Cashco SCV-S - Manual (Page 3)

3 IOM-SCV-S
SECTION V
1. Maintenance procedures hereinafter are
based upon removal of the control valve unit
from the piping system where installed.
2. Owner should refer to their pro ce dures for re-
mov al, handling and cleaning of non-re us able
parts, i.e. gaskets, diaphragm, etc.
3. Valves supplied from the factory use a light
coat of Emhart Bostic White Food Grade
"NEVER_SEEZ" or equivalent on seals and
threads.
4. Reference Figures 2 through 6 for iden ti fi ca-
tion of item numbers.
5. All item numbers with respect to body as-
sem bly (BA) will be in parenthesis and not
un der scored; i.e. (1). All item numbers with
respect to the actuator assembly (AA) and
positioner will be in parenthesis and un der-
scored; i.e. (3). Reference with respect to
the po si tion er is in double parentheses; i.e.
((AP)).
6. Special care must be exhibited when ro-
tat ing the stem (3,10) of the valve to not
mar that portion of the surface of the stem
where it contacts with the seal o-rings (9).
To rotate the stem (3,10), use the jam nuts (17)
or grasp stem with soft-jawed pliers. NOTE:
When using the jam nuts to rotate the stem,
use the upper jam nut to rotate the stem CW,
and the lower jam nut to rotate the stem CCW,
when viewed from above valve stem.
7. Hereafter, whenever text has the fol low ing
no ta tion, “(Note PA.)”, the fol low ing text is
to be ap plied;
“For ATO-FC reverse action units, connect
a temporary air source to the actuator and
pres sur ize to a level suf fi cient to initiate
travel to ap prox i mate ly mid-stroke.
V. MAINTENANCE
A. General:
8. Hereafter, whenever text has the fol low ing
no ta tion, “(Note RP.)”, the fol low ing text is to
be applied:
“For ATO-FC reverse action units, re lease
all tem po rary air pressure.
B. Separation of Body/Actuator with Std Threaded
Stem:
NOTE: For units with Opt-68 Quick Dis con nect
Stem proceed to Section V.C. See Fig. 2.
1. Secure body (1) into a vise with the actuator
as sem bly (AA) in the upwards orientation.
Place matchmarks between the yoke (3),
bonnet (2), Tri-Clamp
® (4), and body (1) to
assist in fi nal ori en ta tion when the body is
dis as sem bled and/or the actuator removed.
2. Using an overhead hoist, rig the actuator as-
sem bly (AA) for a vertical lift. Remove slack
from rigging.
3. (Note PA.) Rotate yoke nut (8), CCW (viewed
from above) ap prox i mate ly 2 rev o lu tions. Se-
cure the ac tu a tor stem (6). Loose jam nuts
(17) by rotating CW one-at-a-time to base of
stem (3) threads.
4. Fully loosen any accessory devices that are
connected to the stem (3,6) such as accessory
plate ((AP)) for positioner. (Note RP.)
NOTE: To fully disengage actuator stem (6)
from the stem (3) is a two-step pro ce dure.
Be aware of the valve’s stroke length as in di-
cat ed on the name plate (40) before be gin ning
dis en gage ment. During the dis en gage ment,
mea sure the dis tance ex tend ed, and stay at
least 1/8" (3 mm) away from the full stroke
length. Count and record the number of
rev o lu tions for each step in the box below:
SYSTEM UNDER PRESSURE. Prior to per form ing any
body disassembly or removal for maintenance, in spec-
tion or cleaning, isolate the valve body from the system
and relieve all pressure. Failure to do so could result
in personal injury.
WARNING
No. of revolutions to disengage plug/stem from
actuator stem:
Step A. Step B.
TOTAL:
5. For ATO-FC Reverse Action Units:
a. (Note PA.)
b. Step A. Rotate stem (3) CW (viewed from
above) to disengage the ac tu a tor stem (6)