Fisher A31A Manual

D500194X012



Introduction 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Scope of Manual 1. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Description 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Specifications Table 2. . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Valve Orientation 4. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Before Installing the Valve 6. . . . . . . . . . . . . . . . . . . .
Adjusting the Actuator Travel Stops or Travel 7. . . .
Installing the Valve 7. . . . . . . . . . . . . . . . . . . . . . . . . . .
Packing Adjustment and Shaft Bonding 8. . . . . . . . .
Maintenance 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removing and Replacing the Actuator 9. . . . . . . . . .
Packing Maintenance 9. . . . . . . . . . . . . . . . . . . . . . . . .
Removing the Valve 10. . . . . . . . . . . . . . . . . . . . . . . .
Seal Maintenance 11. . . . . . . . . . . . . . . . . . . . . . . . . .
PTFE Seals 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NOVEXR, PhoenixRIII and/or
Phoenix III Fire-Tested Seals
FireTested Seal Installation 12. . . . . . . . . . . . . . .
Anti-Blowout Design, Packing, Valve Shaft,
Disk, and Bearing Maintenance 13. . . . . . . . . . . .
Installing the Two-Piece Shaft 14. . . . . . . . . . . . . . . .
Gasket Retainer 15. . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Ordering 15. . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Reference 16. . . . . . . . . . . . . . . . . . . . . . . . .
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Scope of Manual
This instruction manual includes installation, mainte-
nance, and parts ordering information for Size 14-
through 24-inch, POSI-SEALRModel A31A High-Per-
formance Butterfly Valve (see figure 1). Refer to sep-
Figure 1. Typical Model A31A Valves
W5812-1/IL
W5811-1/IL
arate instruction manuals for information covering the
actuator and accessories.
Only personnel qualified through training or experience
should install, operate, and maintain this control valve.
If you have any questions concerning these instruc-
tions, contact your Fisher Controls sales representa-
tive or sales office before proceeding.
Description
The valve is available in either a flangeless wafer body
or a single-flange (lugged) body design, with a variety
of seals and internal components. The pressure-as-
sisted seal provides tight shutoff against the full ANSI
class pressure range for the specific type. The keyed
shaft combines with a variety of handlevers, hand
wheels, pneumatic piston or spring-and-diaphragm
actuators. Maximum inlet pressure/temperature rat-
ings are consistent with ANSI Class 150 and 300.
Instruction Manual
Form 5291
March 1998 Model A31A

Model A31A
2
Table 1. Specifications
Valve Size and End Connection Styles
J14-, J16-, J18-, J20-, and J24-inch valves,
and in J, wafer-style (flangeless) or Jsingle-
flange (lugged) with raised-face flanges, ANSI
Class 150 or 300
Maximum Pressure Drop(1)
Consistent with ANSI Class 150 and 300 -pressure-
temperature ratings per ASME B16.34-1996 unless
further restricted by values given in figure 2
Shutoff Classification Per ANSI/FCI 70-2-1991
Standard Soft Seal: Bidirectional shutoff Class VI
(bubble-tight)
NOVEX Seal: Unidirectional shutoff Class V (re-
verse flow direction only) Class VI optional
Phoenix III Seal: Bidirectional shutoff Class VI
(bubble-tight)
Phoenix III Seal for Fire-Tested Applications:
Unidirectional shutoff Class VI (reverse flow direc-
tion only)(bubble-tight) For cryogenic seal applica-
tions, consult your Fisher Controls sales office or
sales representative.
Available Seal Configurations
Standard Constructions
See figure 3 and table 2
Standard Construction Materials
See table 2
Flow Characteristic
Modified equal percentage
Flow Coefficients
See Fisher Controls Catalogs 10 and 12
Flow Coefficient Ratio(2)
100 to 1
Noise Levels
See Fisher Controls Catalogs 10 or 12 for sound/
pressure level prediction
Valve In-Line Position
Shaft horizontal. See figure 4
Valve/Actuator Action
With diaphragm or piston rotary actuator, field-re-
versible between:
Jpush-down-to-close (extending actuator rod
closes valve) and
Jpush-down-to-open (extending actuator rod
opens valve)
Valve Body Classification
Face-to-face dimensions are in compliance with
MSS SP68 and API 609 standards; ,Valve bodies
are designed for installation between ANSI B16.5
Class 150 and 300 raised-face flanges
Disk Rotation
Counterclockwise to open(when viewing from the
drive shaft end) through 90 degrees rotation
Shaft Diameter and Approximate Weight
See tables 3 and 4
ENVIRO-SEALRPacking
This optional packing system provides excellent
sealing, guiding, and transmission of loading force
to control liquid and gas emissions. Contact your
Fisher Controls sales office or sales representative
for availability of ENVIRO-SEAL packing (see figure
7)
1. The pressure/temperature limits in this bulletin, and any applicable code or standard limitation should not be exceeded.
2. Ratio of maximum flow coefficient to minimum usable flow coefficient may also be called rangeability.

