Emerson 657 User Manual
Instruction Manual
D100306X012
Fisherr 657 Diaphragm Actuator
Sizes 30‐70 and 87
657 Actuator (30-70 and 87)
December 2010
Contents
Introduction 1.................................
Scope of Manual 1.............................
Description 2.................................
Specifications 2...............................
Installation 3...................................
Mounting the Actuator on the Valve 5............
Discussion of Bench Set 6.......................
Spring Verification 7...........................
Installing the Stem Connector Assembly 8.........
Deadband Measurement 8......................
Loading Connection 10.........................
Maintenance 10................................
Actuator Maintenance 11.......................
Top‐Mounted Handwheel Assembly 12...........
Side‐Mounted Handwheel for Sizes 34
through 60 Actuators 14.....................
Side‐Mounted Handwheel for Sizes 70
and 87 Actuators 15.........................
Casing‐Mounted Adjustable Travel Stops 17.......
Parts Ordering 19...............................
Parts Kits 19...................................
Kits for Side‐Mounted Handwheels 19.............
Kits for Top‐Mounted Handwheels 19.............
Parts List 21...................................
Actuator Assembly (figures 6, 7, or 8) 21..........
Top‐Mounted Handwheel (figures 9 or 10) 22......
Side‐Mounted Handwheel (figure 11 or 13) 22......
Figure 1. Fisher 657 or 657‐4 Actuator Mounted
on an easy‐e™ Valve
W2174‐2
Casing‐Mounted Adjustable Up Travel Stops
(figures 14 or 15) 26.........................
Casing‐Mounted Adjustable Down Travel Stops
(figure 16) 27..............................
Introduction
Scope of Manual
This instruction manual provides information on installation, adjustment, maintenance, and parts ordering for the
Fisher 657 actuator in sizes 30 through 70 and size 87. The 657‐4 actuator in sizes 70 and 87 is also covered. Refer to
separate instruction manuals for information about the valve positioner and other accessories used with these
actuators.
www.Fisher.com
657 Actuator (30-70 and 87)
December 2010
Instruction Manual
D100306X012
Do not install, operate, or maintain a 657 actuator without being fully trained and qualified in valve, actuator, and
accessory installation, operation, and maintenance. To avoid personal injury or property damage, it is important to
carefully read, understand, and follow all the contents of this manual, including all safety cautions and warnings. If you
have any questions about these instructions, contact your Emerson Process Management sales office before
proceeding.
Table 1. Specifications
ACTUATOR SIZE
(1)
(3)
(3)
87
76
(1)
(3)
(3)
3
(4)
(2)
(4)
(4)(5)
(1)
2
cm
2
Inch
mm 54 54 71 71 71 90 90 90 127
Inches 2‐1/8 2‐1/8 2‐13/16 2‐13/16 2‐13/16 3‐9/16 3‐9/16 3‐9/16 5
mm 9.5 9.5 12.7 12.7 12.7 19.1 19.1 19.1 25.4
Inches 3/8 3/8 1/2 1/2 1/2 3/4 3/4 3/4 1
N 10230 10230 12010 25131 33582 25131 30246 39142 39142
Lb 2300 2300 2700 5650 7550 5650 6800 8800 8800
mm 19 29 38 51 51 51 51 76
Inches 0.75 1.125 1.5 2 2 2 2 3
Bar 8.6 4.5 4.5 3.4 2.8 3.4 2.8 3.8 3.8
Psig 125 65 65 50 40 50 40 55 55
Bar 9.6 5.2 5.2 4.1 3.4 4.1 3.4 4.5 4.5
Psig 140 75 75 60 50 60 50 65 65
_C Nitrile Elastomers: -40 to 82_C, Silicone Elastomers: -54 to 149_C, Fluorocarbons: -18 to 149_C
_F Nitrile Elastomers: -40 to 180_F, Silicone Elastomers: -65 to 300_F, Fluorocarbons: 0 to 300_F
1/4 NPT X X X X X X X ‐ ‐ ‐ ‐ ‐ ‐
1/2 NPT ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ X X
kg 16 22 23 37 49 42 53 107 116
Lb 36 48 51 82 107 92 116 235 255
30 34 40 45 46 50 60 70
297 445 445 677 1006 677 1006 1419 1419
46 69 69 105 156 105 156 220 220
SPECIFICATION
Nominal Effective Area
Yoke Boss Diameters
Acceptable Valve
Stem Diameters
Maximum Allowable
Output Thrust
Maximum Travel
Maximum Casing
Pressure for
Actuator Sizing
Maximum Diaphragm
Casing Pressure
Material Temperature
Capabilities
Pressure Connections
(internal)
