cashco 987 설치, 운영 및 유지보수 매뉴얼 - 페이지 6
{카테고리_이름} cashco 987에 대한 설치, 운영 및 유지보수 매뉴얼을 온라인으로 검색하거나 PDF를 다운로드하세요. cashco 987 15 페이지. Globe-style pneumatic control valve body iom
페이지 인쇄C. Actuator Replacement:
1. Secure body assembly (BA) in a vice with
the valve stem (4) oriented ver ti cal ly. Push
plug/stem (4) down until the plug touches the
seating surface in the body (1).
2. Secure the actuator assembly (AA) from
above. Use matchmarks from B.1. previous
to assist with (BA) and (AA) alignment.
3. This procedure assumes that the bonnet (2)
has been installed to the body (1), with stem
jam nuts (17) on the valve stem (4) .
4. Lower actuator assembly (AA) until the valve
stem (4) penetrates the opening in the yoke
(3). Re po si tion the "dangling parts" - packing
flange (23), yoke nut (15), ac ces so ry plate
((AP)) and in di cat ing washer (16) - over the
body stem (4). Con tin ue to lower the actuator
assembly (AA) until there is ap prox i mate ly
1/4" (6 mm) space between the two stems
(6) (4).
5. For ATC-FO: Connect a temporary air supply
hose that has an ad just able airset and gauge
to the ac tu a tor inlet to allow pres sur iza tion.
Slowly pressurize actuator to bring the
ac tu a tor stem (6) to be with in 1/8" (3 mm) of
contacting the valve stem (4).
6. With hand, lift stem (4) up to touch ac tu a tor
stem (6). Rotate valve stem (4) CCW (viewed
from above) to en gage w/ ac tu a tor stem (6).
Use the total number of revs en gage ment
recorded in Step V.B.4. as the guide to control
engagement of the stems (6) (4).
en gag ing the stems, rotate yoke nut (15) as
able to help stabilize top works, continue to
pres sur ize the ac tu a tor in 2-3 psi (.15-.20 Bar)
in cre ments in an al ter nat ing se quence with
the distance en gaged until the total num ber
of revs engaged is reached.
7. Hand-tighten yoke nut (15) until fully po si tioned
with the yoke (3) sitting on the bonnet (2).
8. Secure "dangling parts" - ac ces so ry plate
((AP)) and indicator washer (16) - to ac tu a tor
stem (6) with stem jam nuts (17).
9. Ham mer rap yoke nut (15) until tight. (Release
tem po rary air source.)
10. Install nuts (21) on studs (20). Use torque
wrench to tighten to 25-30 in-lbs.
6
D. Trim/Packing Removal and Replacement:
NOTE: This Subsection assumes that the ac tu a tor
assembly (AA) has been already re moved
per Sub-section B. previous.
1. Secure (BA) in a vise with the valve stem (4)
pointing up wards.
2. Pull stem (4) upwards. Hold stem (4) up if
nec es sary using soft-jawed locking pli ers.
Loosen four bonnet flange nuts (9) and
remove.
It sometimes occurs that the stem (4) will "stick" within the
bon net (2) and pull out with parts of this step above. DO NOT
ALLOW THE STEM (4) TO DROP and do per son al injury or
damage stem (4)!
3. Carefully wiggle stem (4) side-to-side to break
loose bonnet (2) from body (1). Lift the bon net
(2) directly upwards along with stem (4),bonnet
flange (7) and all the packing components
(10,11). Lay the group of parts on a flat work
surface. Ensure that the bonnet (2) will not
"roll".
4. Remove bonnet flange (7) from bonnet (2).
5. Remove packing follower (11) over threaded
end of stem (4).
6. Push stem (4) threaded-end into bonnet (2)
as far as possible using fingers while holding
bonnet (2) with other hand. Grasp plug-end
While
of plug/stem subassembly (4) and withdraw
from the bonnet (2) and thru the packing rings
(10). Set plug/stem subassembly (4) aside.
7. Place bonnet (2) into a leaded-jaw vise with
packing-end upwards. Using a pick-type tool,
remove the five packing rings (10). Inspect
rings (10) for signs of damage and then discard.
8. Place all bonnet-area removed parts (2,4,7,11)
into a suitable cleaning solvent.
9. Remove bonnet O-ring seal (6) from body (1).
Inspect O-ring (6) for signs of failure to seal,
then discard.
10. If body (1) includes a screwed-in seat ring (3),
use a sufficiently wide piece of 1/4" thick steel
bar to remove the seat ring (3) by ro tat ing seat
ring (3) CCW (viewed from above) to re mov al.
CAUTION
IOM-987