Fisher 657 User Manual

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Instruction Manual
Form 1909 August 2006
657 Size 80 and 100 Actuators
Type 657 Diaphragm Actuators Size 80 and 100
Contents
Introduction 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Scope of Manual 2. . . . . . . . . . . . . . . . . . . . . . . . .
Description 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Specifications 2. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Actuator Mounting 3. . . . . . . . . . . . . . . . . . . . . . . .
Loading Connection 3. . . . . . . . . . . . . . . . . . . . .
Travel 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spring 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Size 80 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Size 100 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Actuator 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Size 80 Disassembly 6. . . . . . . . . . . . . . . . . . . . .
Size 80 Assembly 7. . . . . . . . . . . . . . . . . . . . . . .
Size 100 Disassembly 8. . . . . . . . . . . . . . . . . . . .
Size 100 Assembly 9. . . . . . . . . . . . . . . . . . . . . .
Size 80 Side-Mounted Handwheel 10. . . . . . . . .
Disassembly 10. . . . . . . . . . . . . . . . . . . . . . . . . . .
Assembly 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Size 80 Hydraulic Snubber 11. . . . . . . . . . . . . . . .
Size 80 Top-Mounted Handwheel
(Adjustable Up Travel Stop) 11. . . . . . . . . . . .
Disassembly 11. . . . . . . . . . . . . . . . . . . . . . . . . . .
Assembly 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Size 100 Top-Mounted Handwheel
(Adjustable Up Travel Stop) 12. . . . . . . . . . . .
Disassembly 12. . . . . . . . . . . . . . . . . . . . . . . . . . .
Assembly 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Ordering 13. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts List 13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Note
Neither Emersonr, Emerson Process Managementt, Fisherr, nor any of their affiliated entities assumes responsibility for the selection, use and maintenance of any product. Responsibility for the selection, use, and maintenance of any product remains with the purchaser and end-user.
Figure 1. Sectional view of Type 657 Size 100 Actuator
Figure 2. Schematic Representation of Type 657 Actuator
W0366-1 / IL
AF3833-A A0792-2/IL
AIR PUSHES STEM DOWN
SPRING LIFTS
www.Fisher.com
D100307X012
Instruction Manual
Form 1909
657 Size 80 and 100 Actuators
Table 1. Specifications
SPECIFICATIONS
2
Nominal Effective Diaphragm Area
Yoke Boss Diameters
Acceptable Valve Stem Diameters
Maximum Allowable Output Thrust
Maximum Travel
Maximum Casing Pressure for Actuator
(3)
Sizing
Maximum Diaphragm Casing Pressure
Material Temperature Capabilities
Pressure Connections 1/4 inch NPT female
Approximate Weights Without Handwheel
1. Heavy actuator-to-bonnet bolting.
2. 88,075 N (19,800 lb) for steel construction.
3. Maximum diaphragm casing pressure must not be exceeded and must not produce a force on the actuator stem greater than the maximum allowable actuator output thrust or the maximum allowable valve stem force. (If you have any questions on allowable valve stem force, contact your Emerson Process Management sales office.)
4. 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.
(3)(4)
cm
2
inch
mm 127 127 178
inch 5 5H
mm 25.4 or 31.8 31.8 50.8
inch 1 or 1-1/4 1-1/4 2
N 62,942 200,170
lb 14,150
mm 76 102
inch 3 4
Cast Iron Steel
bar 3.4 4.9 6.9
psig 50 70 100
Cast Iron Steel
bar 4.1 5.5 7.9
psig 60 80 11 5
_C
_F
kg 234 346
lb 515 762
80 100
1761 2902
273 450
ACTUATOR SIZE
(1)
(2)
−40 to 82
−40 to 180
August 2006
45,000
7
Introduction
Scope of Manual
This instruction manual provides information on installation, adjustment, maintenance, and parts ordering for the Type 657 actuator in sizes 80 and
100. Refer to separate instruction manuals for information about other equipment and accessories used with these actuators.