Approximate Weights
1. These values also apply to the 657‐4 actuator construction.
2. Actuator travel may be less than the value listed after connecting the actuator to the valve.
3. Maximum travel for 657‐4 is 102 mm (4 inches).
4. Normal operating diaphragm pressure must not exceed maximum diaphragm casing pressure and must not produce a force on the actuator stem greater than the maximum allowable out
put thrust or the maximum allowable valve stem load. Contact your Emerson Process Management sales office with questions concerning maximum allowable valve stem load.
5. This maximum casing pressure is not to be used for normal operating pressure. Its purpose is to allow for typical regulator supply settings and/or relief valve tolerances.
Description
The 657 actuator (figure 1) and the 657‐4 actuator are direct‐acting, spring‐opposed diaphragm actuators. They
provide automatic operation of control valve body assemblies. The 657 actuator offers 76 mm (3 inches) maximum
actuator travel. The 657‐4 actuator provides 102 mm (4 inches) maximum actuator travel. Both actuators position the
valve plug in response to varying pneumatic loading pressure on the actuator diaphragm. Figure 2 shows the
operation of these actuators.
A 657 or 657‐4 actuator can be equipped with either a top‐mounted or a side‐mounted handwheel assembly. A
top‐mounted handwheel assembly is used as an adjustable up travel stop to limit actuator travel in the up direction
(see figure 2). A side‐mounted handwheel assembly is usually used as an auxiliary manual actuator. Adjustable
casing‐mounted up or down travel stops are also available for this actuator.
2
Instruction Manual
D100306X012
Note
If repeated or daily manual operation is expected, the actuator should be equipped with a side‐mounted handwheel rather than a
casing‐mounted travel stop or top‐mounted handwheel.
The side‐mounted handwheel is designed for more frequent use as a manual operator.
657 Actuator (30-70 and 87)
December 2010
Figure 2. Schematic of Fisher 657 and 657‐4 Actuators
AIR PUSHES
STEM DOWN
SPRING LIFTS
STEM UP
STEM
AF3833‐A
A0792‐2
Specifications
Refer to table 1 for Specifications of the 657 and 657‐4 actuators. See the actuator nameplate for specific information
about your actuator.
Installation
Key number locations are shown in figures 6, 7, and 8, unless otherwise indicated. Also, refer to figure 3 for location of
parts.
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.
3
657 Actuator (30-70 and 87)
December 2010
Figure 3. Actuator Mounting Components for Size 30 through 70 Actuators
NPT INTERNAL CONNECTION
DIAPHRAGM CASING
DIAPHRAGM AND STEM
SHOWN IN UP POSITION
DIAPHRAGM PLATE
LOWER DIAPHRAGM CASING
ACTUATOR SPRING
ACTUATOR STEM
SPRING SEAT
SPRING ADJUSTOR
STEM CONNECTOR
YOKE
TRAVEL INDICATOR DISK
INDICATOR SCALE
Instruction Manual
D100306X012
W0363-1
VALVE STEM
YOKE LOCK NUT
YOKE BOSS DIAMETER
BONNET
TYPICAL VALVE
(REFER TO VALVE MANUAL)
W6199-1
MATCH LINE
FOR ACTUATOR
CAUTION
To avoid parts damage, do not use an operating pressure that exceeds the Maximum Diaphragm Casing Pressure (table 1)
or produces a force on the actuator stem greater than the Maximum Allowable Output Thrust (table 1) or the maximum
allowable valve stem load. (Contact your Emerson Process Management sales office with questions concerning maximum
allowable valve stem load.)
D Valve/Actuator Assembly: If the actuator and valve are shipped together as a control valve assembly, it has been
adjusted at the factory, and may be installed in the pipeline. After installing the valve in the pipeline, refer to the
Loading Connection procedures.
