Cashco 2296HF - Manual (Page 4)

4 IOM-2296
V. MAINTENANCE
WARNING
SYSTEM UNDER PRESSURE. Prior to performing
any maintenance, isolate the valve/actuator from the
sys tem and relieve all pressure. Failure to do so could
result in personal injury.
A. General:
1. Maintenance procedures hereinafter are
based upon removal of the valve/actuator
unit from the pipeline where installed.
2. Owner should refer to Owner’s procedures for
re mov al, handling and cleaning of non re us able
parts, i.e. gaskets, suitable sol vents, etc.
3. General service valves supplied from the fac-
tory do not require use of any gasket sealant.
(See below for “oxygen cleaned” valves.)
4. Valves originally supplied in accordance
with Option-55 require special cleaning pro-
ce dures. Refer to Cashco Specifi cation No.
S-1134 for details. When in compliance with
Spec. #S-1134, the valve is suitable for ox y-
gen service. Sealants and lubricants used in
reassembly of a valve unit for use in oxygen
service MUST be suitable for O
2
service.
5. All indicated Item Numbers that are with
re spect to the actuator assembly (AA) are in
parenthesis and underscored; i.e. (20). All
Item Numbers that are with respect to the body
assembly (BA) are not un der scored; i.e. (32).
Reference with respect to the positioner is in
double parentheses; i.e. ((AP)).
6. Special care must be exhibited when ro tat-
ing the plug stem (4) in the body to not mar
that portion of the surface of the stem (4)
where it contacts with the packing (10). To
rotate the stem use the jam nuts (17) or grasp
stem with soft-jawed pliers. NOTE: When using
the jam nuts (17) to rotate the stem (4), use
the upper jam nut to rotate the stem CW, and
the lower jam nut to rotate the stem CCW,
when viewed from above the valve stem.
7. Hereafter, whenever text has the following
notation, "(Note PA.)", the following text is
to be applied:
"For ATO-FC units ONLY, connect a tempo-
rary air source with gauge to the actuator
and pressurize to a level suffi cient to initiate
travel to approximately mid-stroke."
8. Hereafter, whenever text has the following
notation, "(Note RP.)", the following text is
to be applied:
"For ATO-FC units ONLY, release all tem-
porary air pressure."
B. Actuator Removal:
1. Secure the body assembly (BA) in a vise with
the actuator assembly (AA) oriented vertically.
Place matchmarks between the body (1) and
bonnet (2) fl ange, (for 2" size); mark the yoke
(3) to assist in fi nal ori en ta tion when the body
is dis as sem bled and/or the actuator removed.
2. (Note PA.) Using blunt end tool, ham mer rap
the tool to loosen yoke nut (15) turning CCW
(viewed from above) ap prox i mate ly 2 rev o lu-
tions. Secure the ac tu a tor stem (6). Loos en
the stem jam nuts (17) by rotating CW (viewed
from above) one-at-a-time until ro ta tion stops.
3. Fully loosen any accessory de vic es that are
con nect ed to the stem (6) or (4) such as ac ces-
so ry plate ((AP)) for limit switch or po si tion er.
4. Loosen stem packing (10) by turning nuts (21)
CCW 2-3 rev o lu tions. (Note RP.).
NOTE: To fully disengage the actuator stem (6)
from the plug/stem (4) 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:
SECTION V
No. of revolutions to disengage valve stem from
actuator stem:
Step A. ____________ Step B. ___________
TOTAL: ____________