Fisher 667 Instruction Manual page 15

8. The lower sleeve (key 123) has a milled groove in
one end. Coat the sleeve threads with lubricant (key
239 or equivalent), slide the end of the lower sleeve
with the groove into the bearing retainer flange, turn
the handwheel, and feed the sleeve through the worm
gear so that the slot in the lower sleeve engages the
key (key 122) in the yoke. Continue turning the hand-
wheel until the lower sleeve protrudes 81 mm (3.19
inches) below the surface of the yoke. The bottom of
the lower sleeve should be even with the bottom of the
extension on the neutral indicator.
9. Pack the thrust bearing (key 128) with lubricant
(key 239) or equivalent. Slide the actuator stem (key
144) and the attached adjusting screw (key 131), pin
(key 130), thrust bearing (key 128), spring seat (key
19), and spring adjuster (key 74) into the yoke. The
lower end of the stem slides through the lower sleeve
(key 123) and the lower sleeve slides into the adjusting
screw (key 131), as shown in figure 15.
10. Position the actuator stem (key 144) against the
valve stem. Clamp both stems between the two halves
of the stem connector (key 31), and be sure the
threads are engaged properly on both stems. The
stem connector should not be closer than 3.2 mm
(0.125 inches) to the lower sleeve when the actuator
stem is in the retracted position. This adjustment will
provide approximately 3.2 mm (0.125 inches) of free
travel of the lower sleeve in either direction for manual
operation. Fasten the halves together with the cap
screws.
11. Put the actuator spring (key 18) in the yoke on the
spring seat (key 19).
12. Coat the O-rings (keys 8 and 9) with lubricant (key
237) or equivalent, and insert them in the seal bushing
(key 7). Slide the seal bushing and O-rings into the
spring case adaptor (key 89).
13. Install the snap ring (key 72).
14. Slide the seal bushing and O-rings (keys 7, 8,
and 9) over the actuator stem (key 144), and position
the spring case adaptor (key 89), lower diaphragm
casing (key 64), and O-ring (key 70) on the yoke.
15. Insert and tighten the cap screws (key 90).
16. Slide the lower diaphragm plate (key 71), the dia-
phragm (key 3) with the patterned side up, the dia-
phragm plate (key 4), the spacer (key 2), and the cap
screw (key 12) on the actuator stem (key 144). Tighten
the cap screw.
17. Put the diaphragm casing (key 1) on the dia-
phragm. Align the holes in the diaphragm (key 3) and
the diaphragm casings (keys 1 and 64).
Type 667 Size 30-76 & 87
When you replace actuator diaphragms
in the field, take care to ensure the dia-
phragm casing bolts are tightened to the
proper load to prevent leakage, but not
crush the material. Perform the following
tightening sequence with a manual
torque wrench for size 30-76 and 87 ac-
tuators.
CAUTION
Over-tightening the diaphragm cap
screws and nuts (keys 13 and 14) can
damage the diaphragm. Do not exceed
27 NSm (20 lbfSft) torque.
Do not use lubricant on these bolts and
nuts. Fasteners must be clean and dry.
18. Install the cap screws and hex nuts (keys 13
and 14) and tighten in the following manner.
19. The first four bolts tightened should be diametri-
cally opposed and 90 degrees apart. Tighten these
four bolts to 13 NSm (10 lbfSft).
20. Tighten the remaining bolts in a clockwise, criss-
cross pattern to 13 NSm (10 lbfSft).
21. Repeat this procedure by tightening four bolts,
diametrically opposed and 90 degrees apart, to a
torque of 27 NSm (20 lbfSft).
22. Tighten the remaining bolts in a clockwise, criss-
cross pattern to 27 NSm (20 lbfSft).
Note
Note
15