IOM-ALR-1
4
Figure 1:
Dynamic Side Seals
Type OR
— O-Ring
Dynamic Seal
Type CW
— TFE Cap
Dynamic Seal + Wiper
Type UC
— U-Cup
Dynamic Seal
B. Main Regulator Disassembly:
1. Shut down system in accordance Section VI.
2. Disconnect the external sensing line, if in-
stalled. Disconnect tubing from the auxiliary
air supply where it connects to the cover dome.
3. Though it is possible to disassemble the valve
unit while installed in a pipeline, it is rec om-
mend ed that maintenance be done in a shop
when possible. The instructions hereafter will
assume shop disassembly. Remove valve
from pipeline.
4. Place the regulator body in a vise with the
cover dome (25) upwards.
5. Loosen the diaphragm flange bolts (11) and
nuts (12) uniformly.
6. Place matchmarks on body (23) and cover
dome (25) flanges. Remove cover dome (25).
WARNING
SYSTEM UNDER PRESSURE. Prior to per form ing any
maintenance, isolate the reg u la tor from the system and
relieve all pressure. Failure to do so could result in
personal injury.
Tubing Connection
7. Hold the milled “flats” on top of the valve
plug (20) stationary, rotate the di a phragm
lock nut (7) CCW to remove.
8. Remove upper diaphragm plate (8).
9. Remove diaphragm (9) and o-ring upper stem
seal (14.1). Examine diaphragm to determine
whether failed; determine if op er at ing condi-
tions are ex ceed ing pressure, pressure drop
or temperature limits.
Figure 2
Unloader
Gauge
Filter
Filter
Ori
fi
ce
Bug Vent
