Actuator Mounting; Parts Ordering - Fisher EHD series Instruction Manual

EH Valves NPS 8 through 14
June 2017

Actuator Mounting

The following procedure assumes that the valve and actuator are fully assembled, but with the actuator removed from
the valve. Unless otherwise identified, the parts involved in making up the actuator‐valve stem connection are shown
in figure 3.
CAUTION
Never use a wrench or pliers on the valve plug stem and never turn the valve plug stem while the valve plug assembly is
seated. A damaged stem could cut the packing and allow leakage. Turning the plug while seated could damage the seats
allowing leakage at shutoff.
1. Turn the stem locknuts onto the valve stem.
2. Move the valve plug to the closed position.
3. Place the actuator on the bonnet and secure with the hex nuts (key 26, figure 11). Connect supply pressure to the
actuator.
4. Make sure the actuator stem is fully retracted. With a properly assembled direct‐acting spring‐return actuator,
spring compression forces the actuator stem to the fully retracted position. A double‐acting piston actuator or a
reverse‐acting spring‐return actuator requires air pressure (or a side‐mounted handwheel) to stroke the actuator
stem to the fully retracted position.
5. Extend the actuator stem a distance equal to the travel (as specified on the nameplate).
6. Attach both halves of the stem connector, making sure the connector fully engages both the actuator threads and
valve plug stem threads. Install the cap screws in the stem connector, but tighten them only slightly at this time.
7. Stroke the valve to the fully open position. The travel indicator should show the valve to be wide open. If it does not,
loosen the screws that hold the travel indicator scale, and shift the scale to the required position.
8. Stroke the valve to the closed position. The travel indicator should show the valve to be closed.
9. If travel is not correct, lift the valve plug assembly (key 3, figure 12 or 14) off its seat approximately 6.4 mm (1/4
inch) and screw the valve plug stem into or out of the stem connector as follows. To lengthen travel, turn the valve
plug stem into the stem connector slightly. To shorten travel, turn the valve plug stem out of the stem connector
slightly. (Turning it out too far will limit the stroke.)
10. After adjusting the stem connection so that the actuator will properly stroke the valve plug assembly, tighten the
cap screws in the stem connector, tightening the one opposite the anti‐rotation groove first. Then lock the stem
locknuts against the stem connector.

Parts Ordering

Each valve is assigned a serial number, which can be found on the valve body. This same number also appears on the
actuator nameplate when the valve is shipped from the factory as part of a control valve assembly. Refer to the
number when contacting your
replacement parts.
When ordering replacement parts, also be sure to include the 11‐character part number for each part required from
the following parts list.
WARNING
Use only genuine Fisher replacement parts. Components that are not supplied by Emerson Automation Solutions should
not, under any circumstances, be used in any Fisher valve, because they may void your warranty, might adversely affect the
performance of the valve, and could cause personal injury and property damage.
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Emerson sales office or Local Business Partner for technical assistance or when ordering
Instruction Manual
D100392X012