Emerson Fisher 1052 - 1052 Spring Compression Adjustment

Instruction Manual
D101322X012
1051 and 1052 Size 33 Actuators
June 2017
10
11. Refer to the table of contents for accessory installation procedures.
Figure 5. Spring Adjustment
W4767
TRAVEL
STOPS
1052 Spring Compression Adjustment
Initial Compression
Key numbers referred to in this procedure are shown in figure 10 unless otherwise specified.
The 1052 nameplate specifies an initial set adjusted into the actuator spring. Initial set is the casing pressure at which
the diaphragm (key 3) and diaphragm rod (key 10) begin to move away from the stop in the upper diaphragm case
(key 1) when the actuator is disengaged from the control valve body or other operated equipment. The initial set was
determined from the service conditions specified when the actuator was ordered, so that when the actuator and valve
are in service, the valve ball or disc seats properly and full travel is obtained with the supply pressure specified on the
order and shown on the nameplate.
Before adjusting spring tension to change initial set, the valve body or other operated equipment must be removed or
otherwise disengaged from the actuator. Refer to the applicable steps given under the appropriate mounting
adaptation in the Actuator Mounting and Changing Actuator Mounting procedure.
To gain access to the spring adjusting screw, either the spring adjuster cover (key 117) or the switch mounting plate
(key 59) must be removed. If externally mounted switches are used, remove them as an assembly by removing the cap
screws (key 75, figure 16) and the switch mounting plate (key 1, figure 16). In order to gain access to the cap screws, it
may be necessary to loosen the hex nuts (key 77, figure 16) and slide the switches away from the actuator housing.
Note that the lower part of the spring adjusting screw (key 74) is notched so that it can be rotated with a screwdriver
or other flat‐bladed tool. To decrease spring compression, rotate the spring adjusting screw to the right (see figure 5).
To increase spring compression, rotate the spring adjusting screw to the left (clockwise when viewed from above).
Adjust the spring so that the diaphragm rod just starts to travel at the initial set pressure specified on the nameplate.
When the desired initial set has been achieved, install the spring adjuster cover or switch mounting plate.