Model A31A
3
Figure 2. Maximum Pressure-Temperature Ratings
B2335–2/IL

Model A31A
4
Table 2. Material Temperature Ratings
COMPONENT AND MATERIAL OF CONSTRUCTION(1)
TEMPERATURE RANGE
COMPONENT AND MATERIAL OF CONSTRUCTION
(1)
_F_C
Body
WCB carbon steel
CF8M (316 SST) ANSI Class 150
CF8M ANSI Class 300
–20 to 800
–325 to 1000
–325 to 1500
–29 to 427
–198 to 538
–198 to 816
Disk
CF8M (316 SST) w/ or w/o Hard coating
CF8M with CoCr-A edge –325 to 1000 –325 to 1000 –198 to 538 –198 to 538
Shaft
S20910 (Nitronic 50(2))
S17400 (17-4 PH 1025)
S17400 (17-4 PH H1150M)
–325 to 1000
–100 to 850
–320 to 850
–198 to 538
–73 to 454
–196 to 454
Bearings
PEEK(2) (standard)
S31600(3) –100 to 500 –325 to 1500 –73 to 260 –198 to 816
Packing
PTFE Packing and PTFE ENVIRO-SEAL Packing
Graphite packing
Graphite packing with oxidizing media
–65 to 450
–325 to 1500
–325 to 1000
–54 to 232
–198 to 916
–198 to 538
PTFE Seal Ring
Nitrile Backup O-Ring
Neoprene Backup O-Ring
EPR Backup O-Ring
Fluorelastomer Backup O-Ring
PTFE Backup O-Ring
–20 to 200
–45 to 300
–65 to 360
–20 to 400
–100 to 400
–29 to 93
–43 to 149
–54 to 182
–29 to 204
–73 to 204
Seal Ring and
Backup Ring
UHMWPE(4) Seal Ring (Class 150 Only)
Nitrile Backup O-Ring
Neoprene Backup O-Ring
EPR Backup O-Ring
Fluorelastomer Backup O-Ring
PTFE Backup O-Ring
–20 to 200
–45 to 200
–65 to 200
–20 to 200
–100 to 200
–29 to 93
–43 to 93
–54 to 93
–29 to 93
–73 to 93
Phoenix IIIRand/or FireTested Construction
S31600 and PTFE Seal Ring with Nitrile Backup O-Ring
Neoprene Backup O-Ring
EPR Backup O-Ring
Fluorelastomer Backup O-Ring
–40 to 300
–65 to 300
–80 to 400
–40 to 450
–40 to 149
–54 to 149
–62 to 204
–40 to 232
Seal Ring
NOVEX S31600 Seal(3) Ring (Class 150)
NOVEX S31600 Seal(3) Ring (Class 300)
NOVEX S21800 Seal Ring (Class 300)
–20 to 1000
–20 to 1500
–20 to 1500
–29 to 538
–29 to 816
–29 to 816
Seal
Ring
Cryogenic Seal Ring Contact your Fisher Controls sales representative
or sales office
1. NACE trim constructions are available; consult your Fisher Controls sales office or sales representative.
2. PEEK stands for poly-ether-ether-ketone.
3. For a complete material description, contact your Fisher Controls sales office or sales representative.
4. UHMWPE stands for ultra high molecular weight polyethylene.

The valve is normally shipped as part of a control
valve assembly, with the power actuator mounted on
the valve. If the valve or actuator have been pur-
chased separately, or if the actuator has been re-
moved for maintenance, mount the actuator on the
valve, and adjust actuator travel before installing the
valve into the line. This is necessary due to the mea-
surements that must be made during the actuator cal-
ibration adjustment process. Refer to the Actuator
Mounting section of this manual and to the separate
actuator instruction manual for mounting and adjusting
instructions before proceeding.
WARNING
To avoid personal injury or property
damage resulting from the sudden re-
lease of pressure:
DDo not install the valve assembly
where service conditions could exceed
the limits given in this manual or on the
nameplates.
DUse pressure-relieving devices as
required by government or accepted in-
dustry codes and good engineering
practices to protect from over-pressuriz-
ing the system.

Model A31A
5
DThe valve configuration and
construction materials are selected to
meet particular pressure, temperature,
pressure drop, and controlled fluid
conditions. Some body/trim material
combinations are limited in their pres-
sure drop and temperature range capa-
bilities. Do not apply any other condi-
tions to the valve without first
contacting your Fisher Controls sales
office or sales representative.
1. Isolate the control valve from the line pressure, re-
lease pressure from both sides of the valve body, and
drain the process media from both sides of the valve.
If using a power actuator, shut off all pressure lines to
the power actuator, release pressure from the actua-
tor, and disconnect the pressure lines from the actua-
tor. Use lock-out procedures to be sure that the above
measures stay in effect while you are work on the
equipment.
See the WARNING at the beginning of the Mainte-
nance section for more information before removing
the valve from the pipeline.
2. Install a three-valve bypass around the control
valve assembly if continuous operation is necessary
during inspection and maintenance of the valve.
3. Inspect the valve to be certain that it is free of for-
eign material.
4. Be certain that adjacent pipelines are free of any
foreign material, such as pipe scale or welding slag,
that could damage the valve sealing surfaces.
CAUTION
Damage to the disk will occur if any pipe
flanges or piping connected to the valve
interfere with the disk rotation path. If
piping flange has a smaller inner diame-
ter than specified for schedule 80 pip-
ing, measure carefully to be certain the
disk rotates without interference before
placing the valve into operation. Mini-
mum inside diameters for flanges or
pipe mating with valves are shown in
tables 3 and 4.
Valve Orientation
The valve can be installed in any orientation however,
it is recommended that the valve drive shaft be hori-
zontal and the actuator vertical as shown in figure 4.
Install the valve with the high-pressure shutoff side in
the direction noted by the flow arrow for proper instal-
lation, and see figure 4 for more information.
Before Installing the Valve
WARNING
The edges of a rotating valve disk (key
2, figure 9) close with a shearing, cut-
ting motion. To avoid personal injury,
keep hands, tools, and other objects
away from the disk while stroking the
valve.
If the Model A31A valve is equipped with
a fail-open actuator, cycle the valve into
the fully closed position. Ensure the
valve can not open during installation
by using travel stops, a manual actua-
tor, a constant supply pressure to the
pneumatic actuator, or other steps as
necessary.
CAUTION
When using an actuator, the actuator
travel stop (or actuator travel, for actua-
tors without adjustable stops) must be
adjusted so the disk stop in the valve
does not absorb the output of the actua-
tor. Failure to limit the actuator travel as
described in the Adjusting the Actuator
Travel Stops or Travel steps can result
in damage to the valve, shaft(s), or other
valve components.
A Fisher Controls Model A31A valve is normally
shipped as part of an assembly with an actuator and
other accessories such as a valve positioner. If the
valve and actuator have been purchased separately or
if the actuator has been removed for maintenance,
properly mount the actuator and adjust valve/actuator
travel and all travel stops before inserting the valve
into the line.
CAUTION
Damage to the disk will occur if any pipe
flanges or piping connected to the valve
interfere with the disk rotation path. Be
certain to align the valve accurately to
avoid contact between the disk (key 2)
and the flanges.

