ball with bearings and seats into the
body, in the 'Open position'. Check that the back
face of the seat does not damage the support
ring seat when lowering the ball into the ball
body. See Fig. 20.
❑
Remove the locking tools.
❑
Install the bonnet gasket. This graphite gasket
should always be replaced.
❑
Place the bonnet in position. If the gland pack-
ings are in place and in good condition, lower
the bonnet carefully, ensuring that the shaft key
groove does not damage them. If necessary
replace the gland packings as explained in
2.6.12.
❑
Tighten the bonnet nuts by using the torques
given in Table 2. Tighten in the order shown in
Fig. 22.
❑
Assemble the gland packing as described in 4.2.
5
TESTING THE VALVE
The hydraulic body test shall be carried out after the
reassembly.
Test pressure shall be in accordance with an applica-
ble standard. Use the pressure required by the pres-
sure class or the flange bore. Keep the valve in the half
open position during the test.
If the tightness of the closure member is also to be
tested, please contact the manufacturer.
Fig. 20
Lowering the ball into the body
Fig. 21
Bonnet gasket
Table
2
Recommended tightening torques of the
body stud nuts (for information only)
Recommended tightening torques
Thread
Torque, Nm
Torque, lbf.ft.
5/16 UNC 24
18
3/8 UNC
45
35
1/2 UNC
100
75
5/8 UNC
200
150
3/4 UNC
350
250
7/8 UNC
500
350
1 UNC
700
500
1 1/4 8UN
1300
950
1 1/2 8UN
1600
1200
1 3/4 8UN
1600
1200
2 8UN
2500
1800
2 1/4 8UN
3500
2600
2 1/2 8UN
5000
3700
2 3/4 8UN
6300
4600
3 8UN
8400
6200
Note: Threads must be well lubricated
Fig. 22
Nut tightening order
CAUTION:
Pressure testing should be carried out using equip-
ment conforming to the correct pressure class!
