Emerson Process Management 667 - Manual (Page 12)

Instruction Manual
D100311X012
667 Size 80 and 100 Actuators
May 2011
12
10. Position the upper diaphragm casing (key 1) on the diaphragm (key 3), and align the holes.
Note
When you replace actuator diaphragms in the field, take care to ensure the diaphragm casing cap screws are tightened to the
proper load to prevent leakage, but do not crush the material. Perform the following tightening sequence with a manual torque
wrench for size 80 and 100 actuators.
CAUTION
Do not use lubricant on these cap screws and nuts. Fasteners must be clean and dry.
Overtightening the diaphragm casing cap screws and nuts can damage the diaphragm. Do not exceed the following
maximum torque values for the appropriate diaphragm material: EPDM/Meta-Aramid: 95 N
Sm (70 lbfSft); Nitrile, Silicone,
FKM (fluorocarbon) / Meta-Aramid: 68 N Sm (50 lbfSft).
11. Insert the cap screws (key 13) into the diaphragm casing, and tighten the hex nuts (key 23) in the following
manner. The first four hex nuts tightened should be diametrically opposed and 90 degrees apart. Tighten these four
hex nuts to the initial torque value found in table 3 for the diaphragm material being used.
12. Tighten the remaining hex nuts in a clockwise, crisscross pattern to the initial torque value found in table 3 for the
diaphragm material being used.
13. Repeat this procedure by tightening four hex nuts, diametrically opposed and 90 degrees apart, to the final torque
value that is specified in table 3 for the diaphragm material being used.
14. Tighten the remaining hex nuts in a clockwise, crisscross pattern to the final torque value that is specified in table
3 for the diaphragm material being used.
15. After the last hex nut is tightened, complete another tightening sequence. Tighten in a circular pattern around the
bolt circle to the final torque value that is specified in table 3 for the diaphragm material being used.
16. Once completed, no more tightening is recommended.
17. For size 80 actuators without a manual operator, slide the following parts over the bottom of the stem; yoke
bushing holder (key 250), two split yoke bushings (key 249), and yoke bushing retainer (key 251). Secure into place
with 4 cap screws (key 252). Before inserting the bushing halves, lightly coat with lithium grease (key 237)
lubricant.
18. Mount the actuator on the valve in accordance with the procedures in the Installation section.
Size 100 Actuator Maintenance
For size 100 actuators, refer to figure 5 for part names and locations. Key number locations for Size 100 actuators are
shown in figure 7.
Table 3. Size 80 Casing Cap Screw Torque Values
DIAPHRAGM MATERIAL
INITIAL TORQUE FINAL TORQUE
N Sm (lbfSft) N Sm (lbfSft)
EPDM / Meta-Aramid 41 (30) 82 $13 (60$10)
Nitrile, Silicone, FKM/Meta-Aramid 34 (25) 68 (50)
WARNING
Avoid personal injury or property damage from sudden release of process pressure or bursting of parts. Before performing
any maintenance operations: