Neles XG Series, Инструкция по установке, обслуживанию и эксплуатации

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1X72EN - 9/2020 7
must be tightened with care because excess force may damage the
V-rings.
•
Make sure that the valve is not pressurized.
• Detach the actuator and bracket according to the instructions in
Section 4.4.
• Remove the key (10).
• Remove the nuts (18), the disc spring sets (150) and the gland
(9).
• Remove old packing rings (69). Do not damage the surfaces of the
packing ring counterbore and shaft.
• Clean the packing ring counterbore.
• Place the new packing rings (69) over the shaft (5). The gland fol-
lower may be used for pushing the rings into the counterbore. Do
not damage packing rings in the shaft keyway. See Fig. 11 for
proper orientation.
• Pre-compress the packing rings first either by tightening the
gland nuts (with or without disc springs) to the torque Tt or by
tightening the gland with disc springs to the height H
2
. See Fig.
11 and the value from Table 1.
• Carry out 3…5 operation cycles with the valve. Suitable range of
movement is about 80 %.
It is not necessary to fully close or open the valve during the
operation.
• Loosen the gland nuts. Place the disc spring sets (150) on the
gland studs as applicable. Retighten the nuts (18) to the torque T
t
or so that the disc springs are compressed to the height H
2
, see
Table 1.
• If the leakage still occurs when the valve is pressurized, re-
tighten the nuts but don't exceed the value in the Table 1 by 50 %
or do not fully compress the disc springs.
Table 1 Tightening of gland packing
Fig. 11 Gland packing
150
66 8
69
9 18
10
14
A
H
1 H
2
Valve size Shaft dia Spring dimensions (free)
PTFE V-ring Graphite Graphite (Braided)
Disc spring Nut Disc spring Nut Disc spring Nut
DN NPS mm A, mm H1, mm H2, mm Tt, Nm H2, mm Tt, Nm H2, mm Tt, Nm
50 02 20 20 22 21.0 3 20.2 6 - -
80 03 20 20 22 21.0 3 20.2 6 - -
100 04 30 25 30.5 29.3 8 28.4 14 - -
150 06 40 25 30.5 28.9 10 28.2 15 - -
200 08 40 25 30.5 28.9 10 28.2 15 - -
250 10 55 35.5 41 38.8 23 37.4 38 - -
300 12 55 35.5 41 38.8 23 37.4 38 - -
350 14 75 50 59 57.3 43 55.3 91 - -
400 16 85 50 59 57.1 48 54.9 102 - -
450 18 85 50 59 57.5 54 56 108 54.5 162
500 20 85 50 59 57.5 54 56 108 54.5 162
500 20 95 71 73 70.8 126 68.6 252 66.4 378
600 24 95 71 73 70.8 126 68.6 252 66.4 378
600 24 120 71 73 70.8 156 66 311 63.6 467