Model A31A
6
Table 3. Valve Body Data, Class 150
VALVE
SIZE,
INCHES
SHAFT
DIA.
AT YOKE
BEARING
FACE-TO-
FACE
DIMEN-
SION(1)
MINI-
MUM
I.D.(2)
APPROX.
WEIGHT,
POUNDS
INCHES Inches Wafer Single-
Flange
14 1-3/16 3-5/8 13.04 158 209
16 1-1/4 4 14.77 207 304
18 1/2 4-1/2 16.49 307 393
20 1-3/4 5 18.27 368 493
24 2-1/4 6-1/16 22.87 563 773
VALVE
SIZE,
INCHES
SHAFT
DIA.
AT YOKE
BEARING
FACE-TO-
FACE
DIMEN-
SION(1)
MINI-
MUM
I.D.(2)
APPROX.
WEIGHT,
KILOGRAMS
INCHES mm Wafer Single-
Flange
14 30.2 92.1 331.2 71.7 94.8
16 31.75 101.6 375.2 93.9 137.9
18 38.1 114.3 418.8 139.3 178.3
20 44.45 127.0 464.1 166.9 223.6
24 57.15 154.0 580.9 255.4 350.6
1. Face-to-face dimensions are in compliance with MSS SP68 and API 609
specifications.
2. Minimum I.D. is the minimum pipe or flange I.D. required for disk swing clearance.
Table 4. Valve Body Data, Wafer-Style Valves, Class 300
VALVE
SIZE,
INCHES
SHAFT
DIA.
AT YOKE
BEARING
FACE-TO-
FACE
DIMENSI
ON(1)
MINI-
MUM
I.D.(2)
APPROX.
WEIGHT,
POUNDS
INCHES Inches Wafer Single-
Flange
14 1-3/4 4-5/8 11.98 276 510
16 1-3/4 5-1/4 13.63 417 663
18 2-1/4 5-7/8 15.32 524 907
20 2-3/4 6-1/8 17.40 817 1215
24 2-3/4 7-1/8 20.59 1052 1827
VALVE
SIZE,
INCHES
SHAFT
DIA.
AT YOKE
BEARING
FACE-TO-
FACE
DIMEN-
SION(1)
MINI-
MUM
I.D.(2)
APPROX.
WEIGHT,
KILOGRAMS
INCHES mm Wafer Single-
Flange
14 44.45 117.5 304.3 125.2 231.3
16 44.45 133.4 346.2 189.2 300.7
18 57.15 149.2 389.4 237.7 411.4
20 69.9 155.6 442.0 370.6 551.1
24 69.9 181.0 523.2 477.2 828.7
1. Face-to-face dimensions are in compliance with MSS SP68 and API 609
specifications.
2. Minimum I.D. is the minimum pipe or flange I.D. required for disk swing clearance.
Figure 3. Available Seal Configurations
B2334–1/IL

Model A31A
7
Table 5. Hex Head Screw, Stud Bolt and Cap Screw Data
(1)
Valve
Size, No. of Cap Screws No. of Stud Bolts Size-Dia. Inch & Thread Length of Cap
Screws,Inch Length of Stud Bolts,Inch
Size
,
Inches Class 150 Class 300 Class 150 Class 300 Class 150 Class 300 Class 150 Class 300 Class 150 Class 300
Single-Flange Style
(2)
14 24 40 - - - - - - 1-8 1-1/8-8 2-3/4 3-1/2 - - - - - -
16 32 40 - - - - - - 1-8 1-1/4-8 3 3-3/4 - - - - - -
18 32 48 - - - - - - 1-1/8-8 1-1/4-8 3-1/4 4- - - - - -
20 40 48 - - - - - - 1-1/8-8 1-1/4-8 3-1/2 4- - - - - -
24 40 48 - - - - - - 1-1/4-8 1–1/2-8 3-1/2 4-1/2 - - - - - -
Wafer-Style
14 - - - 8 12 16 1-8 1-1/8-8 - - - 3-1/2 9-1/2 12
16 - - - 8 16 16 1-8 1-1/8-8 - - - 3-3/4 10 13-1/2
18 - - - 8 16 16 1-1/8-8 1-1/4-8 - - - 4 11 13-3/4
20 - - - 8 20 20 1-1/8-8 1-1/4-8 - - - 4 12 14-1/2
24 - - - 8 20 20 1-1/4-8 1-1/2-8 - - - 4-1/2 14 16-1/2
1. Thread engagement in accordance with ANSI B31.3-1976 “Chemical Plant and Petroleum Refinery Piping”.
2. Bolting lengths are based on installation of valve between standard raised face flanges and utilizing flange gaskets with a final compression thickness of 1/8 inch. When gaskets
used have a final compression thickness of less than 1/8 inch, reduce bolting lengths shown by 1/4 inch.
Figure 4. Proper Installation Steps
B2263-1/IL
Adjusting the Actuator Travel Stops or
Travel
Key number locations are shown in figure 9, unless
otherwise noted.
1. Refer to the actuator instruction manual to locate
the actuator travel stop that control the closed position
of the valve disk (key 2). When adjusting the travel
stop or travel, make sure that the disk is from 0 to
0.030 inch (0 to 0.76 mm) away from the internal stop
A5557/IL
Figure 5. Properly Installed Wafer-Style Valve
in the valve body. This adjustment is necessary to be
certain that the actuator output torque is fully absorbed
by the actuator travel stop or by the actuator. The in-
ternal travel stop in the valve body should not absorb
any of the actuator torque.
2. Before installing the valve/actuator assembly in the
process line, cycle the valve several times to be sure
the valve disk returns to the proper position.
Installing the Valve
The maximum allowable inlet pressures for Model
A31A valves are consistent with the applicable ANSI
pressure/temperature ratings except where limited by
the material capabilities as shown in table 2 or figure
3.
Refer to table 5 for the quantity and size of line bolting
required to install the valve in the pipeline.