No person may install, operate, or maintain Type 657 actuators without first D being fully trained and qualified in valve, actuator, and accessory installation, operation, and maintenance, and D carefully reading and understanding the contents of this manual. If you have any questions about these instructions, contact your Emerson Process Management sales office before proceeding.
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Description
The Type 657 actuator (figure 1) is a direct-acting, spring-opposed diaphragm actuator used for automatic operation of control valves. The actuator positions the valve plug in response to varying pneumatic loading pressure on the diaphragm. Figure 2 shows the operation of these actuators.
A Type 657 actuator can be furnished with either a top-mounted or side-mounted (size 80 only) handwheel assembly. A top-mounted handwheel assembly is normally used as an adjustable-up travel stop. The size 100 top-mounted handwheel may be used as an auxiliary manual actuator. A side-mounted handwheel assembly is normally used as an auxiliary manual actuator.
Specifications
Refer to table 1 for specifications of the Type 657 actuator. See the actuator nameplate for information about a specific actuator.
Instruction Manual
Form 1909 August 2006
657 Size 80 and 100 Actuators
Installation
WARNING
To avoid personal injury or parts damage, do not exceed the Maximum Diaphragm Casing Pressure listed in table 1. 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.
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 body are shipped together, the actuator is normally mounted on the valve. Follow the valve body 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 Actuator Mounting procedures as described below.
For information on mounting valve positioners, refer to the appropriate valve positioner instruction manual.
Actuator Mounting
1. To permit adjustment of the actuator spring, the size 100 actuator must be installed in a vertical position above the valve body. Mount the actuator on the valve bonnet. Insert the cap screws, and tighten the hex nuts, securing the actuator to the bonnet.
2. Screw valve stem locknuts (key 16, figure 4) all the way onto valve stem thread.
3. Connect an air supply to the diaphragm casing.
4. For push-down-to-close valves, be sure the valve plug is on its seat. Apply pressure to ensure that the
actuator stem is fully extended. Reduce actuator loading pressure to retract the stem approximately
3.2 mm (1/8-inch).
5. For push-down-to-open valves, move valve plug to closed position. On large body sizes, this may require the use of a pry bar inserted through the body line opening. If the body is installed in a pipeline, the bottom flange (if one is used) can be removed and the valve plug pushed to the seat from the bottom opening. Pressure the actuator to move the stem out 3.2 mm (1/8-inch).
WARNING
To avoid personal injury due to the sudden uncontrolled movement of parts, do not loosen the stem connector cap screws when the stem connector has spring or loading pressure force applied to it.
CAUTION
Incomplete engagement of both valve stem and 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 the diameter of that stem.
6. Clamp the actuator and valve plug stems between the two stem connector halves (key 26, figure 4). Insert and tighten the stem connector cap screws.
7. Thread the stem locknuts against the stem connector.
8. Align the travel indicator scale (key 18, figures 4 and 5) to show valve position.
Loading Connection
1. Connect the loading pressure piping to the connection in the top of the diaphragm casing.
2. Remove the 1/4-inch bushing (key 33, figure 4 and key 120, figure 5) to increase connection size, if necessary. The connection can be made with either piping or tubing.
3. Keep the length of tubing or piping as short as possible to avoid transmission lag in the control signal. If an accessory (such as a volume booster or valve positioner) is used, be sure that the accessory
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657 Size 80 and 100 Actuators
Instruction Manual
Form 1909
August 2006
is properly connected to the actuator. Refer to the positioner instruction manual as necessary.
4. Cycle the actuator several times to check that the valve stem travel is correct and that the travel occurs when the correct pressure range is applied to the diaphragm.
5. If valve stem travel is incorrect, refer to the Travel procedure in the Adjustments section.
6. If the pressure range is incorrect, refer to the Spring procedure in the Adjustments section.
Adjustments
Travel
Make travel adjustments when the motion observed during actuator travel is different from the travel stamped on the actuator nameplate. If the Actuator Mounting procedure was followed correctly, this adjustment should not be necessary.
