Samson 3595, Монтаж и эксплуатация

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9-8 EB 8079 EN
Servicing
plug. This leads to a changed flow rate and
changes the control characteristics of the
valve as a result.
Î
Only apply lapping compound to the
seat ring.
8. Place the seat ring with the gasket into
the valve body. Observe the proper posi-
tion and alignment. The surface sloping
by approx. 20° is the seat of the plug
and must face towards the valve bonnet
(see Fig. 9-4, angle B).
9. Place the cage (both cage parts, if appli-
cable) with the gasket(s) into the valve
body.
10. Place the valve bonnet together with the
plug stem and plug straight onto the
valve body. On doing so, guide the plug
through the cage.
11. Fasten the valve bonnet with two or three
body nuts.
12. Insert a temporary packing into the valve
bonnet to ensure the plug is correctly
aligned during lapping. See sec-
tion 9.4.2.
13. Thread lock nut onto the plug stem.
14. Thread lapping tool onto the plug stem
and lock in place with a lock nut.
15. Perform lapping with short oscillating
strokes. Turn the plug stem by 90 to 180°
back and forth. The weight of the plug,
plug stem and lapping tool create suffi-
cient pressure for the lapping procedure.
16. Clean the seat and plug after lapping.
17. To check the tight shut-off of the lapped-
in parts, hold the externally protruding
plug stem and press the plug by hand in-
to the seat. Apply compressed air to the
inlet side of the valve. Repeat the lapping
procedure, if necessary.
18. Dismantle all parts (including packing)
and clean them thoroughly to remove all
residual lapping compound and lubri-
cant.
19. Clean also the packing chamber thor-
oughly.
20. Apply a suitable lubricant to all the pack-
ing parts and to the plug stem (see the
'Tightening torques, lubricants and tools'
section in the annex).
21. Push the plug stem from below through
the valve bonnet.
22. Carefully slide the packing parts (espe-
cially in the threaded section) over the
plug stem into the packing chamber us-
ing a suitable tool. Make sure to observe
the proper order (see Fig. 9-3).
23. Carefully slide the packing follower
downwards over the plug stem.
24. Place the packing gland with the flat side
facing upwards onto the stud bolts.
25. Thread the nuts of the packing gland on-
to the stud bolts and finger tighten them
clockwise in a crisscross pattern.