Masoneilan 49000 Series Energy Management Control Valves | 5
Copyright 2020 Baker Hughes Company. All rights reserved.
By means of flats or using a nut and counter-nut on the end of the
stem, unscrew the stem from the plug taking care not to apply a
bending movement which could deform it.
Maintenance & Repair
The purpose of this section is to provide recommended
maintenance and repair procedures. These procedures assume
the availability of standard shop tools and equipment.
Maintenance
Packing Box
Tight sealing within the packing box is obtained by compression
of the packing (15). Compression must be achieved by evenly
tightening the packing flange nuts (19) on the packing flange (17).
Periodic re-tightening of the packing flange nuts may be required
to maintain proper sealing.
CAUTION
CAUTION
WARNING
DANGER
Be careful not to over tighten the packing as this
could prevent proper operation of the valve. If leakage
persists after maximum packing compression, then the
packing needs to be changed.
PTFE Packing
Carbon/PTFE and pure PTFE packing rings are cut in such a way
that they can be replaced without having to separate the valve plug
stem from the actuator stem.
1. Unscrew and remove the packing flange nuts (19).
2. Lift the packing flange (17) and packing follower (16) up along
the valve stem (8).
3. By means of a puller, remove the packing (15) being careful
not to damage the sealing surface of the packing box or the
valve plug stem.
4. Replace the packing rings, placing the cut in each ring about
120° apart from the adjacent ring. Press rings in one at a time.
5. Reassemble the packing follower (16) and the packing flange
(17).
6. Tighten the packing flange nuts (19) without over compressing
the packing rings.
7. Put the valve back into service and check for leakage.
8. Tighten packing flange nuts (19) as required.
Valve with Graphite Packing
To replace Graphite packing, it is necessary to separate the valve
plug stem from the actuator stem.
1. Remove the packing flange nuts (19) from the packing flange
studs (18).
2. Lift the packing flange (17) and packing follower (16) up along
the valve stem (8).
3. By means of a puller, remove the packing (15) being careful
not to damage the sealing surface of the packing box or the
valve plug stem.
4. Replace the packing (15). Press a back-up ring (carbon/
graphite/Inconel braided ring) into the bonnet (2). Next press
the expanded graphite rings into the packing area one at a
time. Press an additional back-up ring into packing area.
5. Reassemble the packing follower (16) and the packing flange
(17).
6. Tighten the packing flange nuts (19) without over- compressing
the packing rings.
7. Open and close the valve several times then retighten the
packing as required.
8. Put the valve back into service and check for leakage.
9. Tighten packing flange nuts (19) as required.
Repair of Parts
Prior to reassemble, examine parts carefully for any scratches,
unusual wear, or other damage.
Guiding Surfaces
Guiding surfaces of the cage, valve plug, guide bushing, plug
stem, and auxiliary pilot plug must be checked. See Figures 2
and 3. If there are only slight wear indications, then gently use a
light abrasive, such as fine grit sandpaper, to smooth out guiding
surfaces. Parts with greater damage or wear on the guiding
surfaces must be replaced.
Seating Surfaces
The seat ring seating surface and valve plug seating surface must
be completely free of dents, wear, or scratches. Consult factory
should you see any signs of slight deterioration prior to attempting
touchup. If a slight defect exists on either the seat ring seating
surface or the valve plug seating surface, lapping can be applied
per the following instructions.
1. CIean body gasket surface areas.
2. Install a new seat ring gasket (10B).
Note : Seat ring gasket (10B) is temporarily placed to hold
the seat ring during lapping.
It is imperative to use a new gasket or a test part having
the same geometrical characteristics in order to insure
the correct position of the seat ring during lapping.
Figure 2