Model A31A
8
CAUTION
To avoid damage to the valve disk dur-
ing installation, the valve must be in the
fully closed position. If the Model A31A
valve is equipped with a fail-open actua-
tor, remove the actuator before instal-
ling the valve/actuator assembly or
cycle the valve into the fully closed
position. Then, take appropriate steps to
be sure that the actuator does not cause
the valve to open during installation.
1. See figure 4 for recommended valve orientation.
DFor Wafer-Style Valves: Install the lower flange
bolts first to form a cradle for the valve (see figure 4).
See table 5 for flange bolt specifications.
DFor Single-Flange Valves: Position the valve
between the flanges. Be sure to leave enough room
for the flange gaskets. Install the lower flange bolts.
2. For all Valves: Select the appropriate gaskets for
the application. Flat sheet, spiral wound, or other gas-
ket types, made to the ANSI B16.5 standard or user’s
standard, can be used on Model A31A valves depend-
ing on the service conditions of the application.
3. For Wafer-Style Valves: Properly orient the valve
according to the specific application. Place the valve in
the line so the flow properly enters the valve as indi-
cated by the flow tag. Then, install the valve and the
gaskets between the flanges into the cradle formed by
the flange bolts.
4. Install the remaining flange bolts.
DFor Wafer-Style Valves: Make sure the gaskets
are centered on the gasket sealing surfaces of the
flange and body.
5. For all Valves:Tighten the flange bolts in an alter-
nating criss-cross fashion to a torque value of one-
fourth of the final bolting torque. Repeat this procedure
several times, increasing the torque value each time
by a fourth of the final desired torque. After applying
the final torque value, tighten each flange bolt again to
allow for gasket compression.
Packing Adjustment and Shaft Bonding
WARNING
Personal injury could result from pack-
ing leakage. Valve packing was tight-
ened before shipment; however, the
packing might require some readjust-
ment to meet specific service condi-
tions.
1. For PTFE or graphite packing: Tighten standard
packing follower nuts only enough to prevent shaft
leakage. Excessive tightening of packing will acceler-
ate wear and could produce higher rotating friction
loads on the valve stem. If necessary, refer to the
Packing Maintenance section.
2. For ENVIRO-SEAL Packing Systems: will not
require this initial re-adjustment. Refer to the separate
ENVIRO-SEAL Packing System–Rotary Valves In-
struction Manual, Form 5305 for repair and adjustment
procedures.
3. For hazardous atmosphere or oxygen service
valves, read the following Warning, and provide the
bonding strap assembly mentioned below if the valve
is used in an explosive atmosphere.
WARNING
The valve drive shaft is not necessarily
grounded to the pipeline when installed.
Personal injury or property damage
could result, if the process fluid or the
atmosphere around the valve is flam-
mable, from an explosion caused by a
discharge of static electricity from the
valve components. If the valve is
installed in a hazardous area, electrical-
ly bond the drive shaft to the valve.
Note
The packing is composed of all conduc-
tive packing rings (graphite ribbon
packing) to electrically bond the shaft to
the valve for hazardous area service or
non-conductive PTFE packing rings. For
oxygen service applications, provide al-
ternate shaft-to-valve body bonding ac-
cording to the following step.
4. Attach the bonding strap assembly (key 131, figure
6) to the shaft with the clamp (key 130, figure 6).
5. Connect the other end of the bonding strap assem-
bly to the valve flange cap screws.
6. For more information, refer to the Packing Mainte-
nance section below.

Model A31A
9
Figure6.OptionalShaft-to-ValveBodyBondingStrapAssembly
VALVE BODY ACTUATOR
A
AVIEW A-A
37A6528-A
A3143-2/IL

