Owner's manual

6. Rdhg up on diaphragm (8). remove
diaphragm and connecting link assembly
from receiver My.
7. Remove calibration spring (21).
8. Install new calibration spring (21). Make
sure spring washer (22) is in bottom of
spring socket (20).
9. Remove connecting link (13) from
diaphragm by toming upper ball socket not
(12) countercbx%vise.
10. Remove spring nut (11) from diaphragm
stud (7). Separate diaphragm (8). stop ring
(9), and shield (10).
11. Assemble new diaphragm (8) with stop ring
(9) and shield (10). Secure in place with
diaphragm stud (7) and spring nut (11).
12. Install connecting link (13) on new
diaphragm assembly securing with upper
ball socket not (12).
13. Place diaphragm assembly and connecting
lii in receiver so connecting Iii is aligned
with pilot valve stem assembly (26).
14. Align edges of diaphragm (8) with stop ring
(9) to make an air tight seal.
15. Place zero balance spring (6) on top of
diaphragm (8).
16. Making sore diaphragm is not folded or
pinched, replace diaphragm cover (5) and
align sealing edge of diaphragm cover on
top edge of diaphragm.
17. Secure diaphragm cover (5) to receiver body
(25) with hex head cap screws (3) and
washers (4). Fit tighten screws until hand
tight. Then snug screws down and tinally
complete tightening in a diagonal pattern.
Toque to 11 foot-lbs (1.52 kg-m).
18. Carefully hold upper end of pilot valve stem
assembly (26). Tarn connecting link’s lower
ball socket not (14) clockwise and secure
connecting link (13) to pilot valve stem
assembly.
19. Reinstall 90” elbow (1) and signal air tubing
(21.
20. Test for leakage around diaphragm cover
and receiver body. Use a leak detector such
as “snoop”, and send an air pressure signal
to power positioner. If leak is detected,
repair as necessary.
21. Refer to paragraph 4-2 and calibrate stroke
of power positioner.
22. Return power positioner to service.
e. Cylinder. Use the following procedure to
disassemble and reassemble the power cylinder
on model PP405TR power positioner. Replace
items that are damaged or worn beyond a
serviceable condition determined by
troubleshooting or by inspection. Replace cylinder
head gaskets each time cylinder is disassembled.
WARNING
Before performing any maintenance or
repair action on power positioner, shut off
supply air, signal air, and any electrical
supply or electronic signals to power
positioner. Isolate power positioner from all
systems connected to the power positioner.
Severe injury or death may result from
large torque power positioner is capable of
producing, or from electrical shock.
1. Remove power positioner from sewice.
2. Shot supply air valve and set signal air
pressure to 0 psig. Open bypass valve.
WARNING
Residual air must he bled off of cylinder
before removal of cylinder head. If air is not
bled off, eye injury may result.
3.
Bleed residual air through pilot valve supply
air connection.