4
Instruction Manual
D100306X012
Figure 4. Bench Set Adjustment
657 Actuator (30-70 and 87)
December 2010
SPRING ADJUSTER
LOWER BENCH SET
LOADING PRESSURE
UPPER BENCH SET
PRESSURE MARK
NOTES:
1
FIRST MOVEMENT OF ACTUATOR STEM IS DETECTED.
2
3
4
ON THE TRAVEL INDICATOR SCALE.
40A8715-B
B2426
THE LOWER PSIG LOADING PRESSURE (MARKED ON NAMEPLATE) WHERE THE
THE UPPER PSIG LOADING PRESSURE EXTENDS ACTUATOR STEM.
MARK THIS POINT WITH TAPE OR A MARKER.
MEASURE DISTANCE OF TRAVEL. IT SHOULD EQUAL THE TRAVEL SPAN SHOWN
1
3
VALVE
STEM
RATED VALVE
TRAVEL MEASURE
4
MARK
VALVE
3
STEM HERE
ACTUATOR STEM
2
UPPER BENCH SET
LOADING PRESSURE
D Actuator Mounting: If the actuator is shipped separately or the actuator has been removed from the valve, it is
necessary to mount the actuator on the valve before placing the valve in the pipeline. Refer to the actuator
mounting procedures before placing the valve in service. You may perform the Bench Set Spring Adjustment
procedures in this section to confirm that the adjustment has not changed since it was shipped from the factory.
D Positioner: If a positioner is installed, or is to be installed on the actuator, refer to the positioner instruction manual
for installation. During the adjustment procedures, it will be necessary to provide a temporary loading pressure to
the actuator diaphragm.
Mounting the Actuator on the Valve
The 657 actuator spring loading pushes the actuator stem up towards the actuator diaphragm (see figure 2). This
spring action moves the stem away from the valve while installing the actuator.
CAUTION
If the valve stem is allowed to remain in the up position (towards the actuator) during mounting, it can interfere with the
actuator mounting, possibly damage valve stem threads or bend the valve stem. Be sure the valve stem is pushed down
(into the valve body), away from the actuator while mounting.
Provide a temporary method of applying diaphragm loading pressure to the diaphragm to extend the actuator stem
during bench set spring adjustments.
5
657 Actuator (30-70 and 87)
December 2010
Instruction Manual
D100306X012
1. Provide a vise or some other method of supporting the valve and the weight of the actuator during assembly. For
direct or reverse acting valves, push the valve stem down away from the actuator while mounting the actuator.
2. Screw the stem locknuts all the way onto the valve stem. With the concave side of the travel indicator disk (key 14)
facing the valve, install the travel indicator disk on the valve stem. (Note: The travel indicator disk is not used with
size 87 actuators.)
3. Lift or hoist the actuator onto the valve bonnet:
a. For size 87 actuators, insert the cap screws and tighten the hex nuts, securing the actuator to the bonnet.
b. For all other size actuators, screw the yoke locknut onto the valve bonnet and tighten the locknut. (Note: On
small size actuators, it may be necessary to remove the indicator disk and re‐install it while lowering the actuator
on to the valve because the disk will not go through the actuator yoke opening.)
4. Do not connect the actuator stem to the valve stem at this time. Whenever the actuator is installed on the valve, it
is recommended to perform the Bench Set Spring Adjustment procedure to verify that the actuator is still adjusted
correctly.
Discussion of Bench Set
The bench set pressure range is used to adjust the initial compression of the actuator spring with the valve‐actuator
assembly “on the bench.” The correct initial compression is important for the proper functioning of the valve‐actuator
assembly when it is put into service and the proper actuator diaphragm operating pressure is applied.
The bench set range is established with the assumption that there is no packing friction. When attempting to adjust
the spring in the field, it is very difficult to ensure that there is no friction being applied by “loose” packing.
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).
If you are attempting to adjust the bench set range after the actuator is connected to the valve and the packing
tightened, you must take friction into account. Make the spring adjustment such that full actuator travel occurs at the
bench set range (a) plus the friction force divided by the effective diaphragm area with increasing diaphragm pressure
or (b) minus the friction force divided by the effective diaphragm area with decreasing diaphragm pressure.
