Baker Hughes Masoneilan 41005 Series, Инструкция по эксплуатации

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B. Check that the exposed part of the valve plug
stem (B150) is clean enough for the bonnet (B003) to
be removed easily.
C. Remove the body stud nuts (B014).
D. By means of a Lifting Lug secured instead of the
actuator, lift the bonnet (B003) up and separate it from
the valve body (B001). During this operation, the valve
plug stem (B150) must be pushed downwards so that
the valve plug remains in the valve body (B001).
E. Remove the the body gasket (B015).
F.
In the case of type 41305 valve, remove the valve plug
stem (B150) and valve plug (B112) assembly from
the cage by pulling the valve plug stem upward, then
remove the cage (B107).
G. Remove the trim retainer (B105) followed by the cage
(B107) and the seat ring gasket (B103) from the valve
body (B001).
H. Remove the packing (B207, B208), and the packing
bushing (B203) from the bonnet (B003).
3.3 Disassembly of Valve Plug Stem
The valve plug stem is screwed and pinned into the valve
plug (B112).
To dismount the stem, the valve plug must be held as
indicated below, taking care not to damage the guiding
surfaces; the plug stem pin (B903 ) is then removed. By
means of flats or using a nut and counter-nut on the end
of the stem, unscrew the stem taking care not to apply a
bending moment which could deform it.
Figure 1 - Valve Plug Stem
4. Maintenance and
Repair
4.1 Preliminary Controls
Before reassembly, check parts and the materials for
conformity to the bill of material call out. Inspect inside of
body (B001), Bonnet (B003), Cages (B107, B110) and plug
(B112) for cleanliness.
Remove any foreign matter and clean the gasket surfaces.
Inspect body (B001), Bonnet (B003), Cages (B107, B110),
gaskets (B103, B108, B118, B015), plug (B112), plug stems
(B150), and bushings (B203) for nicks, scratches, burrs,
sharp corners, etc., on sealing and sliding surfaces including
packing box.
Important:
During assembly, care must be exercised to
prevent damage to these parts.
Since 41005 API 6A are high pressure valves, ensure there
is no damage to the sealing surfaces. Performance of
gaskets and seal are strongly linked to surface roughness.
4.2 Packing Box
Prior to assembly the packing:
• Ensure there are no nicks or scratches on the stem and
packing box inside diameter packing area.
Violation of any of these requirements is cause for stem or
packing box rejection
Tightness of the packing box is obtained by compression
of the packing rings (B207) and anti-extrusion rings (B208).
Compression must be achieved by evenly tightening the
packing flange nuts (B221) on the packing flange (B219).
Periodical retightening of the packing flange nuts is required
to maintain tightness.
Make sure that the packing is not over tightened as this could
prevent smooth operation of the valve.
If a leak persists after the packing has been compressed to a
maximum, the packing needs to be changed.
4.2.1 PTFE Based packing
A. Unscrew and remove the packing flange nut (B221) and
packing flat washer (B921a)
B. Lift the packing flange (B219) up along the valve stem
C. Extract and remove the packing rings (B207) and anti-
extrusion rings (B208), taking care not to damage the
sealing surface of the packing box lantern or the valve
plug stem.
D. Replace the packing rings, with the cut in each ring
placed about 120° from the next, pressing them down one
at a time and respecting the table below
Cylindrical machining diameter of the jaw =
plug shank diameter: Dia. A
Soft metal
vise draw
Do not tight
on the plug
skirt
Tight only on
this no guiding
surface
Stop pin
integrated in
vise jaw and
inserted into a
plug hole