Fisher 655 - Manual (Page 11)

655 and 655R Actuators
Instruction Manual
Form 1292
July 2007
11
tightened to the proper load to prevent
leakage, but not crush the material.
Perform the following tightening
sequence with a manual torque
wrench.
CAUTION
Over-tightening the diaphragm cap
screws (key 19) can damage the
diaphragm. Do not exceed 27 N
Sm (20
lbf
Sft) torque.
Note
Do not use lubricant on these bolts
and nuts. Fasteners must be clean and
dry.
6. Install the upper diaphragm casing (key 1), and
install the cap screws (key 19). Tighten in the
following manner.
7. The first four bolts tightened should be
diametrically opposed and 90 degrees apart. Tighten
these four bolts to 13 N
Sm (10 lbfSft).
8. Tighten the remaining bolts in a clockwise,
criss-cross pattern to 13 N
Sm (10 lbfSft).
9. Repeat this procedure by tightening four bolts,
diametrically opposed and 90 degrees apart, to a
torque of 27 N
Sm (20 lbfSft).
10. Tighten the remaining bolts in a clockwise,
criss-cross pattern to 27 N
Sm (20 lbfSft).
11. After the last bolt is tightened to 27 N
Sm
(20 lbf
Sft), all of the bolts should be tightened again
to 27 N Sm (20 lbfSft) in a circular pattern around the
bolt circle.
12. Once completed, no more tightening is
recommended. Proceed to step 21.
13. For size 3B through 46 actuators, set the
upper diaphragm casing (key 1, figure 4) and
handwheel assembly onto the actuator body, and
secure it with the cap screws and hex nuts (keys 19
and 20, figure 4).
Note
When you replace actuator
diaphragms in the field, take care to
ensure the diaphragm 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.
CAUTION
Over-tightening the diaphragm cap
screws and nuts (keys 19 and 20) can
damage the diaphragm. Do not exceed
27 N
Sm (20 lbfSft) torque.
Note
Do not use lubricant on these bolts
and nuts. Fasteners must be clean and
dry.
14. Install the upper diaphragm casing (key 1), and
install the cap screws and nuts (keys 19 and 20).
Tighten in the following manner.
15. The first four bolts tightened should be
diametrically opposed and 90 degrees apart. Tighten
these four bolts to 13 N
Sm (10 lbfSft).
16. Tighten the remaining bolts in a clockwise,
criss-cross pattern to 13 N
Sm (10 lbfSft).
17. Repeat this procedure by tightening four bolts,
diametrically opposed and 90 degrees apart, to a
torque of 27 N
Sm (20 lbfSft).
18. Tighten the remaining bolts in a clockwise,
criss-cross pattern to 27 N
Sm (20 lbfSft).
19. After the last bolt is tightened to 27 N
Sm
(20 lbf
Sft), all of the bolts should be tightened again
to 27 N Sm (20 lbfSft) in a circular pattern around the
bolt circle.
20. Once completed, no more tightening is
recommended.
21. Connect the pressure control line to the
top-mounted handwheel assembly by following the
procedures outlined in the Loading Connections
portion of the Installation section.
22. To start up and adjust the actuator, follow the
procedures outlined in the Startup section of this
instruction manual.