When adjusting travel of a reverse-acting (push-down-to-open) valve, apply a slight pressure on the actuator diaphragm. This moves the valve plug off the seat, reducing the chance of damaging the valve plug or seat during adjustments.
1. Back the stem locknuts away from the stem connector, and slightly loosen the stem connector cap screws.
Spring
Make spring adjustments when the loading pressure range applied to achieve specified travel is not equal to the pressure range stamped on the actuator nameplate. Refer to the Bench Set pressure range on the nameplate when the valve contains no pressure and the packing is loosely inserted in the bonnet. Refer to the Max. Allow. Supply on the nameplate when the valve is controlling the specified pressure drop and the packing is tightened to stop leaks around the stem.
Monitor loading pressure carefully when making adjustments. Do not exceed the pressure specifications of either the loading regulator or the actuator casings.
Each actuator spring has a fixed pressure span. Changing the spring compression shifts the span up or down to make valve travel coincide with the loading pressure range.
Size 80
Remove cover band (key 60, figure 4), insert a rod of approximately 12.7 mm (1/2-inch) diameter into a hole in the adjusting screw (key 12, figure 4), and rotate the adjusting screw with the rod. Rotating the screw from left to right will increase the loading pressure required to start actuator stem travel; opposite rotation will decrease the pressure required to start travel.
Size 100
CAUTION
Do not use wrenches or other tools directly on the valve stem. Damage to the stem surface and subsequent damage to the valve packing may result.
2. Tighten the locknuts together, using a wrench, then screw the valve stem either into the stem connector to lengthen travel or out of the stem connector to shorten travel.
3. Cycle the actuator to check the travel. If actual travel is not equal to the specified travel, adjust and check travel until correct. Tighten the stem connector cap screws when correct travel is obtained.
4. Raise the travel indicator disk by threading the stem locknuts against the stem connector.
4
CAUTION
The actuator must be in the vertical position when adjusting spring to avoid damage to thrust bearing (key 35, figure 5) and to properly position spacers required for adjustment.
Remove the shroud plate (key 107, figure 5), and loosen the jam nut (key 115, figure 5).
For small spring forces, adjustments can be made by rotating the adjusting nut (key 114, figure 5). Clockwise rotation (when viewed from diaphragm casings) of the adjusting nut will increase the loading pressure required to start actuator stem travel, and counterclockwise rotation will decrease the pressure required to start travel. Tighten the jam nut when adjustment is complete.
Instruction Manual
Form 1909 August 2006
B
JAM NUT
ADJUSTING NUT
A0950-1 / IL
Figure 3. Dimension B for Spring Adjustment
SPRING SEAT
LOWER DIAPHRAGM CASING
For high spring forces, it is necessary to use spacers between the lower diaphragm casing and the spring seat to isolate spring force from the adjusting nut.
WARNING
To avoid personal injury from the compressed actuator spring snapping back to its original length, make and use the spacers by following the instructions in the steps below.
657 Size 80 and 100 Actuators
b. If it is desired to increase spring compression, make the spacers approximately 4.8 mm (3/16-inch) shorter than either dimension B plus the amount of adjustment required or dimension B plus valve travel, whichever is less.
3. Whenever the total amount of adjustment required is greater than valve travel, the adjustment must be made in two or more steps, and the amount of adjustment taken in each step must be less than valve travel.
4. Pressure the actuator to attain full travel. Cautiously insert the spacers at equal intervals around the spring seat (key 11, figure 5). The spacers must be seated squarely when in use or they may slip out of position. Keeping hands and tools away from the spring and spring seat, slowly decrease loading pressure until the spring force holds the spacers firmly between the spring seat and lower diaphragm casing (key 5, figure 5).
5. Loosen the jam nut. The adjusting nut can now be rotated clockwise (when viewed from the diaphragm casings) to increase the loading pressure required to start actuator stem travel or counterclockwise to decrease the pressure required to start travel.
6. Pressure the actuator to move the spring seat away from the spacers, and carefully remove the spacers.
7. If the total adjustment required was greater than valve travel, repeat the procedure. It will be necessary to make new spacers using the new dimension B and the remaining adjustment required or valve travel, whichever is less. Tighten the jam nut when adjustment is complete.