Valve parts are subject to normal wear and must be
inspected and replaced as necessary. The frequency
of inspection and replacement depends upon the se-
verity of service conditions. Because of the care Fish-
er Controls takes in meeting all manufacturing require-
ments (heat treating, dimensional tolerances, etc.),
use only replacement parts manufactured or furnished
by Fisher Controls.
Key numbers in this procedure are shown in figure 9
unless otherwise indicated.
WARNING
Avoid personal injury from sudden re-
lease of process pressure. Before per-
forming any maintenance operations:
DDisconnect any operating lines pro-
viding air pressure, electric power, or a
control signal to the actuator. Be sure
the actuator cannot suddenly open or
close the valve.
DUse bypass valves or completely
shut off the process to isolate the valve
from process pressure. Relieve process
pressure on both sides of the valve.
Drain the process media from both
sides of the valve.
DVent the power actuator loading
pressure.
Removing and Replacing the Actuator
Refer to the appropriate actuator instruction manual
for actuator removal and replacement procedures. The
actuator stops or travel stops must limit the rotation of
the valve shaft. See the CAUTION below.
CAUTION
When using an actuator, the actuator
travel stop (or actuator travel stop, for
actuators without adjustable stops)
must be adjusted so the disk stop in the
valve does not absorb the output of the
actuator. Failure to limit the actuator
travel can result in damage to the valve,
shaft(s), or other valve components.
Packing Maintenance
The Fisher Controls Model A31A control valve is de-
signed so the packing can be replaced without remov-
ing the valve from the process pipeline.
CAUTION
For non-ENVIRO-SEAL packing: Tighten
the packing follower nuts only enough
to prevent shaft leakage. Excessive
tightening will accelerate wear of the
packing and could produce higher fric-
tion loads on the valve stem.
Usually, packing leakage can be eliminated by merely
tightening the hex nuts (key 15) located above the
packing follower (key 11) while the valve is in the pipe-
line. However, if leakage continues, the packing must
be replaced.
For PTFE ENVIRO-SEAL packing system, refer to the
instruction manual ENVIRO-SEAL Packing Systems
for Types 8522,8532: Models A11, A31, A31A,A41
and B21A Form 5320.
CAUTION
Never use a wrench or pliers on the
splined (upper) shaft (key 3). A damaged
shaft could cut the packing and allow
leakage.

Model A31A
10
Figure 7. Anti-Blowout Design Details
C0758-1/IL 
1. Before loosening any parts on the valve, release
the pressure from the pipeline. Then, remove the hex
nuts (key 15) and lift off the packing follower (key 11).
2. Remove the hex jam nuts (key 16, figure 9) and the
anti-blowout gland (key 10). Remove the packing fol-
lower (key 12). Refer to figure 7 for details of the anti-
blowout protection parts.
The packing is now accessible.
3. Use a packing extractor to remove packing. Insert
the corkscrew-like end of the tool into the first piece of
packing and pull firmly to remove the packing. Repeat
this process until all packing parts have been re-
moved.
CAUTION
Be careful when cleaning the packing
box. Scratches to the upper shaft (key 3)
or inside diameter of packing bore
might cause leakage.
4. Before installing new packing, clean the packing
box.
5. Install new packing one ring at a time, using the
packing follower as a driver. If using split-ring packing,
stagger the splits in the rings to avoid creating a leak
path.
6. Reinstall packing parts. Refer to figure 9 for se-
quence of packing parts.

Model A31A
11
Table 6. Torque Values for Fasteners
FASTENER NOMINAL SIZE
#10 1/4 5/16 3/8 7/16 1/2 9/16 5/8 3/4 7/8 1 1-1/8
Retainin
g
Pounds-inch Pounds-Foot
Retaining
Ring 41 100 220 400 53 83 119 166 296 480 720 1000
Ring
Screws NewtonSmeters
4.6 11 25 45 72 112 161 225 401 651 976 1356
G
Pounds-inch Pounds-Foot
Gasket
Retaining
35 81 167 295 39 59 86 119 210 330 480 617
Retaining
Bolts
NewtonSmeters
Bolts
4.0 9.2 19 33 53 80 117 161 286 447 651 837
Nore: These values are based upon standard materials, S66286/Inconel screws and ASTM A193GRB6 bolts. For other special fasterer materials, please contact your Fisher Controls
sales office or sales representative.
Figure 8. Typical Seal Installation
A5251-1*/IL
Removing the Valve
1. Disconnect any operating lines providing air pres-
sure, electric power, or a control signal to the actuator.
Be sure the actuator cannot suddenly open the valve.
Vent the power actuator loading pressure.
2. Use bypass valves or completely shut off the pro-
cess to isolate the valve from process pressure. Re-
lieve process pressure on both sides of the valve.
Drain the process media from either side of the valve.
CAUTION
Damage to the valve disk can occur if
the disk is not closed when the valve is
being removed from the pipeline. If nec-
essary, stroke the actuator to place the
disk in the closed position while remov-
ing the valve from the pipeline.
3. Loosen the flange bolting that holds the valve.
Make sure the valve cannot slip or twist while loosen-
ing and removing the bolting.
4. Before removing the valve from the pipeline, make
sure the valve disk is closed. Removing the valve with
the disk open could cause damage to the disk, piping,
or pipe flanges.
5. After removing the valve from the pipeline, move
the valve to an appropriate work area. Always support
the valve properly.
6. When valve maintenance is complete, refer to the
Installation procedures in this manual.
Seal Maintenance
Note
For larger valves, it is possible to re-
place the seal (key 5) while the actuator
is mounted to the valve and can be ac-
complished by cycling the valve to 90
degrees open.
Key numbers in this procedure are shown in figure 9
unless otherwise indicated.
1. After removing the valve from the pipeline, remove
the manual or power actuator. Manually rotate the up-
per shaft (key 3) counterclockwise until the disk has
moved a full 180 degrees away from the closed posi-
tion.
WARNING
Avoid personal injury or property dam-
age caused by the impact of a falling or
tipping of a large valve. Support large
valves during maintenance.

