SD73
MAINTENANCE GENERAL
Clean, dry, oil-free instrument air will reduce most
problems associated with pneumatic instruments.
Refer to INSTRUMENT AIR REQUIREMENTS.
If these requirements are observed, no routine
maintenance is recommended. Cleaning the
plunger is to only maintenance which may be
required on an occasional basis.
The system should be shut down or the valve
isolated from the system before service or removal
of the positioner is accomplished.
CLEANING (Refer to parts list)
The plunger can be cleaned without dismantling
the positioner. Use the following procedure:
1.
Turn off the supply air.
2.
Remove the positioner top cover.
3.
Remove the retaining nut.
4.
Remove the plunger.
5.
Use a non-abrasive solvent to clean the
plunger.
6.
Replace the plunger.
7.
Replace and tighten the retaining nut.
8.
Replace the top cover.
DISASSEMBLY (Refer to parts list)
1.
Loosen the six socket head mounting screws
holding the positioner to the actuator.
2.
Remove the positioner.
3.
Remove the two body screws holding the
diaphragm stack assembly to the positioner
body (located on the underside of the stack).
4.
The diaphragm stack assembly can be further
disassembled by removing the diaphragm jam
nut.
ASSEMBLY (Refer to parts list)
To assemble, reverse the disassembly procedures.
Take care to insure proper alignment of the
diaphragms and rings. When tightening the jam nut
on the diaphragm assembly, make sure the
diaphragms do not rotate out of position.
Figure 3 Range and Zero Spring Color Codes
An alignment slot is provided on the rings to
facilitate proper assembly.
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