IOM-48
13
Section IV.A.4. for the corresponding actual
benchset range of the actuator being ser viced,
and test for leakage at upper casing (1) to
lower casing (2) joint. Also test for leakage at
man u al handwheel operator (MHWO), ro tat-
ing handwheel (58) in and out several times
dur ing the test.
25. Release all air pressure into actuator upper
casing (1); remove air source from 1/4" FPT
connection.
wheel (58.1) end) back into the handwheel
gland (67). When stem (58.2) protrudes far
enough through gland (67), re lo cate locking
pliers to opposite end and ro tate stem (58.2)
until stem (58.2) fully dis en gag es.
12. Remove O-ring (62) from handwheel gland
(67).
13. Remove O-ring (63) from handwheel stem
(58.2).
14. Place parts (58.2) (59) (60) (64) (67) into a
suitable solvent and clean as much as pos-
si ble, remove parts and allow to dry.
15. Inspect handwheel stem (58.2) with em bed ded
ball (64) for wear on ball (64). If ball (64) is
worn, or threads of stem (58.2) are dam aged,
replace handwheel sub-assembly (58); i.e.
parts (58.1) (58.2) and (64).
16. If handwheel gland (67) shows signs of wear
in female threads (i.e. loose gauging), replace
handwheel gland (67) and self-tapping slot-
ted-head screw (65). NOTE: A re place ment
handwheel gland (67) will require drilling a
new 5/32" x 1-1/16" (4mm x 25.5mm) deep
hole into the lip of the upper casing (1).
17. Install new O-ring (63) onto handwheel stem
(58.2).
18. Install new O-ring (62) onto handwheel gland
(67).
19. Place a thin coat of lithium grease on the
handwheel stem O-ring (63) and the im me di-
ate surrounding area of the handwheel stem
(58.2).
20. Engage the handwheel stem (58.2) into the
gland’s (67) underneath side. When the hand-
wheel (58.1) end of the stem (58.2) pro trudes
through the gland’s (67) upper side, place a
new threadseal washer (61) over the stem’s
(58.2) upper end. Continue engaging stem
(58.2) until the O-ring (63) is pulled into the
gland (67).
21. Install washer (60) and locking lever (59) onto
stem (58.2).
22. Place handwheel stem (58.2) into a soft-jawed
vise. Position handwheel (58.1) onto stem
(58.2) with holes for pin (66) aligned. Insert
pin (66) and drive through stem (58.2) and
handwheel (58.1) far side. Remove handwheel
assembly (MHWO) from vise.
F. Manual Handwheel Operator:
1. Reference Item Number drawing at end of IOM
for de tails of the man u al handwheel op er a tor
(MHWO) sub-assembly.
2. Place unit (AA) (BA) on a
fl
at work surface
with the handwheel (58) on topside.
3. Ensure all air pressure has been released from
ac tu a tor casing (1). Ensure handwheel (58)
is fully “backed-out” by rotating CCW (viewed
from above); i.e. is as “high” as pos si ble.
4. Remove slotted-head screw (65) securing
handwheel gland (67) to upper casing (1).
5. Place a smooth-jawed wrench onto handwheel
gland (67) and rotate CCW (viewed from
above) to removal of the manual handwheel
operator sub-assembly (MHWO).
6. Place the sub-assembly (MHWO) into a vise,
grasping with leaded jaws on the coarse-
screwed handwheel stem (58.2) near the
base of the handwheel (58.1), oriented to
allow driving-out the rolled pin (66) securing
the handwheel (58.1) to the handwheel stem
(58.2).
7. Drive pin (66) out using a suitable punch and
locking pliers. Set pin (66) aside for reuse. Re-
move handwheel (58.1) from stem (58.2).
8. Rotate locking lever (59) CCW (viewed from
handwheel-end) to removal.
9. Slide washer (60) and threadseal washer
(61) off handwheel stem-end (58.2). Discard
threadseal washer (61).
10. Remove remaining engaged parts (67) (58.2)
from vise. Reorient horizontally in vise along
fl
ats of handwheel gland (67).
11. Place stick punch in drive-pin hole and rotate
handwheel stem (58.2) CW (viewed from hand-