Model A31A
12
2. Lay the valve flat on a work bench in a secure posi-
tion with the retaining ring (key 18) and retaining ring
screws (key 19) facing up. Properly secure the valve
on a suitable worktable so it can not slip, twist, or fall
during maintenance. Remove all retaining ring screws.
3. Remove the retaining ring by placing a socket head
cap screw from the retaining ring in each of the two
retaining ring jacking screw holes. Slowly turn the
screws until the retaining ring has been lifted from the
valve body. Remove the retaining ring to expose the
seal in the T-slot area of the valve body.
Note
The Fisher Controls Model A31A is
available with different seal designs and
components. See figure 2 to identify the
specific seal design.
4. Insert a regular screw driver or other similar tool
under the top edge of seal and gently pry the seal out
of the T-slot area in the valve body. Take care not to
damage the seal or T-slot area of the valve body. After
the seal has been removed, clean the T-slot area, re-
taining ring and, if required, polish the disk (key 2)
thoroughly with fine steel wool or other appropriate
material.
To install a new seal, O-ring (key 6), and retaining ring
gasket, follow the appropriate instructions given below.
PTFE Seals
A maintenance kit with installation tools is available
through your Fisher Controls sales office or sales rep-
resentative.
1. Locate the replacement seal ring (key 5) and note
the shape of the ring. The ring is wider across one
edge diameter and narrower across the other edge
diameter as shown in figure 8. Around the outside cir-
cumference is one wide groove.
Before installing the seal ring into the valve body,
place the O-ring (key 6) into the wide, outer groove of
the seal ring. Refer to figure 7.
2. Install the seal ring and O-ring assembly in the
valve body. The wider outside diameter of the seal
ring, as marked in figure 8, goes into the T-slot area of
the body (see figure 5). Start the edge with the wider
diameter into the T-slot of the valve body using a
blunt-end screwdriver. If you have a maintenance kit,
use the seal installation tools.
3. Carefully tuck the O-ring downward into the body
T-slot until the seal ring is completely entrapped in the
body T-slot, and it completely covers the backup O-
ring.
4. Re-install the retaining ring and the socket head
cap screws. Tighten the cap screws just enough to
eliminate any movement of the retaining ring. Do not
over-tighten the retaining ring screws. Using a blunt-
end tool, carefully tuck the lip of the seal ring under
the retaining ring.
5. When the seal is under the lip of the retaining ring,
continue to tighten the cap screws according to stan-
dard procedures. Do not fully torque screws at this
time. Final tightening of screws is accomplished in
step 7 of this procedure.
6. Manually rotate the upper shaft clockwise 180 de-
grees to return the disk (key 2) to its closed position.
7. The final seating of the retaining ring cap screws
can now be done. For the screw torque values, refer
to table 6. The seal is now fully installed. Refer to the
Installation procedures in this manual.
NOVEX, Phoenix III and/or Phoenix III
Fire-Tested Seals
A maintenance kit with installation tools is available
through your Fisher Controls sales office or sales rep-
resentative.
1. Locate the replacement seal ring (key 5) and note
the shape of the ring. The ring is wider across one
edge diameter and narrower across the other edge
diameter as shown in figure 8. Around the outside cir-
cumference is one wide groove.
Install the seal ring (key 5) in the valve body by first
placing the wider outside diameter of the seal ring into
the T-slot area of the valvebody which is shown in fig-
ure 3.
The backup O-ring (key 6) for the Phoenix III seal will
have to be installed after placement of the seal ring in
the valve body using a blunt-end screwdriver or the
seal installation tool in the maintenance kit. Do not use
the screwdriver or seal tool directly on the metal seat.
Use tools on the O-ring only.
2. With the seal ring inserted all the way around the
body T-slot now lay the O-ring into the opening be-
tween the valve body and the seal ring. Use the seal
tool to apply pressure to the O-ring and carefully tuck
the O-ring down into the T-slot between the valve
body and the seal ring.

Model A31A
13
Note
On larger valves, it may be more effi-
cient to have someone hold down the
seal ring while you push the O-ring into
the T-slot.
3. Once the seal ring and backup O-ring has been
fully installed into the body T-slot, the retaining ring
gasket can be installed. This gasket is a thin graphite
material. Be careful. Do not damage the gasket. How-
ever, punch one initial screw hole through the gasket
for alignment.
4. Install the retaining ring and align the screw holes
in the retaining ring with the holes in the valve body.
Install the first retaining ring screw through the
punched hole in the ring gasket. Install the other ring
screws by pushing the screws through the graphite
gasket and threading them into the valve body.
5. Tighten the retaining ring socket head cap screws
just enough to eliminate any movement of the retain-
ing ring. Do not over-tighten the retaining ring screws.
WARNING
Avoid personal injury or property dam-
age caused by the impact of a falling or
tipping of a large valve. Support large
valves during maintenance.
6. To complete this step, stand the valve up. Support
the valve securely using methods appropriate for the
valve size. If a vise or other clamps are being used, be
sure to not damage the flange gasket sealing area of
the valve body.
7. Manually rotate the upper shaft (key 3) to turn the
disk clockwise to meet the seal.
8. Tap the disk with a rubber mallet to drive it against
the internal travel stop. When the disk makes contact
with the stop, manually rotate the disk counterclock-
wise back out of the seal to a 90-degree open position.
Repeat steps 7 and 8 three times.
Note
When attaching the actuator to the
valve, make sure the valve disk is not in
contact with the valve internal travel
stop (see figure 5). The valve disk
should be positioned from 0 to 0.030
inch (0 to 0.76 mm) away from the inter-
nal stop in the valve body (see figure 5).
9. Use an appropriate tool (such as a feeler gauge) to
position the disk (key 2) from 0 to 0.030 inch (0 to 0.76
mm) away from the internal stop in the valve body.
This adjustment is necessary to be certain that the
actuator output torque is fully absorbed by the actua-
tor travel stop or by the actuator. The internal travel
stop in the valve body should not absorb any of the
actuator torque.
10. The final seating of the retaining ring screws can
now be done. For the screw torque values, refer to
table 6.
Anti-Blowout Design, Packing, Valve
Shaft(s), Disk, and Bearing Maintenance
Note
The A31A valve has a two-piece shaft. In
these procedures, the shaft (with the
splined end) is called the upper shaft
(key 3). The shaft opposite the upper
shaft is called the lower (follower) shaft
(key 4).
CAUTION
When using an actuator, the actuator
travel stop (or actuator travel adjust-
ment, for actuators without adjustable
stops) must be adjusted so the disk
stop in the valve does not absorb the
output of the actuator. Failure to limit
the actuator travel as described in the
next step can result in damage to the
valve, shaft(s), or other valve compo-
nents.
CAUTION
When removing the actuator from the
valve, do not use a hammer or similar
tool to drive the lever off the valve shaft.
Driving the lever or actuator off the
valve shaft could damage the valve in-
ternal parts.
If necessary, use a wheel puller to re-
move the lever or actuator from the
valve shaft. It is okay to tap the wheel
puller screw lightly to loosen the lever
or actuator, but hitting the screw with
excessive force could also damage in-
ternal valve parts.
Key numbers in this procedure are shown in figure 9
unless otherwise indicated.

