Instruction Manual
D100306X012
657 Actuator (30/30i-70/70i and 87)
June 2018
4
CAUTION
To avoid parts damage, do not use an operating pressure that exceeds the Maximum Diaphragm Casing Pressure (table 1)
or produces a force on the actuator stem greater than the Maximum Allowable Output Thrust (table 1) or the maximum
allowable valve stem load. (Contact your
or Local Business Partner with questions concerning
maximum allowable valve stem load.)
D
Valve/Actuator Assembly:
If the actuator and valve are shipped together as a control valve assembly, it has been
adjusted at the factory, and may be installed in the pipeline. After installing the valve in the pipeline, refer to the
Loading Connection procedures.
D
Actuator Mounting:
If the actuator is shipped separately or the actuator has been removed from the valve, the
actuator should be mounted to the valve before placing the valve in the pipeline when practical. In the case of
needing to place a weld-end body in-line, the trim will be removed from the body during the welding process. When
completed and reassembled, the actuator should then be mounted to the welded in valve assembly. Refer to the
actuator mounting procedures before placing the valve in service. You may perform the Bench Set Spring
Adjustment procedures in this section to confirm the adjustment has not changed since it was shipped from the
factory.
D
Positioner:
If a positioner is installed, or is to be installed on the actuator, refer to the positioner instruction manual
for installation. During the adjustment procedures, it will be necessary to provide a temporary loading pressure to
the actuator diaphragm.
Mounting the Actuator on the Valve
The 657 actuator spring loading pushes the actuator stem up towards the actuator diaphragm (see figure 2). This
spring action moves the stem away from the valve while installing the actuator.
CAUTION
If the valve stem is allowed to remain in the up position (towards the actuator) during mounting, it can interfere with the
actuator mounting, possibly damage valve stem threads or bend the valve stem. Be sure the valve stem is pushed down
(into the valve body), away from the actuator while mounting.
Provide a temporary method of applying diaphragm loading pressure to the diaphragm to extend the actuator stem
during bench set spring adjustments.
1. Provide a vise or some other method of supporting the valve and the weight of the actuator during assembly. For
direct or reverse acting valves, push the valve stem down away from the actuator while mounting the actuator.
2. Screw the stem locknuts all the way onto the valve stem. With the concave side of the travel indicator disk (key 14)
facing the valve, install the travel indicator disk on the valve stem.
(
Note:
The travel indicator disk is not used with
size 87 actuators.)
3. Lift or hoist the actuator onto the valve bonnet:
a.
For size 87 actuators,
insert the cap screws and tighten the hex nuts, securing the actuator to the bonnet.
b.
For all other size actuators,
screw the yoke locknut onto the valve bonnet and tighten the locknut.
(
Note:
On
small size actuators, it may be necessary to remove the indicator disk and re‐install it while lowering the actuator
on to the valve because the disk will not go through the actuator yoke opening.)
