Service Work For Version With Type 3379 Actuator; Replacing The Packing - Samson 3349 Mounting And Operating Instructions

Servicing
9.5 Service work for version
with Type 3379 Actuator
Note
To prevent the actuator stem from rotating, a
locking pin with 3.5 mm diameter is re-
quired. The locking pin (item no. 1281-
0066) can be ordered from SAMSON.
9.5.1

Replacing the packing

1. Undo the screws (34) on the valve bon-
net (20).
2. Lift the actuator (A) and valve bonnet
(20) together with the plug stem (3), plug
(2) and diaphragm (24) off the body (1).
3. "Actuator stem extends" fail-safe ac-
tion: guide the locking pin (Ø 3.5 mm)
through the hole located in the bottom
actuator section and the actuator stem.
"Actuator stem retracts" fail-safe action:
apply 6 bar signal pressure to the actua-
tor. Guide the locking pin (Ø 3.5 mm)
through the hole located in the bottom
actuator section and the actuator stem.
4. Unscrew the plug stem (3) together with
plug (2) and diaphragm (24) off the ac-
tuator stem and pull it out of the valve
bonnet (20).
5. Unscrew the actuator (A) from the valve
bonnet (20).
6. Remove locking pin.
7. Compress the packing using a suitable
tool and remove the snap ring (42).
46
8. Pull the entire packing out of the packing
chamber using a suitable tool. Renew the
damaged parts and carefully clean the
packing chamber.
9. Check the plug and diaphragm for dam-
age. Replace them, if necessary (see sec-
tion 9.5.2).
10. Push the plug (2) together with plug stem
(3) and diaphragm (24) into the valve
bonnet (20).
11. Carefully slide the packing parts over the
plug stem into the packing chamber us-
ing a suitable tool.
12. Compress the packing using a suitable
tool and insert the snap ring (42).
13. Screw the actuator (A) onto the valve
bonnet (20).
14. "Actuator stem extends" fail-safe ac-
tion: guide the locking pin (Ø 3.5 mm)
through the hole located in the bottom
actuator section and the actuator stem.
"Actuator stem retracts" fail-safe action:
apply 6 bar signal pressure to the actua-
tor. Guide the locking pin (Ø 3.5 mm)
through the hole located in the bottom
actuator section and the actuator stem.
15. Apply a suitable lubricant to the actuator
stem.
16. Screw the plug stem (3) together with
plug (2) and diaphragm (24) onto the
actuator stem. Observe tightening
torques.
17. Remove locking pin.
EB 8048-21 EN