Emerson Process Management 3024C - Manual (Page 6)

3024C Actuator
Instruction Manual
Form 5760
March 2007
6
Figure 4. Actuator Mounting Components for Assembly
with a Valve
W8484-1
dimensions. Key numbers referenced in the
following steps are shown in figures 8 and 9.
1. Provide a temporary method of applying
diaphragm air loading pressure to the diaphragm to
move the actuator stem during adjustments.
2. Provide a vice or some other method of
supporting the valve and the weight of the actuator
during assembly.
3. Push the valve stem down until the valve plug is
fully closed.
4. Screw the two stem locknuts (key 52) to the lower
end of the valve stem thread.
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
parts of the valve assembly.
Perform one of the following procedures as
appropriate:
For a Type 3024C Air-To-Close Actuator
with a Push-Down-to-Close Valve:
a. Carefully place the actuator on the valve so
that the yoke boss fits over the valve bonnet.
b. Screw the yoke lock nut onto the bonnet and
tighten.
c. Lift the valve plug off the seat by the correct
valve travel for the valve. This is stated on the
nameplate or in table 1.
d. Place the stem connector half (key 50)
approximately halfway between the actuator and
valve stems but observing the F dimension in
table 5 so that any positioner lever (if fitted) is
horizontal at mid-travel. Be sure that the actuator
and valve stem threads are engaging the threads
of the stem connector by at least the distance of
one diameter of the stem.
CAUTION
Be sure that the length of the actuator
stem and the valve stem in the
connector (key 50) is equal to or
greater than the diameter of that stem.
Incomplete engagement of either the
valve or actuator stem in the stem
connector can result in stripped
threads or improper operation.
In the following procedure do not
rotate the valve plug while it is seated.
This may damage the seating surface
and cause excessive leakage. While
making adjustments, use tools
carefully to avoid damaging the valve
stem. A damaged stem could cut the
packing and allow leakage through the
packing box.
e. Install the other half of the stem connector and
insert the socket screws and nuts and tighten
them.
f. Screw the two stem locknuts (key 52) up the
valve stem to the stem connector and tighten. Do
not over tighten.