Flowserve NAF-Setball ball sector valve - Manual (Page 5)

5
9.4 To inspect and change the upper stem sealing,
Boxpacking Zebra-CL™
The sealing requires inspection and adjustment when the
valve is taken into operation.
Ensure that the valve is free of pressure.
1. Dismount the actuator.
2. Remove the nuts (18). Lift off the gland cover
(16). Then remove the boxpacking (19A) and
the o-ring (13).
Inspect the primary and secondary exhaust
fuse, see section 9.7.
3. Clean the stem surfaces, gland cover (16) and
the recess in the valve body.
4. Inspect the stem surface thoroughly. It should be
free from marks and scratches.
5. Lubricate the stem with suitable lubrication.
6. Replace the packing (19A) and the greased
o-ring. Then mount the gland cover (16) and
nuts (18).
7. Tighten the nuts (18) until the boxpacking gets in
place and is in contact with both the stem and
valve body. Check the tightness of the packing
and retighten the nuts (18) – if necessary - when
the valve is taken into operation.
9.5 To inspect and change the upper stem sealing,
Boxpacking Safeguard
The sealing requires inspection and adjustment when the
valve is taken into operation.
Ensure that the valve is free of pressure.
1. Dismount the actuator.
2. Remove the nuts (18) and the cup spring (24).
Lift off the gland cover (16). Then remove the
boxpacking (19B) and the o-ring (13).
Inspect the primary and secondary exhaust
fuse, see section 9.7.
3. Clean the stem surfaces, gland cover (16) and
the recess in the valve body.
4. Inspect the stem surface thoroughly. It should be
free from marks and scratches.
5. Lubricate the stem with suitable lubrication.
6. Replace the boxpacking (19B) and the greased
O-ring (13). Then mount the gland cover (16)
and nuts (18).
7. Tighten the nuts (18) until the boxpacking gets in
place and is in contact with both the stem and
valve body. Check the tightness of the packing
and retighten the nuts (18) – if necessary - when
the valve is taken into operation.
9.6 To change the gasket at the lower stem
1. Remove the bolts (20) and the cover (6).
2. Carefully pull out the stem (4) and remove the
bearing in metaloplast (31) and the gasket (7).
Inspect the primary and secondary exhaust
fuse, see section 9.7.
3. Carefully clean the inside of the cover (6) and the
stem (4).
4. Replace the gasket (7) with a new one.
5. Mount the stem (4) with the gasket (7).
6. Fit the cover (6) and tighten the bolts (20).
9.7 To inspect and change the primary and
secondary exhaust fuse.
The locking devices requires inspection after long operating
time and/or many cycles.
1. Remove the cover (6).
2. Carefully pull out the lower stem (4) and remove
the bearing in metaloplast (31) and the
gasket (7).
3. Loosen the bolt (28) and remove the
washer (26).
4. Carefully pull out the upper stem (22) and
remove the stem sealings and bearing.
5. Inspect the bearing seat (9), locking segment (8),
washer (26) and bolt (28). Replace them if they
are worn out.
6. Remount the stem (22), washer (26) and bolt
(28).
7. Grease and remount the locking segments (8) and
bearing seat (9). Ensure that it is properly placed
over the locking segments.
8. Mount the bearing and gland cover.