Emerson Fisher SS-264 Instruction Manual page 20

SS-264 Valve
September 2021
1. Open the valve.
CAUTION
Do not over-pressurize the system or allow for a differential pressure greater than 66psi to develop during this procedure
as it could alter the zero positioning of the valve.
Note
There is a linear indicating mark, just above the packing parts, on the drive shaft indicating the sphere-side of the ball.
2. Install a rotary encoder to the shaft or to the top-works of the Bettis actuator to monitor valve rotation.
3. On the Bettis actuator back out the closed travel stop by turning the stop counter-clockwise (CCW) about 5 turns
(refer to figure 13 for location of travel stop). The closed travel stop is located closest to the large air cylinder of the
Bettis actuator.
4. With the valve in the open position, allow water to flow through the valve while limiting the pressure drop across
the valve to about 10-30 psi.
Note
It takes some time for the Bettis actuator and valve assembly to respond to the step inputs of the regulator. The values in the
following procedure are to provide some guidance in finding the seated position. More important than the actual numbers;
however, is the realization of what is trying to be accomplished: the point at which the ball seats properly and the flow begins to
trend towards the shutoff requirement. Refer to the beginning of this section for more background information on this procedure.
If you have any questions, contact your
CAUTION
The following step, if done incorrectly, could severely damage the seal or ball significantly and/or cause undue stress on the
shaft assembly causing damage. Do NOT increase the actuator pressure rapidly.
5. Using a regulator and calibrated gauge capable of supplying 0-100 psig, slowly apply pressure to the Bettis air
cylinder. Monitoring the flow through the valve; when the ball is seated into the seal there will be a step decrease of
flow. The ball should be closed and set into the seal between 44 to 48 psig.
6. To find where this step change occurs (and the 0-degree position), perform the following steps:
a. Once the regulated actuator supply pressure of 42 psig is reached wait 5 minutes then test and observe the leak
rate.
b. If the leak rate is not acceptable, increase the supply pressure by 0.5 psig. Then allow 5 minutes for the system to
stabilize.
c. Test the leak rate again until the step change decreases flow. Record the regulator pressure at which this water
flow step change happened for future reference.
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Emerson sales office for assistance.
Instruction Manual
D103565X012