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AVK SUPPORT
NRS (Non-Rising Stem) VALVE REPAIRS:
STEM/WEDGE, LOWER STEM SEAL COMPONENT
REPAIR:
WARNING: To perform the following steps, be sure the Water
Main Supply Line has been shut off, and that the pressure has
been bled off! Also provide sufficient clearing around the valve
so that no soil or debris may fall into it.
1. Complete steps 1 through 4 in the UPPER STEM SEAL
COMPONENT REPAIR section.
2. Turn the Stem (F333), in a closing direction until it
disengages from the Wedge (F237), and remove from valve.
3. If applicable, for Low Zinc Stems, remove the Lower Anti-
Friction Washer (F235) from the recess in the bonnet (F217).
For Stainless Steel Stems, the Stem Collar and Anti-Friction
Washers are replaced by a two-piece Thrust Collar (F234).
No Anti- Friction are necessary or present. The Lower Stem
Seal O-ring (F232) should be present on the stem and in it’s
own groove, located directly above the threads.
NOTE: On Stainless Steel Stems, the upper three grooves are
for locating the Thrust Collar.
4. Inspect and replace any damaged parts.
NOTE: Use a food grade grease that contains no acetate or
silicone on the new o-rings.
5. Using a small, flat bladed screwdriver, remove the hot melt
glue that covers the Bonnet Bolts (F216).
6. Once the hot melt glue has been removed, use a 3/8”, or
10mm Allen wrench to remove the Bonnet Bolts (F216).
Remove the Bonnet (F217) and Bonnet Gasket (F218) and
set aside.
7. To remove the Wedge (F237) it is sometimes helpful to
thread the Stem (F233) back into the wedge and use the
stem as a handle or lever to extract the wedge. This is
helpful with the larger sizes, (10” and 12”) valves.
8. Carefully inspect the interior of the valve body and remove
any debris.
9. Inspect and replace any damaged parts and re-assemble in
reverse order, torquing the Bonnet Bolts to 40 ft. lbs., in a
diametrically opposed (180 degrees apart) pattern.
9. To replace the protective hot melt glue over the Bonnet Bolts,
use any EPA approved caulk, or hot melt glue.
