Cashco SAP - Manual (Page 4)

IOM-SAP 4
D. To replace the seat:
For 3/4" - 1" Sizes:
1. Return to Section VII.B. & C. steps 4 thru 7.
2. Remove seal retainer (37) from plug shoulder.
3. Evenly loosen the cage cap screws (18) CCW
in single revolution increments. The reg u la tor
con tains a return spring (22); the cage should
rise as the cage cap screws are backed out
evenly. Using hand pressure apply downward
force to the top of the cage to pre vent the cage
from pop ping up as the last threads of the
cage cap screws are disengaged. Remove
washers (17).
4. Remove the cage and static seal (15) from
the body. NOTE: Seat (21) maybe stuck to
the bottom of the cage as cage is removed.
If not, remove seat from body cavity.
5. Check the seating surface of the plug for
wear. Examine for signs of leakage. If seat
ring or plug show signs of signifi cant leakage,
determine if op er at ing con di tions - pres sure,
pressure drop, or temperature ex ceed ddesign
lim its. Replace as necessary.
6. Remove spring (22) from within the body (23).
7. Remove seal (28) from body fl ange groove.
8. Clean all metal parts to be reused according
to owner's procedures. NOTE: Regulators are
originally supplied with a level of clean li ness
equal to Cashco cleaning standard #S-1662.
Contact factory for details. Go to Step E.
For 2" Size:
1. Return to Section VII.B. & C. steps 4 thru 7.
2. Lift clamp ring (42) up to remove. Not neces-
sary to remove dowell pin (43).
3. Remove seal retainer (37) from plug shoulder.
NOTE: Flat surface of retainer touches guide
bearing.
4. Remove cage (19) and static seal (15) from
the body. NOTE: Seat (21) maybe stuck to
the bottom of the cage as cage is removed.
If not, remove seat from body cavity.
5. Check the seating surface of the plug for
10. Thread nut (40) on to plug threads and tighten:
Torque 120-130 ft. lbs.
11. Place new loading chamber seal (28) in recess
in the body fl ange face. Set loading chamber on
top of body. Align matchmarks from step B.3.
and insert nuts and bolts (11 & 12). Tighten
bolting equally in a star pattern - Torque to
35-40 ft. lbs.
For 3" & 4" Sizes:
4. Place hands around O.D. of the cage (19) and
lift the complete guide bearing and plug sub-
assembly out of the body. Secure the lower
part of the valve plug (20) in a bench vise;
grasp in "smooth jaws" directly under plug's
seating disc portion on hub "fl ats" provided.
Do not hold on the ma chined sur face in the
plug's spin dle area.
5. Use a wrench to rotate cap screw (40) CCW
and remove.
6. Lift retainer (36) up and over threaded end of
plug (20). Remove seal (35) and o-ring (41).
7. Using hands grasp the guide bearing (13) and
lift upwards to remove. Slide dynamic seal (27)
off end of guide bearing and replace with new
seal. Ensure seal's u-cup is oriented with the
center-open-down wards as shown in Fig ure
1, as the u-cup seal de pends upon inlet pres-
sure to activate prop er seal ing ac tion.
8. Carefully remove o-ring (39) from shoulder of
plug and replace with new o-ring.
9. Place a new u-cup seal (35) with the center-
open-upwards into the recess at the top of the
guide bearing. Reposition the bearing guide
(13) over end of plug and carefully slide it
down into the cage.
10. Place the seal retainer (36) on top of the guide
bearing. Engage cap screw (40) tight onto
the guide bearing. Torque to 180 - 200 ft. lbs.
11. Place new loading chamber seal (28) in recess
in the body fl ange face. Place new o-ring (41)
in groove in top of guide bearing. Set loading
chamber on top of body. Align matchmarks
from step B.3. and insert nuts and bolts (11 &
12). Tighten bolting equally in a star pattern.
Torque to 35 - 40 ft. lbs.