Loading Connection; Adjustments; Travel Adjustment - Emerson Fisher 667NS2 Instruction Manual

Instruction Manual
D103472X012
4. Place the actuator on top of the valve with the Fisher logo on the same side as the Fisher logo on the bonnet. If the
assembly has a Type III drawing, mount the actuator as shown on that drawing.
5. Coat the remaining threads of the actuator mounting studs (key 101) and the contact faces of the nuts (key 102)
with Nuclear Grade anti-seize lubricant (key 27). Place the washers (key 143) over the studs (key 101) and thread
the nuts (key 102) onto the studs (key 101) and hand tighten. Torque the actuator mounting nuts (key 102) evenly
in a criss­cross pattern to 292 N•m (215 ft•lbf). The torque for the 667NS with side-mounted handwheel is 315
N•m (426ft•lbf). For actuators with yoke spacers (key 209), connect the yoke spacer in the same way as
connecting the actuator yoke.
6. Do not connect the actuator stem to the valve stem at this time. Whenever the actuator is installed on the valve, it
is recommended that you perform the Bench Set Adjustment procedures below, to verify that the actuator is still
adjusted correctly.

Loading Connection

1. Connect the loading pressure piping to the NPT internal connection in the top of the actuator yoke for size 45 and
70 or on the bottom of the diaphragm casing for size 80.
2. For size 70 actuators, insert a 1/4‐inch bushing in the 1/2 NPT internal connection to decrease connection size, if
necessary.
3. Keep the length of tubing or piping as short as possible to avoid transmission lag in the control signal. If an
accessory (such as a volume booster or valve positioner) is used, be sure that the accessory is properly connected to
the actuator. Refer to the accessory instruction manual if necessary.
4. Cycle the actuator several times to check that the valve stem travel is correct and that the travel occurs when the
correct pressure range is applied to the diaphragm.
5. If valve stem travel is incorrect, refer to the Travel Adjustment procedure in the Adjustments section.
6. If the pressure range is incorrect, refer to the Bench Set procedure in the Adjustments section.

Adjustments

Travel Adjustment

WARNING
When moving the actuator stem with diaphragm loading pressure, use caution to keep hands and tools out of the actuator
stem travel path. Personal injury and/or property damage is possible if something is caught between the actuator stem and
other control valve assembly parts.
Make travel adjustments when the motion observed during actuator travel is different from the travel stamped on the
actuator nameplate. If the Mounting the Actuator on the Valve procedure was followed correctly, this adjustment
should not be necessary.
When adjusting travel of a reverse -acting (push-down-to-close) valve/actuator assembly, apply a low supply pressure
to the actuator diaphragm casing. This moves the valve plug off the seat, reducing the chance of damaging the valve
plug or seat during adjustments.
1. Back the stem locknuts away from the stem connector, and slightly loosen the stem connector cap screws.
CAUTION
Do not use wrenches or other tools directly on the valve stem. Damage to the stem surface and subsequent damage to the
valve packing might result.
667NS2 Actuator
March 2022
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