Flowserve SB Control Valves - Manual (Page 6)

ShearStream SB FCD VLENIM4152-01 07.09
6
5. Remove the compression spring (10) in the
same way.
6. Carefully wash all parts with warm water and
then, if necessary, with a suitable solvent. Never
scrape the sealing surfaces with hard tools.
7. Examine the surface of the ball sector (2).
Remove any deposits and clean the ball sector
as described in item 6 above.
N.B. Take care not to scratch the sealing
surface of the ball sector.
8. Inspect the seat ring (11) and clean it as
described in item 6 above.
9. Inspect the sealing ring (12) - it need not be
removed from its groove in the body. Fit a new
sealing ring if the original one is damaged.
10. Lubricate the ball segment with a suitable
lubricant, such as Molykote Paste U, Gleitmo
700 or similar.
11. Lubricate the surface of the sealing ring (12)
with a silicone-base grease, such as Silicone
grease DC 111, Silicone grease TKM 1011 or
similar.
12. Fit the compression spring (10) and seat ring (11).
Turn the ball sector (2) until it is in contact with
seat ring (11). Use a soft object to press the
seat ring towards the compression spring (10)
to enable the ball sector to move into its proper
position. Continue turning the sector to the
closed position.
13. Fit the indicating pin (23).
N.B. An additional function of the indicating
pin is to restrict the travel of the ball segment
to 95 - 100°, so that it will always remain in
contact with the seat ring.
9.3 To inspect and replace the upper shaft seal of
Safeguard type
The stuffi ng box usually requires inspection and adjust-
ment after the valve has been taken into service.
After a certain period of time in service, it may some-
times also be necessary to replace the packing.
Make sure that the valve is not under pressure.
1. If an actuator is fi tted to the valve, remove it.
Begin by removing the valve positioner. This
can easily be done after the plastic cover of the
valve positioner has been removed. Remove the
four bolts securing the valve positioner to the
actuator. Then remove the nuts securing the
actuator to the valve mounting plate and dismantle
the actuator.
2. Remove the key.
3. Remove the nuts (18). Remove the gland (5).
Then remove the packing (19).
pin is to restrict the travel of the ball segment
to 95 - 100°, so that it will always remain in
contact with the seat ring.
4. Clean the surfaces of the stem, gland (5) and
packing area in the valve body.
5. Carefully examine the surface of the stem which
must be completely free from marks and
scratches.
6. Grease the stem with a suitable grease, such as
Silicone grease.
7. Mount new packing (19). Then mount the gland
(5) and the nuts (18).
8. Tighten the nuts (18) suffi ciently to ensure that
the packing is correctly seated.
Note: Check the tightness of the packing after the
valve has been taken into service, retighten the
nuts (18), if necessary.
9.4 To inspect and replace the upper shaft seal of
Zebra CL™ type
The stuffi ng box usually requires inspection and adjust-
ment after the valve has been taken into service.
After a certain period of time in service, it may some-
times also be necessary to replace the packing.
1. Remove the actuator as described in section 9.3,
tems 1. Remove the keys (22) and the indicator
pin (23).
2. Remove the nuts (18), spring cups and gland (5).
Then remove the packing (19).
3. Clean the surfaces of the stem, gland (5) and
packing area in the valve body.
4. Carefully examine the surface of the stem which
must be completely free from marks and
scratches.
5. Grease the stem with a suitable grease, such as
Silicone grease.
6. Mount new packing (19) when mounting the
gland (5) and the spring cups and then the
nuts (18).
7. Tighten the nuts (18) suffi ciently according to the
torque table in catalogue sheet FCD NFEETB4152-01
to ensure that the packing is correctly seated.
Note: Check the tightness of the packing after the
valve has been taken into service.
9.5 To change the gasket at the lower stem
1. The gasket (7) should be replaced in conjunction
with the inspection of the seat ring (11).
2. Remove the bolts (20) and the cover (6).
3. Withdraw the stem (4) and remove the gasket (7).
4. Carefully clean the inside of the cover (6) and the
stem (4).
5. Fit a new gasket (7) and lubricate the small end
of the stem with a suitable lubricant, such as
Molykote Paste U or Gleitmo 700.
6. Fit the stem (4) with the gasket (7).
7. Spray the bolt threads with locking compound,
such as Loctite 641.
8. Fit the cover (6) and tighten the bolts (20).