Flowserve PM15E Electro-Pneumatic Valve Positioner - Manual (Page 8)

13. MAINTENANCE
A. Pilot Valve
To remove the pilot valve for cleaning or inspection, remove the
screw (1) and carefully lift out the complete assembly (2). Gently
remove the spool (3) from the block and clean the parts, using
methylate cleaner or similar. Blow parts dry with compressed air.
Should the parts show signs of wear, a new assembly is
recommended. Mixing spool valves and valve bodies may result in
very high bleed rates and poor performance. Check the O-rings,
then secure and install the pilot valve assembly to the positioner
unit and secure it with the screw (1). Make sure that the leaf
spring (4) on the balance arm (5) is properly fitted in the groove
on spool (6). Check again to ensure smooth operation of the
assembly.
To maintain original factory performance specifications, use only
spool valve assemblies supplied by Flowserve.
B. Diaphragm
The I/P unit must be removed to access the diaphragm. (See
previous section.) Then loosen screws (1) and remove the
diaphragm cover (2). Loosen screw (3); diaphragm (4) and
washers (5) can be removed.
When installing the diaphragm, make sure to place one washer on
each side of the diaphragm. Make sure that the raised circle on
the washers is facing the diaphragm.
Install the screw (3) and tighten.
Check the O-ring on the diaphragm cover (2), then install and
secure the cover with screws (1).
C. Feedback Spring
Once the front cover and indicator are removed, the feedback
spring can be easily accessed.
Hold the spring (1) from the top, pull down and out.
When installing, hold the assembly at the top, guide the lower part
to position on the zero screw, then press down until it fits easily
under the balance arm (2). Make sure that the assembly is aligned
properly against the lower arm and the notch is engaged in the tab
on the balance arm (2).
Flow Control Division
Worcester Controls
8 Model PM15E Electro-Pneumatic Valve Positioner WCAIM2017
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