Samson 3595, Монтаж и эксплуатация

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EB 8079 EN 9-7
Servicing
ing a suitable tool. Make sure to observe
the proper order (see Fig. 9-3).
7. Carefully slide the packing follower
downwards over the plug stem.
8. Place the packing gland with the flat side
facing upwards onto the stud bolts.
9. Thread the nuts of the packing gland on-
to the stud bolts and finger tighten them
clockwise in a crisscross pattern.
9.4.4 Lapping the seat and
plug
Superficial damage (scratches or scoring) on
the sealing face of the seat and plug may
cause tight shut-off between the seat and
plug to be impaired. The unevenness on the
sealing faces of the seat and plug can be
smoothed by lapping.
A
B
1 /
64
"
1
/
32
"
Plug
Seat
ring
Facing
Fig. 9-4: Plug and seat ring
The angle A of the plug must be slightly
smaller than the angle B of the seat ring. For
example, the plug's angle must be 20° when
the seat ring has an angle of 22°.
If the facings have deep scratches or are
very uneven, the seat and plug must be re-
worked or exchanged.
Î
Contact SAMSON's After-sales Service
department when reworking is required.
Necessary conditions for lapping
In addition to preparation before performing
service work, the following points are re-
quired for lapping:
− The lapping compound is provided (see
the 'Tightening torques, lubricants and
tools' section in the annex).
− A suitable lapping tool is provided.
Lapping the seat and plug
1. Unthread the nuts of the packing gland
from the valve bonnet.
2. Remove the packing gland and packing
follower.
3. Pull the plug stem together with the plug
downwards out of the valve bonnet.
4. Pull all the packing parts out of the pack-
ing chamber using a suitable tool.
5. To make it easier to move the plug stem
during the lapping procedure, lightly lu-
bricate the plug stem (see the 'Tightening
torques, lubricants and tools' section in
the annex).
6. Push the plug stem from below through
the valve bonnet.
7. Apply the lapping compound to the fac-
ing of the seat ring.
Risk of valve damage due to lapping com-
pound being applied to the plug.
The inside surfaces of the cage parts will
also be ground during the lapping proce
-
dure if lapping compound is applied to the
NOTICE !