For an assembled valve‐actuator assembly, the valve friction may be determined by following the procedure described
below:
1. Install a pressure gauge in the actuator loading pressure line that connects to the actuator diaphragm casing.
Note
Steps 2 and 4 require that you read and record the pressure shown on the pressure gauge.
2. Increase the actuator diaphragm pressure and read the diaphragm pressure as the actuator reaches its mid‐travel
position.
3. Increase the actuator diaphragm pressure until the actuator is at a travel position greater than its mid‐travel
position.
4. Decrease the actuator diaphragm pressure and read the diaphragm pressure as the actuator reaches its mid‐travel
position.
The difference between the two diaphragm pressure readings is the change in the diaphragm pressure required to
overcome the friction forces in the two directions of travel.
6
Instruction Manual
D100306X012
5. Calculate the actual friction force:
657 Actuator (30-70 and 87)
December 2010
Friction
Force, = 0.5
pounds
Difference
in pressure
readings, psig
Effective
diaphragm area,
inches
2
Refer to table 1 for the effective diaphragm area.
When determining valve friction, you can make diaphragm pressure readings at a travel position other than mid‐travel
if you desire. If you take readings at zero or at the full travel position, take extra care to ensure that the readings are
taken when the travel just begins or just stops at the position selected.
It is difficult to rotate the spring adjustor (key 12, figure 6, 7, and 8) when the full actuator loading pressure is applied
to the actuator. Release the actuator loading pressure before adjusting. Then re‐apply loading pressure to check the
adjustment.
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 direct or 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 psig through the
upper bench set pressure marked on the nameplate. Apply loading pressure to the diaphragm.
CAUTION
Stroke the actuator a few times to ensure that the pressure gauge is working correctly, and that the actuator is functioning
properly. To prevent product damage, it is important to be sure that the actuator assembly is not
loading friction on the actuator stem movement.
1. If not already accomplished, provide a temporary means of applying an adjustable loading pressure to the actuator
during bench set adjustments.
2. Set the diaphragm loading pressure at 0 psig. Then, slowly raise the pressure from 0 psig towards the lower bench
set pressure while checking for the first movement of the actuator stem. The actuator stem should show
movement at the lower bench set pressure. If movement occurs before or after the lower pressure is reached,
adjust the spring adjuster (see figure 4) into or out of the yoke until the actuator stem's movement is first detected
at the lower bench set pressure.
3. Be sure the spring adjuster is adjusted to meet the requirements of step 2 above.
4. Apply the upper bench set loading pressure to the diaphragm. This pressure extends the actuator stem down
towards the valve. (Note: the actuator stem may slide over the valve stem as shown in figure 4.) At the end of the
actuator stem, use a marker or a piece of tape to mark the valve stem (see figure 4). (Note: If the actuator stem
does not pass over the valve stem, provide a method to mark this point of stem travel.)
binding or producing any
7
657 Actuator (30-70 and 87)
December 2010
Instruction Manual
D100306X012
5. Slowly decrease the diaphragm loading pressure until the lower bench set pressure is applied. Measure the distance
between the marker or tape on the valve stem to the end of the actuator stem. The distance should match the
travel span shown on the travel indicator scale (key 18). If the span of travel is correct, bench set is complete.
Proceed to the Installing the Stem Connector Assembly subsection.
6. If the travel span is not correct, a wrong or damaged spring has been installed in the actuator. To obtain the correct
spring sizing information, refer to Catalog 14, Actuator Sizing and Sample Calculation sections to determine the
correct spring selection for your application. Or, contact your Emerson Process Management sales office for
assistance. After replacing the spring, repeat the steps above.
Installing the Stem Connector Assembly
When installing the stem connector assembly (key 26), the actuator and valve stem threads should engage the
threads of the stem connector by the distance of the diameter of the stem.
Note
Replacement stem connectors are an assembly of two stem connector halves, cap screws, and a spacer between the connector
halves. Remove the spacer and discard, if present, before clamping the actuator and valve stems together.
1. If necessary, push the valve stem down so that it is touching the seat ring on direct acting valves. For reverse acting
valves, push the stem down to the open position.
