Masoneilan 21000 Series Top Guided Globe Valve Instruction Manual | 9
Copyright 2023 Baker Hughes Company. All rights reserved.
b
. lnstall plug tip into shank sub-assembly. Hand tighten
and ensure plug tip seats evenly against insert.
For 3" – 8" valves:
a
. Apply a light coat of lubricant to the O-ring and install on
insert retainer.
CAUTION
CAUTION
WARNING
DANGER
Ensure any lubricant used is compatible with service
conditions.
b
. Install new insert on insert retainer and assemble as
shown in Figure 3.
c
. Install plug tip into insert retainer sub-assembly insuring
the plug tip seats evenly on the insert.
F.
Carefully place the plug sub-assembly into a soft jaw vise,
holding the plug by the flats provided on the upper end of the
shank.
CAUTION
CAUTION
WARNING
DANGER
When using a vise to hold the plug, extreme care
must be taken not to damage the plug shank.
G.
Using the appropriate tool used during disassembly, firmly
tighten the plug tip.
CAUTION
CAUTION
WARNING
DANGER
The plug tip must be tightened, allowed to set for
approximately 4 hours, re-tightened, allowed to set
another 4 hours, then tightened one more time. The
purpose of this tightening sequence is to allow the
insert material to “cold flow” into place on the plug
sub-assembly.
H.
Following the above tightening sequence, securely tighten
the set screw down into the plug. Plug is ready for assembly
into the valve.
8. Valve Body Reassembly
After completion of the required maintenance, the valve should
be reassembled using the following procedures:
Note:
If any of the following steps were completed during
maintenance, then proceed to the next step.
8.1 Threaded Trim (Figure 12 or 14)
A.
CIean all gasket mating surfaces.
B.
Apply a small amount of sealant to the seat ring threads and
sealing shoulder. Install seat ring into valve body.
Note:
A sealant compatible with the process should be
applied sparingly.
C.
lnstall and tighten seat ring using wrench used for removal.
7.6.4 Packing Box Efficiency
The constant supervision of the packing box is one of the main
routing operations of the maintenance service. In order to
provide a correct functioning of the valve, the packing should
not be tightened over the compression value sufficient to provide
the tightness. The packing box efficiency is obtained by the
compression of the packing, or by combining it with use of the
lubricant. As it wears, gradually re-tighten the packing up to the
limits of the possible compression. In order to add packing, it is
necessary only to remove the packing follower and flange and
introduce one or two split rings.
Note: In case of urgency, the braided packing of suitable
section can be inserted without removal of the worn
rings. Before this operation, the valve must be put out of
service. If the packing is made up of non-split rings, it may
be necessary to disassemble the valve, remove the worn
packing and reassemble per the instructions.
7.7 Soft Seat Plug (Figure 3)
The soft seat plug used in the 21000 Series valve has a
replaceable insert. To remove and replace the insert, proceed
as follows.
CAUTION
CAUTION
WARNING
DANGER
The shank OD is the plug guide. Extreme care must
be taken to prevent scoring or marring this surface.
Failure to do so could result in damage to the guide
bushing and destruction of the plug. Two flats are
provided for holding.
A.
Loosen set screw until the head of the set screw is flush with
the OD of the shank.
Note:
On 3/4"- 2" size valves, the plug tip has a machined
slot into which a bar can be inserted for removal. On
3"- 6" size valves, the plug tip has two machined holes
into which a tool (fabricated with appropriate size pins)
can be inserted for removal.
B.
Carefully place plug sub-assembly into a soft jaw vise,
holding the plug by the flats provided on the upper end of
the shank.
CAUTION
CAUTION
WARNING
DANGER
When using a vise to hold the plug, extreme care
must be taken not to damage the plug shank.
C.
Using the appropriate tool, unscrew plug tip (counter-
clockwise) from the shank sub - assembly.
D.
Remove insert O-ring (for valve sizes 3"- 8" only) and insert
retainer. Discard existing insert and O-ring.
E.
Thoroughly clean all remaining metallic components
and install new insert and O-ring as follows (according to
valve size):
For 3/4"- 2" valves :
a
. Place new insert on shank and insert retainer as
shown in Figure 3.
