Baker Hughes Masoneilan 41005 Series, Instruction Manual

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b . Packing Manual Ref 34620 is also available as
an additional aid while completing the packing
installation.
c . The packing should be checked for leakage.
Note: All exposed surfaces of the packing set must
be covered with the lubricant.
d . Packing load should be checked after the valve has
cycled approximately 500 times. Adjust if necessary.
Plant maintenance / operation personnel should
periodically inspect valves to spot leakage. Adjust if
necessary and per OEM recommendations. If leak
is not resolved, packing and any non-confirming
hardware part must be replaced.
5.1.4 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 follow directions to reassemble.
5.2 Repair of Parts
Before re-assembly, the parts must be carefully examined in
order to eliminate any scratched, worn or damaged parts.
5.2.1 Guiding Surfaces
The guiding surfaces of the cage and valve plug, the guide
bushing, and the guiding surfaces of the plug stem and
auxiliary pilot plug must be checked in particular. If there is
only slight damage, a light abrasive can be used.
Otherwise the part must be replaced as soon as possible
(see paragraph “Spare parts”).
Cage
Pilot
Guiding
surface
Guiding
surface
Seating
surface
Figure 2 - Cage and Valve Plug
5.2.2 Seating Surfaces
Valve Plug
Seat Ring
Plug seating
surface
Pilot seating
surface
(41405 only)
Guiding
surface
Guiding surface
Seating surface
Seating surface
Seat ring seating surface
31°30'
32°30'
62°30'
57°30'
29°30'
30°30'
Figure 3 - Seating Surfaces
Inspect all seating surfaces per Figure 3 which represents all
plug and seat types.
For type 41405 valves, if the surface of the auxiliary pilot
plug (20) is damaged, the auxiliary pilot plug must be
replaced (see paragraph “Spare parts”).