38
EB 8091-1 EN
Servicing
7.3 Replacing the seat and
plug
Risk of control valve damage due to incorrect
service or repair.
Seat and plug can only be replaced when all
the following conditions are met:
−
The valve does not have a bellows seal.
To replace seat and plug in other valve ver-
sions, contact SAMSON's After-sales Service
department.
Incorrect control due to a combination of
trim parts that do not match each other.
The trim parts (seat, plug, anti-rotation fix
-
ture, and body gasket) are matched to ex
-
actly fit each other. The anti-rotation fixture
must also be exchanged on replacing the
seat and plug. The trim parts are delivered
together and marked accordingly (see sec-
tion 2.3).
Only install matching trim parts.
Risk of damage to the facing of the seat and
plug due to incorrect service or repair.
−
Always replace both the seat and plug.
−
Only install matching trim parts (see sec-
tion 2.3).
7.3.1 Standard version
1. Remove the actuator from the valve. See
associated actuator documentation.
2. Loosen the slotted nut (11) at the valve.
Remove the yoke (13) from the interme-
diate piece (4).
3. Unscrew the fillister head screw (6) on
the anti-rotation fixture (2.4). Remove the
anti-rotation fixture (2.4) from the inter-
mediate piece (4).
4. Unscrew the intermediate piece (4) from
the body (1). Remove the intermediate
piece (4) together with plug (2.1) from
the body (1).
5. Replace gasket as described in sec-
tion 7.1.1.
6. Unscrew the hex nuts (20) from the plug
stem (2.1). Remove the stem connector
parts.
7. Unscrew the threaded bushing (12).
8.
Replace the packing. See section 7.2.
9.
Unscrew the seat (2.2) using a suitable
tool.
10. Apply a suitable lubricant to the thread
and the sealing cone of the new seat.
11. Screw in the seat (2.2) using a suitable
tool. Observe tightening torques.
12. Pull the plug with plug stem (2.1) out of
the intermediate piece (4).
13. Apply a suitable lubricant to the new
plug stem (2.1) and thread of the inter-
mediate piece (4).
14. Slide the new plug with plug stem (2.1)
into the intermediate piece (4).
NOTICE
!
NOTICE
!
NOTICE
!
Summary of Contents for 3510
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