Reassembly - Flowserve Worcester V-Flow 51 Series User Instructions

k) All sealing faces on the body, connector and ball must be checked for
corrosion, erosion and scratches. If damage is found or there is any reason to
believe that a part is damaged, replace the part.
l) Valve parts should be cleaned using a suitable degreasing agent. Hard
deposits can be removed using stainless steel wire wool. Care should be
taken to avoid damaging sealing faces.
9.2

Reassembly

a) Ensure that the repair kit and/or spare parts are suitable for the valve being
refurbished.
b) Cleanliness is essential for long valve life. The seats may be lightly lubricated with
a light oil to aid bedding in. Ensure that the lubricant is compatible with the
pipeline media, and the pressure and temperature of the application.
c) Fit a new thrust seal on the stem (see section 11) and insert the stem through the
valve body from inside the valve cavity. Tweezers may make it easier to do so on
DN 15 valves.
d) Fit the new gland packings into the body recess and the gland and the new
Belleville washers (with their outer edges touching) on the stem.
e) While preventing the stem from turning, tighten the gland nut to the correct
torque (see section 10.1). Operate the stem several times and re-adjust the gland
nut to the specified figure. Over-tightening of the gland nut will reduce the life of
the stem assembly.
f) Fit the locking clip correctly as shown in Figure 2.
g) Fit the wrench assembly (if required).
h) Fit the graphite or PTFE seal into the recess in the back face of the metal seal.
Apply Bentone Grease No. 1 to both sides of the seat and the exposed back
face of the seal. Fit the metal seat into the valve body. If the seat is
characterised, (i.e. 30°V), ensure that the slot in the outside diameter locates
onto the orientation pin in the body.
i) Apply Dow Corning DC200 to the metal seated side of the ball only and
assemble into the valve body.
Worcester V-Flow 51 / 52 Series User Instruction – WCENIM0026-01
Figure 2 Fitting the locking clip
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