-
Pull valve stem assembly slowly through
opening in shell until the front part of the
bladder assembly is clear of the opening.
Begin depressing and collapsing bladder
to expel gas while pulling it slowly. This will
minimize drag at the shell opening until
bladder assembly is completely out of
shell.
-
With bladder assembly in the work area,
remove gas plug.
-
Remove “O” ring and back-up ring from
valve stem.
Cleaning & Inspection
-
After disassembly, clean all parts with an
approved cleaning solution (such as
varsol).
-
Blow all the parts dry with air pressure and
place them where they will be free from
foreign matter.
-
Install pipe plug (1/8" NPT) and gas valve
on valve stem.
-
Inflate bladder assembly to 3 PSIG with
dry nitrogen. Inspect bladder for wear or
damage.
-
Check all elastomer items for deterioration,
abrasion marks, cracks, holes,
bubbles or any similar defects.
-
Replace all “O” rings and any other items
deemed unsuitable for further usage.
Reassembly
-
With bladder assembly in work area, install “O” ring seal and back-up ring on
valve stem and apply light coating of lubricant
to shell opening.
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- Install bladder puller with 1/8" NPT intoappropriate port on valve stem, then expel all air to completely collapse bladder. Fold bladder longitudinally into compact roll. To maintain rolled condition of bladder, install gas valve and 1/8" NPT pipe plug into appropriate ports on valve stem to prevent atmospheric air from entering the bladder. Also, encircle bladder with string and tie with slip knots in approximately four places. This will ensure proper insertion of bladder into shell opening with a minimum amount of drag.
- While holding bladder puller and folded
bladder, insert bladder into shell and continue
until valve stem assembly is completely
inside of shell. CAUTION: DO NOT
ALLOW WEIGHT OF VALVE STEM ASSEMBLY
TO DROP INTO SHELL. (NOTE:
While inserting bladder into shell, remove
strings as required to permit bladder to unfold
inside shell.)
- Open gas valve.
- With dry nitrogen, slowly pressurize the
bladder with sufficient pressure (approximately
5 PSIG) to inflate it until top of bladder
has a smooth, wrinkle-free spherical
surface.
- Release a minimal amount of gas pressure
to allow the bladder and valve stem to be
pushed completely inside the shell again.
(NOTE: Bladder must remain inflated.)
- Apply light coating of lubricant to inside
opening of gas plug. While holding bladder
puller, pass rope through opening. Install
gas plug so that it bottoms out on
valve stem.
- Continue holding bladder puller and pass
anti-extrusion ring over the rope, bending
ring at the middle and holding it at an
angle. Insert anti-extrusion ring into the
shell opening and install it against shoulder
on gas plug.
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