A11 Valve
13
CAUTION
If a vise or other clamps are being
used, be sure damage is not done to
the flange gasket sealing area of the
valve body.
7. Manually rotate the valve shaft to turn the disc
clockwise to meet the seal.
8. Tap the disc with a rubber mallet to drive it
against the internal travel stop. When the disc
makes contact with the stop, manually rotate the
disc counter-clockwise back out of the seal to a 90
_
open position. Repeat steps 7 and 8 three times.
9. The final seating of the retaining ring screws can
be done. For the screw torque values, refer to
table 6. The seal is now fully installed and the valve
may be closed for installation or storage.
Cryogenic Seal Installation
1. Locate the replacement seal ring (key 8) and note
the shape of the ring. The ring is wider across one
edge diameter and narrower across the other edge
diameter as shown in figure 6. Around the outside
circumference is one wide groove.
For Kel-F seals with aluminum backup rings
only:
Now, locate the replacement V-ring. Please
notice that the V-ring is similar in diameters to the
seal ring. Place the V-ring down onto the seal ring
with the larger diameter of the V-ring going first. Be
sure the larger diameters on both rings are down.
2.
For all types:
Install the seal ring (or seal ring
and V-ring) in the valve body by first placing the
wider outside diameter of the seal ring into the T-slot
area of the valve body. The seal ring with or without
a back-up ring will fall into place.
3. Once the seal ring (or seal ring and V-ring) have
been fully installed into the valve body T-slot, the
retaining ring gasket can be installed.
CAUTION
This gasket is a thin graphite material.
Take care to avoid damaging the
gasket. However, punch one initial
screw hole through the gasket for
alignment purposes.
4. Install the retaining ring and align the screw holes
in the retaining ring with the holes in the valve body.
Install the first retaining ring screw through the
punched hole in the ring gasket. Install the other ring
screws by pushing the screws through the graphite
gasket and threading them into the screw holes in
the valve body.
5. Tighten the retaining ring screws just enough to
eliminate vertical movement of the retaining ring. Do
not tighten the retaining ring screws.
WARNING
Avoid personal injury or property
damage caused by the impact of a
falling or tipping large valve. Large
valves must be properly supported
during maintenance.
6. To complete this step, stand the valve up.
Support the valve securely using methods
appropriate for the valve size.
CAUTION
If a vise or other clamps are being
used, be sure damage is not done to
the flange gasket sealing area of the
valve body.
7. Manually rotate the valve shaft to turn the disc
clockwise to meet the seal.
8. Tap the disc with a rubber mallet to drive it
against the internal travel stop. When the disc
makes contact with the stop, manually rotate the
disc counter-clockwise back out of the seal to a 90
_
open position. Repeat steps 7 and 8 three times.
9. The final seating of the retaining ring screws can
be done. For the screw torque values, refer to
table 6. The seal is now fully installed and the valve
may be closed for installation or storage.
Valve Shaft/Disc Pin Unit Maintenance
Valve Shaft/Disc Pin Unit Removal
1. Rotate the disc (key 3) 180
_
counterclockwise
from the full closed position.
2. Place the open valve horizontally on a suitable
work surface with the retaining ring (key 2) facing
upward. Be sure to properly support the valve with
blocks while the shaft is being removed.