To avoid personal injury, keep hands and tools away from the spring and spring seat as instructed in the following procedure.
1. It is recommended that three spacers be made of 3-inch schedule 80 pipe cut to the appropriate length specified in step 2. If other than the recommended material is to be used, be certain that the spacers are capable of withstanding the spring force involved. The spacers must be of equal length with ends cut squarely.
2. Measure dimension B as shown in figure 3. Cut length of spacers as follows:
a. If it is desired to decrease spring compression, make the spacers approximately 4.8 mm (3/16-inch) longer than dimension B.
Maintenance
WARNING
Avoid personal injury or property damage from sudden release of process pressure or bursting of parts. Before performing any maintenance operations:
D Always wear protective gloves, clothing, and eyewear when performing any maintenance operations to avoid personal injury.
D Disconnect any operating lines providing air pressure, electric power, or a control signal to the actuator. Be
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657 Size 80 and 100 Actuators
Instruction Manual
Form 1909
August 2006
sure the actuator cannot suddenly open or close the valve.
D Use bypass valves or completely shut off the process to isolate the valve from process pressure. Relieve process pressure from both sides of the valve. Drain the process media from both sides of the valve.
D Vent the power actuator loading pressure and relieve any actuator spring precompression.
D Use lock-out procedures to be sure that the above measures stay in effect while you work on the equipment.
D The valve packing box may contain process fluids that are pressurized, even when the valve has been removed from the pipeline. Process fluids may spray out under pressure when removing the packing hardware or packing rings, or when loosening the packing box pipe plug.
D Check with your process or safety engineer for any additional measures that must be taken to protect against process media.
The maintenance instructions are divided into four sections: actuator (sizes 80 and 100); side-mounted handwheel assembly (manual operator); hydraulic snubber; and top-mounted handwheel assembly (adjustable-up travel stop).
Size 80 Disassembly
1. Bypass the control valve. Reduce the loading pressure to atmospheric, and remove the tubing or piping from the top of the diaphragm casing (key 1).
WARNING
To avoid personal injury from the precompressed spring force thrusting the upper diaphragm casing (key 1) away from the actuator, relieve spring compression (step 2, below), and carefully remove casing cap screws (key 22) (step 4, below).
2. Remove cover band (key 60). Insert a rod of approximately 12.7 mm (1/2-inch) diameter into a hole in the adjusting screw (key 12), and rotate the adjusting screw from right to left until spring compression is relieved. If the actuator has a handwheel, rotate it counterclockwise, relieving all spring compression.
3. If necessary, the entire actuator may be removed from the valve body by unscrewing two cap screws from stem connector (key 26) and removing actuator-to-bonnet bolting.
4. Unscrew diaphragm casing cap screws and nuts (keys 22 and 23), and lift off upper diaphragm casing (key 1).
5. Remove the molded diaphragm (key 2).
6. For actuators without snubber, remove diaphragm plate and stem (keys 4 and 10) as an assembly. This assembly can be broken down further, if necessary, by removing the cap screw (key 3).
7. For actuators with snubber (see figure 7), unscrew cap screw (key 3), and remove diaphragm plate (key 4). Remove stem connector (key 26). Unscrew cap screws (key 85), and remove cylinder assembly (key 74) and attached stem and upper seat (keys 10 and 90) from actuator.
Actuator
This procedure describes how the actuator can be completely disassembled and assembled. When inspection or repairs are required, disassemble only those parts necessary to accomplish the job; then, start the assembly at the appropriate step.
Key numbers refer to figure 4 for size 80 actuators and figure 5 for size 100 actuators.
6
To disassemble snubber:
a. Unscrew stem from piston/piston rod assembly (key 27).
b. Remove retaining rings, cylinder heads, and piston/piston rod assembly (keys 76, 75, and 27). Replace packing and O-rings (keys 103, 104, 77 and 105) as required.
8. Remove actuator spring, upper sleeve, and spring seat (keys 6, 34 and 11).
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