Emerson Fisher 3710 Instruction Manual page 17

Instruction Manual
D101728X012
Figure 8. Drive Stud and Roller Bearing Assembly
ROLLER BEARING
(KEY 101)
DRIVE STUD
(KEY 95)
Note
Before performing the next step, position the valve plug stem at the lower end of its travel. Position the actuator stem at the upper
travel stop. Check for sufficient clearance between the actuator stem and the valve stem to allow removing the stem bracket
assembly. If there is insufficient clearance, remove the actuator from the valve.
5. Loosen the stem bracket retainer (key 14) and let it slide down over the valve plug stem. Remove the stem bracket
assembly (key 13).
6. Install the stem bracket assembly (with drive stud and drive stud bracket) on the actuator stem. Align the stem
bracket assembly so that it will be parallel with the back yoke cover. Install the stem bracket retainer and tighten to
68 NSm (50 lbfSft). If the actuator was removed from the valve, install the actuator on the valve. Do not attach the
stem connector at this time.
7. Attach the mounting bearing (key 97) to the mounting plate (key 43) with three hex socket cap screws (key 93).
8. Refer to the actuator instruction manual. Loosen the four screws, and remove the actuator blanking plate.
9. Attach the positioner mounting plate to the actuator yoke as shown in figure 10 with four spacers (keys 61), four
cap screws (key 45) and lock washers (key 92).
10. Loosen the four captive cover screws and remove the positioner cover.
11. Loosen the cam locknut (key 37, figure 31).
12. Attach the positioner to the mounting plate with three hex socket cap screws (key 46). Make sure that the
positioner feedback shaft (key 38, figure 31) rotates freely and is not binding with the mounting bearing, adjust if
necessary.
13. Attach the feedback lever (key 94) to the end of the feedback shaft with the two hex socket cap screws (key 93).
The markings on the feedback lever should be visible when looking toward the back of the positioner. Make sure the
roller bearing (key 101) on the drive stud engages the slot in the feedback lever.
WARNING
An unexpected change in actuator supply pressure while performing the following steps could result in personal injury. Use
lockout procedures to ensure a stable air supply.
14. Perform the Actuator Mounting procedure steps 2 through 8 in the actuator instruction manual to reconnect the
actuator stem and valve stem.
Figure 9. Drive Stud Bracket with Drive Stud and
Roller Bearing Assembly
E‐RING
(KEY 102)
FLAT WASHER
(KEY 1103)
3710 and 3720 Positioners
LOCK
WASHER
(KEY 100)
HEX NUT
(KEY 96)
September 2017
DRIVE STUD BRACKET
(KEY 98)
DRIVE STUD
AND ROLLER BEARING
17