Samson 3271 Mounting And Operating Instructions page 48

Servicing and conversion
b) Reversal of the direction of
action from stem retracts to
stem extends
See Fig. 9-5
1. Lift off the top diaphragm case (A1).
2. Pull the actuator stem (A7) together with
the diaphragm plate (A5) and dia-
phragm (A4) out of the bottom dia-
phragm case (A2).
3. Remove the springs (A10).
4. Clamp the actuator stem (A7) into a vise
using protective jaws. Make sure that the
actuator stem is not damaged.
5. Unscrew the collar nut (A15).
6. Take the compressor (A35) together with
the diaphragm plate (A5) and dia-
phragm (A4) off the actuator stem (A7).
7. Remove the shim (A37).
The shim is not required for "stem ex-
tends" direction of action.
8. Place the diaphragm plate (A5) together
with the diaphragm (A4) and compres-
sor (A35) in reverse order onto the actu-
ator stem (A7). Make sure that the seal
lip of the diaphragm (A4) is inserted cor-
rectly between compressor (A35) and di-
aphragm plate (A5).
9. Screw the collar nut (A15) against the
compressor (A35). Observe tightening
torques.
10. Apply a suitable sealant and lubricant to
the actuator stem (A7).
9-8
11. Insert the actuator stem (A7) together
with the diaphragm plate (A5) and dia-
phragm (A4) into the bottom diaphragm
case (A2).
12. Place the springs (A10) into the bottom
diaphragm case, centering them in the
intended recesses.
13. Place on the top diaphragm case (A1).
14. If necessary, preload the springs (see the
'Start-up' section).
15. Fasten the top and bottom diaphragm
cases (A1, A2) together using the nuts
(A21) and bolts (A20). Observe tighten-
ing torques.
16. Type 3271: remove the vent plug (A16)
from the bottom signal pressure connec-
tion (S) and screw it onto the top connec-
tion.
Type 3277: remove the vent plug (A16).
The actuator springs, which now push
against the diaphragm plate from above,
cause the actuator stem to extend. The
signal pressure is connected to the bot-
tom connection (S) on the bottom dia-
phragm case (over the yoke in
Type 3277). As a result, the actuator
stem retracts opposing the spring force
as the signal pressure increases.
17. Affix a new nameplate with changed
symbol and new configuration ID to the
actuator.
EB 8310-4 EN