Model A31A
14
1. Remove the valve from the pipeline. Remove the
actuator from the valve.
CAUTION
Never use a wrench, pliers, or similar
tool to turn the upper shaft. A damaged
shaft can cut the packing and allow
leakage.
Note
It is not necessary to remove the retain-
ing ring and valve seal when removing
the shaft(s) and disk.
2. Properly secure the valve on a suitable worktable
so it can not slip, twist, or fall during maintenance.
3. Removing the Anti-Blowout Design:
a. For PTFE or Graphite Packing: Remove the
hex nuts (key 15) and pull off the packing follower
(key 11). Remove the hex jam nuts (key 17, figure
9 or key 16, figure 9) and the anti-blowout follower
(key 10). Remove the anti-blowout gland (key 12).
Also, see figure 7.
b. For ENVIRO-SEAL Packing System: Remove
the hex nuts (key 101), the packing follower (key
102), jam nuts (key 17), anti-blowout follower (key
10), and the spring pack assembly (key 103).
4. Remove the packing from around the upper shaft.
5. Remove the tangential pins or disk pins. Locate the
pins (key 9) in the upper shaft (key 3) and the pin in
the lower shaft (key 4), if the valve has a two-piece
shaft.
a. If a maintenance kit is available, use the pin ex-
tractor to remove the disk pins. Select the correct
size pin extractor tip with screws of proper thread
size to match the thread size in the disk pins. If you
do not have a kit, see steps c and d below.
b. Screw the pin extractor tip into the pin as far as
possible. With an upward, straight sliding motion,
pull out the pin. Repeat the same procedure for the
other pins.
c. You can use a threaded rod with an appropriate
spacer (tube) and nut as an extractor tool. If you
use a threaded rod, choose a rod with threads that
fit the inside thread of the pins. The rod should ex-
tend several inches above the disk when it is
screwed into a pin.
d. After screwing the rod into the pin, slide the
spacer over the rod and pin. Thread a nut onto the
rod and tighten it. As you tighten the nut, the nut
will drive the spacer against the disk. The increas-
ing force will draw the pin from the disk.
6. The gasket retainer (keys 19 and 20, figure 9) on
the side of the valve opposite the upper shaft must be
removed before removing the lower shaft.
Remove the hex head bolts (key 22) and lockwashers
(key 21) from the gasket retainer and remove the gas-
ket retainer and gasket (key 20) to expose the end of
the lower shaft.
7. Before removing the lower shaft (key 4), be sure
the valve disk is properly supported. Pull the lower
shaft from the valve body. Use a shaft extractor
screwed into the puller hole in the end of the lower
shaft.
8. Before removing the upper shaft (key 3), be sure
the valve disk is properly supported. Pull out the upper
shaft (key 3) by hand-pulling or by using a shaft ex-
tractor screwed into the end of the shaft.
CAUTION
To avoid damage to the disk, seal, and
T-slot area, do not force the disk past
the seal or T-slot area. Remove the disk
from the opposite side of the valve
body.
Note
Both the upper shaft and the lower shaft
have a thrust bearing (key 24, figure 9)
between the disk and the bearings (key
7, figure 9). The thrust bearing is located
outside of the bearing bore which holds
the bearings. Use care when removing
the valve disk to avoid loss of or dam-
age to the thrust bearings.
9. After removing the shaft(s), remove the disk. Do
not force the disk past the seal or T-slot area. Collect
the thrust bearings.
10. Remove the bearings (key 7). Using a suitable
punch or puller, drive or pull the bearings into the
valve body bore from the upper shaft bearing bore.
Remove the bearing from the lower shaft bearing bore.

