cashco 964 Installazione Funzionamento e manutenzione - Pagina 6

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5. For ATC-FO: Connect a temporary air supply

hose that has an ad just able airset with 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 with in 1/8" (3 mm) of reaching the

plug/stem (3).

6. With hand lift plug/stem (3) up to touch ac tu a tor

stem (6). Rotate plug/stem (3) CCW (viewed

from above) to en gage with ac tu a tor stem (6).

Use the total number of revs en gage ment

recorded in Step V.B. as the guide to control

engagement of the stems (6) (3). While en-

gag ing, rotate yoke nut (29) 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 (29) 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 indicating washer (26) - to ac tu a tor

stem (6) with stem jam nuts (18).

Ham mer rap yoke nut (29) until tight. (Release

tem po rary air source.)

D. Trim Removal and Re place ment:

1. Secure body (1) assembly (BA) in a vise with

actuator assembly (AA) di rect ed up wards.

Place match marks be tween the body (1) and

the bonnet (2).

2. Secure the actuator assembly (AA) with an

over head support capable of ver ti cal lift.

3. (Note PA.) Loosen all bonnet stud nuts (17)

(four nuts for 1/2" through 1-1/2" sizes; six

nuts for 2" size).

4. Ensure actuator support is "taut"; i.e. hold ing

weight of actuator.

5. Remove all bonnet bolting nuts (17).

6. Lift the actuator assembly (AA), to geth er with

bon net (2) and stem as sem bly (3) vertically

out of the valve body (1). Lay the topworks

assembly down onto a work bench horizontally.

For 1/2" - 1-1/2" sizes, re move the cage (10)

and seat ring (11) from the body (1) cavity.

7. From the top works as sem bly, loosen the stem

jam nuts (18) by rotating CCW (viewed from

plug end) while se cur ing the actuator stem

(6) with soft-jawed pliers.

8. Loosen stem packing (6) by turn ing nuts (15)

CCW to a point just short of dis en gage ment

from the threads.

9. While securing the actuator stem (6) by soft-

jawed pliers, rotate the valve stem as sem bly

(3) CCW (viewed from plug end). Record the

number of rev o lu tions of dis en gage ment in

the box below:

Number of revolutions to disengage plug/stem as-

sembly from actuator stem.

10. Remove packing flange nuts (15) with CCW

ro ta tion.

11. Partially withdraw plug/stem as sem bly (3).

Re move position in di ca ting washer (26), both

jam nuts (18), packing flange (4), pack ing

follower (5), and ac ces so ry plate ((AP)), if

installed.

12. Fully withdraw stem/plug as sem bly (3). For

1/2" through 1-1/2" sizes, cage (10) may have

come loose see Step 6 above.

13. Using a sharp, hooked-end, pick-type tool,

hook and pull the packing rings (6) up and out

of the bonnet's (2) packing bore individually.

Discard old packing (6).

Take extreme care to not mar internal wall surface of the

bonnet (2).

14. Using a sharp pointed tool, remove packing

washer (23) and packing spring (24).

15. Solvent clean all loose parts with suitable

solvent and let dry.

16. For SIZES 1/2" through 1-1/2", inspect

guide bushing (8) in-place, as the bushing

(8) is press fit into the bonnet (2). If worn

badly or "scored":

a. Remove bonnet (2) by removing yoke

nut (29).

b. Hydraulically press guide bushing (8)

"out" of bonnet (2); press "in" new

guide

bushing (8).

c. Reinstall bonnet (2) back through yoke

(3), and secure with yoke nut (29).

CAUTION

IOM-964