Emerson Process Management 3024C - Manual (Page 11)

3024C Actuator
Instruction Manual
Form 5760
March 2007
11
diaphragm without moving either the upper
diaphragm casing or the diaphragm plate so that
the diaphragm holes line up with those in the
casings.
d. Lift off the upper diaphragm casing and
remove the springs. Tighten the travel stop nut
(key 14 as follows: Sizes 30, 30E, 34, and 34E,
tighten to 36 N
Sm (27 lbfSft); Sizes 40, 40E, 45,
and 45E, tighten to 87 N
Sm 64 lbfSft).
e. Replace the spring as previously.
f. For actuator sizes 40E and 45E with 1.5 and 2
inch travels, a casing spacer is fitted between the
upper and lower diaphragm casings. Place the
casing spacer (key 29) on the diaphragm and
then the gasket (key 30) as shown in figure 13.
For a Type 3024C Air-to-Close Actuator
(figure 8)
a. Position the actuator springs symmetrically on
the spring locator (key 17) as shown in figure 5.
b. For actuator sizes 40E and 45E with 1.5 and 2
inch travels, a casing spacer (key 29) is fitted
between the upper and lower diaphragm casings.
Place the gasket (key 30) on the lower casing
and then the casing spacer (key 29) as shown in
figure 14.
c. Carefully slide the actuator stem with the
assembled parts down through the bushing and
position it so that the springs fit correctly over the
seat bosses on the upper side of the diaphragm
plate (key 13). Rotate the diaphragm (key 11)
without moving the diaphragm plate (key 13) so
that the diaphragm holes line with the lower
diaphragm casing holes.
d. Tighten the travel stop nut (key 14) as follows:
Sizes 30, 30E, 34 and 34E tighten to 36 N
Sm (27
lbf Sft); Sizes 40, 40E, 45 and 45E tighten to 87
N Sm (64 lbfSft).
4. Install the upper diaphragm casing (key 16) so
that the air connection is located directly above the
air connection in the lower diaphragm casing (key 1).
Using the long cap screws (key 21) and hex nuts
(key 20) first, and then the shorter cap-screws
(key 19) and hex nuts (key 20), bolt the two
diaphragm casings together. Fit the safety plastic
hose (key 22) over the exposed thread of the long
cap-screws (key 21).
CAUTION
Over tightening the diaphragm cap
screws and nuts can damage the
diaphragm. Do not exceed the torque
of 13 N
Sm (10 lbfSft) for sizes 30, 30E,
34 and 34E and 17 N Sm ( 12 lbfSft) for
sizes 40, 40E, 45, and 45E.
Note
Be sure to use the long cap screws
(key 21) first, installing them on
opposite sides of the diaphragm
casing. Tighten them evenly, using a
criss-cross pattern to ensure a proper
seal.
5. Mount the actuator on the valve in accordance
with the Installation Procedures.
Changing the Actuator Action
The actuator can be changed from a Type 3024C
Air-to-Open to a 3024C Air-to-Close action or vice
versa. Remove the pressure plate, diaphragm,
O-ring, diaphragm plate, travel stop nut, springs,
spring locator, self tapping screws and vent
assembly (keys 10, 11, 12, 13, 14, 15, 17, 18
and 23) and reinstall them for the appropriate action.
Follow the instructions in the section on Assembly
on page 8.
Side-Mounted Handwheel
A side-mounted handwheel assembly (figure 10) is
usually used as a manual operator. When mounted
on an Air-to-Close Type 3024C actuator, turning the
handwheel clockwise always closes the valve. When
mounted on an Air-to Open actuator, turning the
handwheel clockwise always opens the valve. A
lever (key 101, figure 10) on the handwheel
assembly opens or closes the valve by moving the
valve stem.
Instructions are given below for complete
disassembly and assembly. Perform the
disassembly only as far as is necessary to
accomplish the required maintenance; then begin
the assembly at the appropriate step.
Refer to figure 10 for key numbers.
Disassembly
1. If desired, the handwheel assembly can be
removed from the actuator yoke. To do this, remove