Model A31A
15
11. Inspect the valve body bore, bearings, bearing
bores, and packing box for damage.
Note
In these instructions, the drive shaft
(with splined end) is called the upper
shaft (key 3). The shaft opposite the up-
per shaft is called the lower (follower)
shaft (key 4).
Installing the Two-Piece Shaft
Key numbers in this procedure are shown in figure 9
unless otherwise indicated.
1. Properly secure the valve on a suitable worktable
so it can not slip, twist, or fall during maintenance. Be
prepared to support the valve disk. Allow for easy ac-
cess to the valve body bore, drive shaft bearing bore
and follower shaft bearing bore.
Note
Replacement disk and shafts are pro-
vided as a matched set and both should
be replaced at the same time.
2. Inspect all parts removed from the valve for wear
or damage. Replace any worn or damaged parts.
Clean the valve body and all parts to be installed with
an appropriate solvent or degreaser. Note: When
installing the bearings, apply lubricant to the outside
diameter of the bearing for ease of installation.
CAUTION
Premature valve failure and loss of pro-
cess control may result if bearings are
improperly installed or are damaged
during installation.
3. When installing the lower bearings (key 4), insert
bearings into the drive shaft bearing bore so one end
is flush with the body bore and the other end is flush
with the interior end of the packing box.
Two bearings are required in the upper shaft and two
bearings in the lower shaft. If using a 14-inch Class
150 valve with metal bearings, four bearings in the
upper and four in the lower shaft will be required.
4. Insert one bearing from the valve body bore into
the follower shaft bearing bore so it is flush with the
valve body bore.
5. Insert the drive shaft into the valve body through
the packing box. Push the drive shaft throught the
bearing. Hold the drive shaft drive bearing (key 24) in
the valve body bore against the opening of the drive
shaft bearing bore. Push the drive shaft through the
bearing bore just enough to hold the thrust bearing.
6. Insert the follower shaft through the bore in the
valve body uncovered by removal of the gasket retain-
er. Hold the follower shaft thrust bearing (key 24) in
the valve body bore against the opening of the follower
shaft bearing bore. Push the follower shaft through the
bearing bore just enough to hold the thrust bearing.
7. Install the valve disk. Place the flat side of the disk
on a flat surface, then move the valve body from its
upright position and suspend the valve body over the
disk so the seal ring/T slot area is facing up. Align the
shaft bores through the disk with the drive shaft and
follower shaft bores. Lower the valve body over the
disk using caution not to dislodge or damage the thrust
bearing s placed on the ends of the shafts.
8. With the valve disk properly positioned in the valve,
push the drive shaft and follower shaft the rest of the
way through the thrust bearings and into the shaft
bores in the valve disk.
CAUTION
To avoid damage to the disk, seal, and
T-slot area, do not force the disk past
the seal or T-slot area. Install the disk
from the opposite side of the valve
body.
9. Align the holes in the shafts with the holes in the
disk.
CAUTION
To avoid damage to the tangential pins,
disk pins, valve disk, or shaft(s) result-
ing from the application of excessive
force, use appropriate care when driving
the pins into the disk hub and shaft(s).
Use the right tool. Do not use excessive
force.
10. Install the appropriate tangential pins, and disk
pins. Use 3 tangential pins that will go through the up-
per shaft and 1 disk pin that will go through the lower
shaft.
11. Refer to Packing Maintenance and the Anti-Blow-
out Design procedures in this manual to re-install the
packing and anti-blowout design.

Model A31A
16
Gasket Retainer
Valves with a two-piece shaft (see table 10) use a
gasket retainer and gasket (keys 20 and 21) to cover
the lower shaft opening in the valve body. The gasket
is held in place by the gasket retainer and four hex
head bolts and lockwashers (keys 23 and 22). When
re-assembling the valve, use a new gasket.
Be sure to center the gasket over the lower shaft bore
before retightening bolts. Tighten down bolts evenly in
a crossover or star pattern.
Refer to table 6 for proper torque values.

When replacement parts are required, always use
genuine Fisher Controls parts.
Typical parts are shown in figures 10 and 11. Recom-
mended spare parts include only the following: seal
ring (key 5), backup O-ring (key 6), bearings (key 7),
taper key/tangential pin/disk pin (key 9), packing (key
13), and gasket (key 20) for the lower shaft opening.
When corresponding with your Fisher Controls sales
representative or sales office about a Model A31A
valve, please identify the valve as a Model A31A and
provide the valve serial number. For valve/actuator
combinations assembled at the factory, the valve seri-
al number is stamped on the nameplate attached to
the actuator.

Key Description
1 VALVE BODY
2 DISK
3 DRIVE SHAFT
4 FOLLOWER SHAFT
5 SEAL RING
6 BACKUP RING
7 JOURNAL BEARING
8 BEARING STOP
10 ANTI-BLOWOUT FLANGE
11 PACKING FLANGE
12 PACKING FOLLOWER
13 PACKING
14 STUD
15 HEX NUT
16 ANTI-BLOWOUT RING
17 HEX JAM NUT
18 RETAINING RING
19 RETAINING RING SCREW
20 GASKET RETAINER
21 GASKET
22 LOCKWASHER
23 HEX HEAD BOLT
24 THRUST BEARING
25 KEY (FOR DRIVE SHAFT)
26 TANGENTIAL PIN OR DISK PIN
27 RETAINING RING GASKET, GRAPHITE
29 NAMEPLATE (NOT SHOWN)
30 DRIVE SCREW (NOT SHOWN)
33 FLOW DIRECTION ARROW (NOT SHOWN)

Model A31A
17
Figure 9. Model A31A Wafer Style Valve Assembly
B2388/IL

Model A31A
18
For information, contact Fisher Controls:
Marshalltown, Iowa 50158 USA
Cernay 68700 France
Sao Paulo 05424 Brazil
Singapore 128461


Printed in U.S.A.
EFisher Controls International, Inc. 1991, 1998; All Rights Reserved
ENVIRO-SEAL, POSI-SEAL, NOVEX, Phoenix III, Fisher, Fisher-Rosemount, and Managing The Process Better are marks owned by Fisher Controls International, Inc. or Fisher-Rose-
mount Systems, Inc.All other marks are the property of their respective owners.