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EWNS Valve
March 2022
Figure 5. Bolting Diagram
Figure 6. Typical Load Scale
22. Lubricate the packing nuts (key 14) with Nuclear Grade anti-seize lubricant (key 27) and tighten them hand‐tight.
23. The load scale (key 22) is used to indicate compression on the Belleville springs. Position the qty-2 load scales (key
22) by slightly loosening the mounting screws (key 21). Align the bottom edge of the load scale with the indicator
disk and retighten the screws. Figure 6 illustrates the load scale properly adjusted before the nuts have been
tightened and with the Belleville springs (key 20) not compressed.
24. Tighten the packing nuts (key 14) while observing the two load scales (key 22) to make sure the flange (key 9) is
tightened evenly. Be sure to keep the follower (key 17) centered on the stem (key 4) while tightening the nuts.
Tighten the nuts alternately and evenly, keeping the flange parallel with the valve, until the indicator disk (key 19)
aligns with the maximum compression line on the load scales.
25. The packing is now properly loaded and the packing nuts (key 14) do not need to be retightened unless the
indicator (key 19) begins to approach the minimum compression line. After the valve has been in service for awhile,
visually check the load scale to determine loading. Under normal conditions, the packing nuts should not require
retightening for the life of the packing.
Trim Removal
Key numbers referenced in this procedure are shown in figure 9 except where indicated.
1. Remove the actuator and bonnet by following steps 1 through 9 of the replacing packing procedure. Observe all
warnings and cautions.
12
A4990‐2
STEM SIZE
MAXIMUM SPRING LOAD
MINIMUM SPRING LOAD
ZERO SPRING LOAD
(PACKING NUTS FINGER‐TIGHT)
Instruction Manual
D103551X012
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