Jordan Valve Mark DBAQ Series Angle Style Control Valve - Manual (Page 4)

-4-
M
ark
DBaQ S
erieS
a
ngle
S
tyle
C
ontrol
V
alVeS
Replacing Packing Continued,
4. Unscrew hex nuts (key 8) and remove the bon-
net off the valve stem. Ensure the valve plug
and stem remain in the body and on the
seat. This will prevent damage to the
seating surfaces as a result of the assembly
dropping from the bonnet after being lifted out.
5. Should the valve plug and stem assembly start
to lift out, use a brass hammer on the
end of the stem and tap it back down. Set the
bonnet on a cardboard or wooden surface
to prevent damage to the bonnet gasket
surface.
6. Upon removing the bonnet gasket (key 5), cover
the opening in the valve body to protect the sur-
face and prevent any debris from getting into
the valve body.
7. Remove the packing flange nuts, packing
flange, upper wiper and packing follower (keys
18, 16, 20 and 21). Carefully push the remaining
parts out from the body side of the bonnet. Take
care not to scratch the packing box wall.
Clean the box and metal parts.
8. Inspect components such as valve stem threads
and packing box for any sharp edges that may
damage the packing. If the surfaces cannot be
improved by light sanding, replace the
damaged parts. Scratches or burrs may
cause packing leakage.
9. Remove the protective covering from the valve
body. Install a new bonnet gasket (key 5).
Ensure the gasket seating surfaces are
clean and clear of debris. Check that the
M-Flat valve plug, and stem assembly
are oriented as shown in Figure 2 when
replacing the bonnet to the valve body. Slide
the bonnet over the stem onto the stud bolts.
10. Replace the packing hex nuts (key 18)
10a. For pre lubricated hex nuts (identi-
fied by black film coating on the
nut threads) tighten the hex nuts
finger tight.
10b. For all other nuts, Jordan Valve rec-
ommends that you lubricate the
stud threads with Never Seez pure
Nickel special lubricant or equiva-
lent.
11. To center trim, the valve will need to be
stroked several times. Using proper
bolting procedures tighten the
nuts to no more than 1/4 of the torque
values specified in Table 2.
12. Increase the torque on each nut by an ad-
ditional 1/4 of the torque value using the
standard crisscross pattern. Repeat this
pattern until the torque values in Table 2
have been reached. Apply the final torque
value again and if any bolts turn, all of the
bolts will require re-tightening.
13. Using the appropriate packing arrange
ment, install new packing and metal pack
ing box parts. It may be necessary to
pre-lubricate packing parts with a silicone
based grease.
14. Using a smooth edged pipe, cautiously
tap each soft packing part into the pack
ing box. To prevent trapping air between
the rings, add one ring at a time, without
forcing them below entrance chamber
of the packing box. With each additional
ring the stack should only be pushed down
the thickness of one ring.
Figure 2: M-Flat Valve Plug Orientation