If necessary, screw the valve stem locknuts down, away from the connector location. For all actuators except size 87,
ensure that the travel indicator disk (key 14) is located on top of the locknuts.
2. Slowly increase the diaphragm pressure to the upper bench set pressure. This should be the same pressure used in
the bench set steps, and it is marked on the nameplate.
3. Place the stem connector half with the threaded holes, approximately half way between the actuator and valve
stems. Refer to figures 6, 7, and 8 to help locate the connector position.
Be sure that the actuator and valve stem threads are engaging the threads of the stem connector by the distance of
one diameter of the stem.
CAUTION
Incomplete engagement of either the valve stem or actuator stem in the stem connector can result in stripped threads or
improper operation. Be sure that the length of each stem clamped in the stem connector is equal to or greater than one
diameter of that stem. Damage to threads on either stem or in the stem connector can cause the parts to be replaced
prematurely.
4. Install the other half of the stem connector and insert the cap screws and tighten them. If installing a positioner,
also attach the feedback bracket at the same time.
5. Screw the valve stem locknuts up until the indicator disk contacts the bottom of the stem connector, or for size 87
actuators, the stem connector. Do not overtighten the locknuts.
6. Slowly decrease and then increase pressure several times stroking the valve from the lower bench set pressure to
the upper pressure.
Be sure that the valve is in closed position (up or down, depending on valve action). Loosen the screws on the travel
scale, and align it with the travel indicator disk or stem connector. Stroke the valve full travel to ensure that the travel
8
Instruction Manual
D100306X012
657 Actuator (30-70 and 87)
December 2010
matches the valve travel on the travel indicator plate. If valve travel is not correct, repeat the stem connector
procedure.
Figure 5. Typical Valve Response to Deadband
UPPER
BENCH SET
PRESSURE
LOWER
DIAPHRAGM PRESSURE, PSIG
BENCH SET
PRESSURE
15
9
3
0
OPEN
CLOSING
VALVE
RANGE OF
DEADBAND
OPENING
VALVE
MID RANGE
VALVE TRAVEL
CLOSED
1.0
0.6
1
DIAPHRAGM PRESSURE, BAR
0.2
UPPER
BENCH SET
PRESSURE
LOWER
DIAPHRAGM PRESSURE, PSIG
BENCH SET
PRESSURE
15
9
3
0
CLOSED
OPENING
VALVE
RANGE OF
DEADBAND
CLOSING
VALVE
MID RANGE
VALVE TRAVEL
OPEN
1.0
0.6
1
DIAPHRAGM PRESSURE, BAR
0.2
DIRECT ACTING VALVE REVERSE ACTING VALVE
NOTE:
1
A6763‐2
DEADBAND IS CAUSED BY FRICTION.
Note
For push‐down‐to‐close valves, the valve plug seat is the limit for downward travel and the actuator up‐stop is the limit for upward
(away from the valve) movement. For push‐down‐to‐open valves, the actuator down stop is the limit for downward movement,
and the valve seat is the limit for upward (away from the valve) movement.
Deadband Measurement
Deadband is caused by packing friction, unbalanced forces, and other factors in the control valve assembly. Deadband
is the range a measured signal can vary without initiating a response from the actuator (see figure 5). Each actuator
spring has a fixed spring rate (force). You have verified that the right spring was installed in the actuator by completing
the Bench Set Spring Adjustment steps.
Deadband is one factor that affects the control valve assembly operation during automatic loop control. The control
loop tolerance for deadband varies widely depending on the loop response. Some common symptoms of the
deadband being too wide are no movement, a “jump” movement, or oscillating movements of the actuator during
automatic loop control. The following steps are provided to determine the span of deadband. The percent of
deadband is helpful in troubleshooting problems with the process control loop.
1. Start at a pressure near the lower bench set pressure, slowly increase pressure until the valve is approximately at
mid‐travel. Note this pressure reading.
2. Slowly decrease pressure until movement of the valve stem is detected, and note this pressure.
3. The difference between these two pressures is deadband, in psi.
4. Calculate the percent of deadband by:
Deadband, psi
Deadband = —————————————— = nn%
Bench Set Span, psi
9
Loading...