Flowserve Valtek Valdisk Control Valves - Manual (Page 5)

10-5
insert the shaft through the body, bearings and disc.
5. Position the disc in the body, making sure it will rotate
in the proper direction with respect to the bodyís internal
disc stop. Slide the shaft through the body, bearings and
disc.
CAUTION: Exercise care while sliding the shaft into the
sliding stem shaft bearings to avoid damage to both the
shaft and bearings.
6. Insert new taper pins and drive them firmly into place in
the side opposite the stop.
7. Slide the packing retainer, lower packing, packing spacer,
upper packing, and packing follower over splined end of
the shaft and into the body. Typical packing configurations
are shown in Figure 3.
NOTE:
CAUTION: Since the sealing on V-ring packing takes
place at the feather edge, it is important to avoid dam-
age to that edge.
8. Reinstall the end plug (or replace the end seal and reinstall
the bolted flange).
9. Reinstall the gland flange and packing nuts. Tighten
packing evenly to slightly over finger-tight.
CAUTION: Do not overtighten packing. This can cause
excessive packing wear and high shaft friction, which
may impede shaft rotation.
7. Push the packing and bearings out of the body using a
dowel of appropriate diameter. Push the packing from
the center of the valve.
Reassembling the Body
To reassemble the body sub-assembly, refer to Figures 1, 2,
3, and 5 and proceed as follows:
1. Clean all parts.
2. Check the disc seating surface to make sure it is smooth
and free of scoring and scratches.
CAUTION: Damaged or dirty seat surfaces can cause
excessive seat wear and high torque requirements.
Damaged discs should be replaced.
3. Inspect shaft for scratches or galled surfaces. For
maximum performance, Valdisk shafts are machined to
a very smooth finish. If damage exists, replace the shaft
or contact factory representative.
NOTE: Disc and shaft are interchangeable in recent de-
signs. Replacing the disc does not require replacing the
shaft. Earlier designs require that the disc and shaft be
machined together. Contact the factory for matched disc
and shaft.
4. Insert new sliding stem shaft bearings into the body. (A
press may be required with some designs.)
NOTE: Earlier Valdisk designs require the disc to be aligned
with the body in such a way that it can rotate properly.
Align the shaft bearings on either side of the disc and
Figure 3: Typical Packing Configurations
SafeGuard / SureGuard
Fire-safe Option
(live-loading omitted)
SureGuard
Standard Square Standard Single "V" Twin "V"
SafeGuard
(packing studs rotated 45 degrees)
Twin "V" with Lubricator