Emerson Process Management 667 - Manual (Page 4)

Instruction Manual
D100311X012
667 Size 80 and 100 Actuators
May 2011
4
Because the actuator has traveled its specified travel, and the diaphragm head is physically stopped from movement,
the force from any additional air pressure is transmitted to the diaphragm and diaphragm casings. The amount of air
pressure that can be added once the actuator has traveled to the stops is limited by the resultant adverse effects that
may occur. Exceeding this limiting factor could result in leakage or casing fatigue due to the deformation of the upper
diaphragm casing.
D Maximum Diaphragm Casing Pressure: If the Maximum Diaphragm Casing Pressure is exceeded, damage to the
diaphragm, diaphragm casing, or actuator might result. For some actuator constructions, the maximum
Diaphragm Casing Pressure is the sum of the upper bench set, noted on the nameplate, added to the Maximum
Excess Diaphragm Pressure. For other actuator sizes, the value is lower, see table 2.
WARNING
To avoid personal injury or parts damage, do not exceed the Maximum Diaphragm Casing Pressure listed in table 2. The
Maximum Diaphragm Casing Pressure must not produce a force on the actuator stem greater than the maximum allowable
actuator output thrust or the maximum allowable stem load.
Installation
WARNING
Always wear protective gloves, clothing, and eyewear when performing any installation operations to avoid personal
injury.
Check with your process or safety engineer for any additional measures that must be taken to protect against process
media.
If installing into an existing application, also refer to the WARNING at the beginning of the Maintenance section in this
instruction manual.
When an actuator and valve are shipped together, the actuator is normally mounted on the valve. Follow the valve
instructions when installing the control valve in the pipeline. If the actuator is shipped separately or if it is necessary to
mount the actuator on the valve, perform the following Actuator Mounting procedures.
For information on mounting valve positioners, refer to the appropriate valve positioner instruction manual.
Actuator Mounting
1. Mount the actuator on the valve bonnet. Insert the cap screws and tighten the hex nuts, securing the actuator to
the bonnet.
2. Screw the valve stem jam nuts (key 69, figures 6 and 7) all the way onto the valve stem threads.
3. Connect an air supply to the lower diaphragm casing connection.
4. For push‐down‐to‐close valves, be sure the valve plug is on its seat. Reduce loading pressure to ensure that the
actuator stem is fully extended. Apply slight loading pressure to retract the stem approximately 3.2 mm (1/8‐inch).
5. For push‐down‐to‐open valves, apply pressure to ensure that the actuator stem is fully retracted. Be sure the valve
plug is on its seat. On large valve sizes, this may require the use of a pry bar inserted through the valve body line