Table of Contents
Advertisement
1051 & 1052 F & G Actuators
a. Push-down-to-close—Slowly stroke the
actuator to the down travel stop. Adjust the
turnbuckle (key 57) until the valve is in the closed
position. Lock this adjustment with the left-hand
threaded locknut (key 58). Stroke the actuator to
the mid-travel position, and tighten the locknut
(key 16).
b. Push-down-to-open—Release all pressure
from the diaphragm casing, making sure the
diaphragm is against its up travel stop. Be sure
that the optional handwheel is adjusted to its
topmost position so that the zero position of the
actuator and valve can be reached
simultaneously. Check the valve position. Stroke
the actuator so the turnbuckle (key 57) is
accessible through the access opening. Adjust
the linkage. Release pressure to the actuator,
and check the new adjustment. Continue this
procedure until the valve is in the closed position
when the actuator is resting on its up travel stop.
Stroke the actuator to the mid-travel position, and
tighten the locknut (key 16). Stroke the actuator,
and tighten the left-hand threaded locknut
(key 58).
5. Replace the access plate (key 59).
6. Loosen the self-tapping screws (key 38), adjust
the travel indicator (key 37), and re-tighten the
self-tapping screws.
Type 1052 Spring Adjustment
Initial Setting
The Type 1052 nameplate specifies an initial spring
setting, which is the initial setting adjusted into the
actuator spring. Initial setting is the casing pressure
at which the diaphragm and diaphragm rod begin to
move away from the up travel stop with the
actuator disconnected from the valve. (With the
actuator connected to the valve and pressure
applied to the valve, a higher pressure will be
required to start actuator travel).
The initial setting was selected (based upon the
service conditions specified when the actuator was
ordered) so that, when the actuator and valve are in
service, the valve will seat properly and full travel will
be obtained within a diaphragm casing range of 0 to
1.2, 0 to 2.3, 0 to 2.8, or 0 to 3.8 bar (0 to 18, 0 to
8
33, 0 to 40, or 0 to 55 psig) depending on specific
actuator size and construction.
If the actuator has been disassembled or if the
spring adjustment was changed, and it is desired to
match the initial setting stated on the nameplate,
make sure the rod end bearing (key 17, figure 8 or 9)
has been disconnected from the lever (key 27,
figure 8 or 9). Adjust the spring so that the
diaphragm rod just starts to travel at the spring set
pressure specified on the nameplate.
Be sure the rod end bearing does not hit the lever as
the diaphragm and diaphragm rod move away from
the up travel stop. To adjust the spring, insert a
round rod into one of the holes in the lower bearing
seat (key 73, figure 9). Hole diameter is 9.5 mm (3/8
inch) for size 40 actuators, 15.9 mm (5/8 inch) for
size 60 actuators, and 19.1 mm (3/4 inch) for size 70
actuators. Rotate the bearing seat to move it toward
the casing to increase initial setting or away from the
casing to decrease initial setting (keys 1 and 2,
figure 9).
Stroking Range
The initial spring setting listed on the nameplate has
been determined to be the optimum setting, and it is
not recommended to make spring adjustments that
will cause this value to change or be exceeded. For
push-down-to-open valve action, the initial spring
setting is the maximum allowable to provide the
maximum spring closing force.
CAUTION
Any increase of this setting will
over-stress the spring at full travel and
may shorten the fatigue life of the
spring.
For push-down-to-close valve action, the initial
spring set has been determined to be the optimum
balance between the air-to-close and the
spring-to-open breakout torque.
If the Type 1052 actuator is to be changed from one
valve action to another (i.e., push-down-to-close to
push-down-to-open), first, refer to the table for
key 11 in the Parts List section to determine the
proper initial spring setting; then, adjust the unit
according to the procedures in the Initial Settings
portion of the Type 1052 Spring Adjustment section.
Instruction Manual
Form 5062
May 2008
Advertisement
Table of Contents
