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Wipe down one of the body ball seals (item 10) and then place it into the
bottom seat of the valve body (item 4), flat side donwards. Be very careful to
avoid damaging the seat during installation.
TIP:
For valve assemblies using SS/TF seats, apply a thin layter of grease
(such as Panef Petrolatum) to the chafer portion of the seat (item 10).
CAUTION:
If working with an A-522 the ball seals are the same for the
body and the cap, but if working with an A-522A make sure to identify the
body ball seal correctly, not to be confused with the cap ball seal (item
15).
Figure 4-23 Install Ball Seal
If not done in prior inspection, clean the valve ball (item 3) with warm water
and soap, or immerse it in a heated ultrasonic bath (125°F - 150°F) for five (5)
minutes. Then rinse the ball with clean, cold water. Dry it with a lint-free coth.
NOTICE:
Allow the valve ball to return to room temperature before
continuing.
Perform a final check of the valve ball (item 3) for scratches or nicks. Run
your fingernail around both rims of the ball. Any damage is cause for
rejection.
Figure 4-24 Check for Nicks
Rotate the valve stem (item 2) so that it end that engages the ball (item 3) slot
is oriented vertically.
Figure 4-25 Orientate Vertically
Carefully place the valve ball (item 3) into the valve body (item 4), aligning the
ball slot with the stem end.
For valves with vented balls, the “Tank-Side Only” stamp on the ball near the
vent hole should be oriented facing down when installing the ball.
Figure 4-26 Install Valve Ball
Check the inside surfaces of the cap plate for nicks and debris
.
10
4
3
A-520/A-522/A-522A
, Rev. 3.0
