Emerson Fisher 667 Instruction Manual page 8

667 Actuator (Size 30/30i - 76/76i and 87)
June 2017
Key numbers are shown in figures 6, 7, 8, 9, and 10.
Note
For 667 actuators installed on push-down-to-close (direct acting) valves with fail-close action, the valve plug seat is the limit for
downward travel and the actuator is the limit for upward (away from the valve) movement.
For 667 actuators installed on push-down-to-open (reverse acting) valves with fail-open action, the actuator down stop is the limit
for downward movement, and the valve seat is the limit for upward (away from the valve) movement.
Ensure the correct Spring Verification procedure is followed for the type of valve on which the 667 actuator is installed.
For Push Down to Close (Direct Acting) Valves
1. If not already accomplished, push the valve stem down away from the actuator to the closed position.
2. Set the diaphragm loading pressure to 0.3 bar (5 psig) over the upper operating range pressure. The travel stop cap
screw (key 12) should be contacting the upper diaphragm casing.
3. Slowly decrease the pressure towards the upper bench set pressure, as indicated on the nameplate, while checking
for the first linear movement of the actuator stem.
Note
Before turning the spring adjuster on size 70/70i, 76/76i, or 87 actuators, assemble the stem connector around the actuator stem
and the anti‐rotating lug on the yoke. Mark the actuator stem as a visual reference to verify that stem rotation does not occur.
Remove the stem connector before rechecking the bench set.
4. If movement occurs before or after the upper bench set pressure is reached, adjust the spring adjuster (see figure
4). Thread the adjuster up or down on the actuator stem until the actuator stem movement is first detected at the
upper bench set pressure. (Note: You may need to lower the loading pressure to reduce spring compression,
allowing the spring adjuster to turn.)
5. Be sure the spring adjuster is adjusted to meet the requirements of step 4 above.
6. Slowly decrease diaphragm loading pressure to the lower bench set pressure, as indicated on the nameplate. This
will extend the actuator stem toward the valve. Mark the end of the actuator stem on a nearby surface using tape or
some other method.
7. Slowly increase the diaphragm loading pressure until the upper bench set pressure is reached. Again, the travel stop
cap screw (key 12) should be against the upper diaphragm casing.
8. Measure the distance between the mark or tape to the end of the actuator stem. This distance should match the
rated travel indicated on the nameplate.
9. If the measured travel matches the nameplate travel, bench set is complete. Proceed to the Installing the Stem
Connector Assembly subsection.
10. If the measured travel is not exact, consider the spring free‐length and spring rate tolerances may produce a
slightly different bench set than specified. Contact your Emerson Automation Solutions sales office for assistance.
For Push Down to Open (Reverse Acting) Valves
1. If not already accomplished, push the valve stem down away from the actuator to the open position. Later, when
installing the connector, pull up the valve stem to the closed position.
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Instruction Manual
D100310X012