Spring Verification - Emerson Fisher 657 Instruction Manual

657 Actuator (30/30i-70/70i and 87)
June 2018
Accurate adjustment to the bench set range can be made during the actuator mounting process by making the
adjustment before the actuator is connected to the valve (see the Spring Verification procedure).
Figure 4. Bench Set Adjustment
SPRING ADJUSTER
LOWER BENCH SET
LOADING PRESSURE
UPPER BENCH SET
PRESSURE MARK
3
VALVE
STEM
NOTES:
THE LOWER PSIG LOADING PRESSURE (MARKED ON NAMEPLATE) WHERE THE FIRST MOVEMENT OF
1
ACTUATOR STEM IS DETECTED.
2 THE UPPER PSIG LOADING PRESSURE EXTENDS ACTUATOR STEM.
MARK THIS POINT WITH TAPE OR A MARKER.
3
4 MEASURE DISTANCE OF TRAVEL. IT SHOULD EQUAL THE TRAVEL SPAN SHOWN ON THE NAMEPLATE.
40A8715-B
B2426

Spring Verification

Ensure that the actuator stem is at the top of its travel as shown in figure 4 and not connected to the valve. (Note:
Some spring compression is required to move the diaphragm to the top of its travel.) The steps provided are the same
for push-down-to-close (direct acting) or push-down-to-open (reverse acting) valves.
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 control valve assembly parts.
Also, provide a certified pressure gauge suitable to accurately read the diaphragm pressure from 0 through 0.3 bar (5
psig) above the upper operating range pressure marked on the nameplate. Apply loading pressure to the diaphragm.
6
1
4
MARK
VALVE
STEM HERE
RATED VALVE
TRAVEL MEASURE
3
Instruction Manual
D100306X012
ACTUATOR STEM
2 UPPER BENCH SET
LOADING PRESSURE