Emerson FL User manual

FL Series
D103068X012
InstructionManual
Form5733
July 2004
www.FISHERregulators.com
FL Series Pressure Reducing Regulators
Introduction
Scope of Manual
Thismanual provides instructions for installation,
adjustment,maintenance, and parts ordering forthe FL
Seriesregulators.
Description
TheFLSeriesregulatorsareaccuratepilot-operated,
pressurebalanced, soft seatedregulatorsdesignedfor
high pressure transmission/city gate, large capacity
distribution systems and power plant feeds. The FL
Seriesprovides smooth, quiet operation,tightshutoffand
longlife. Theregulator utilizes a main valve actuator,a
TypePRXpressurereducingpilot, and aTypeSA/2pilot
supplypressureregulator. TheTypePRX pilotusesinlet
pressurereducedbyaType SA/2supplypressure
regulator,asloadingpressureto operatethemainvalve
actuator. The outlet pressure is sensed through a
controllineonthe main valve actuator and also on the
TypePRXpilotdiaphragm.
Specifications
TheSpecificationssection gives some general specifi-
cationsfor the FL Seriesregulators. The nameplates
givedetailed information for a particularregulatoras it
comes from the factory.
Type FL
E0820
Type MFL with Type SRS Silencer
E0821
Figure 1. Type FL and Type MFLwith Type SRS Silencer

FL Series
2
1. The pressure/temperature limits in this instruction manual or any applicable standard limitation should not be exceeded.
Specifications
Available Configurations
FL: Pilot-operatedpressurereducingregulator
formedium to high outlet pressures
MFL: Monitor and regulator combined into a single
unitforoverpressure protection
Body Sizes
FL and MFL:
1, 1-1/2, 2, 2-1/2, 3, 4, and 6-inch (DN 25, 40, 50, 65,
80,100,and150) (6-inchforFLonly)
FL and MFL with SRS Silencer (inlet x outlet):
1 x 4, 1-1/2 x 6, 2 x 6, 2-1/2 x 8, 3 x 10, 4 x 10, and
6 x 12-inch (DN 25 x 100, 40 x 150, 50 x 150,
65 x 200, 80 x 250, 100 x 250, and 150 x 300)
(6x12-inchforFLonly)
Main Valve End Connection Style and Pressure
Ratings(1)
ANSI Class 300 RF: 740psig(51,0) bar
ANSI Class 600 RF: 1450psig(100) bar
Maximum Inlet and Outlet (Casing) Pressure(1)
1450psig(100bar)
Maximum Emergency (Design Pressure)
1450psig(100bar)
Miminum Operating Differential Pressure
7.3 psid (0,5 bar d)
Outlet Pressure Ranges
EPYT ERUSSERPTELTUO (GISP,EGNARrab) GNIRPS ROLOC
021/XRP 521/XRP
61ot3.7 62ot5.41 44ot32 08ot14 321ot37 )1,1ot5,0( )
8,1ot1( )3ot6,1( )5,5ot8,2( )5,8ot5(
etihW wolleY neerG eulB kcalB
012ot611 433ot302 534ot913 906ot124 )5,41ot8( )3
2ot41( )03ot22( )24ot92(
revliS dloG munimulA deR
PA-021/XRP PA-521/XRP 0611ot534)08ot03(raelC
Pressure Registration
External
Maximum Temperature Capabilities(1)
–20°to 150°F (–29° to 66°C)
Principle of Operation
Thepilot-operatedType FL(figure 2)usesinlet pres-
sure as the operating medium, which is reduced
throughpilot operation to loadthe actuator diaphragm.
Outletordownstream pressure opposes loading
pressure in the actuator and also opposes the pilot
controlspring.
When outlet pressure drops below the setting of the
pilot control spring, pilot control spring force on the pilot
diaphragmthusopensthepilotvalveplug,providing
additionalloadingpressure to the actuator diaphragm.
Thisdiaphragmloadingpressureopensthemain valve
plug,supplying the required flow tothe downstream
system. Any excess loading pressure on the actuator
diaphragmescapesdownstreamthroughthe bleed
restriction in the pilot.
When the gas demand in the downstream system has
been satisfied, the outlet pressure increases. The
increasedpressure is transmitted through thedown-
stream control line and acts on the pilot diaphragm. This
pressureexceedsthepilot spring setting and moves the
diaphragm,closingthe orifice. The loading pressure
actingonthemaindiaphragm bleeds to the downstream
system through a bleed restriction in the pilot.
Adjustment
Theadjustmentof the regulator is performedbymeans
ofthepilotadjusting screw,whichvariesthe compres-
sionof the control spring. Adjustmentis performed while
the regulator is in operation with the aid of a test pres-
suregaugeofsuitable range or of a water column. The
shutoffvalve downstream oftheregulator must notbe
completely closed; it is necessary that a small quantity
ofgas flows downstream to allowthe outlet side to vent
down, when it is necessary to lower the pressure.
Loosen the locknut and turn the adjusting screw slowly to
adjust outlet pressure. Use a pressure gauge to check
theoutletpressureuntilthedesired pressure is reached.
Monitoring Systems
Monitoringregulationisoverpressureprotection by
containment,therefore, there is no relief valvetovent to
theatmosphere. When the working regulator fails to
controlthe pressure, a monitor regulator installed in
series, which has been sensing the downstream and
control pressure, goes into operation to maintain the
downstreampressure at a slightlyhigher than normal
pressure. Duringanoverpressure situation, monitoring

FL Series
3
keeps the customer on line.Also, testing is relatively
easy and safe. To perform a periodic test on a monitor-
ing regulator, increase the outlet set pressure of the
workingregulator and watch theoutlet pressure to
determineif the monitoring regulatortakes over at the
appropriateoutletpressure.
Wide-Open Monitoring Systems (figure 3)
Thereare two types of wide-openmonitoring systems:
upstreamanddownstream. The difference between
upstreamand downstream monitoring is that the
functionsof the regulators arereversed. Systems can
bechangedfrom upstream to downstream monitoring,
andvice-versa, by simply reversingthe setpoints of the
two regulators. The decision to use either an upstream
or downstream monitoring system is largely a matter of
personalpreferenceor companypolicy.
Innormaloperationofawide-openconfiguration,the
working regulator controls the system’s outlet pres-
sure. With a higher outlet pressure setting, the monitor
regulator senses a pressure lower than its setpoint and
tries to increase outlet pressure by going wide-open. If
theworkingregulator fails, the monitoring regulator
assumes control and holds the outlet pressure at its
outletpressure setting.
Figure 2. Type FL Operational Schematic
E0827
INLET PRESSURE
OUTLET PRESSURE
LOADING PRESSURE
PILOT SUPPLY PRESSURE
ATMOSPHERIC PRESSURE
Working Monitoring Regulators (figure 3)
Ina working monitoring system,the upstream regulator
requires two pilots and it is always the monitoring
regulator.The additional pilot permitsthemonitoring
regulator to act as a series regulator to control an
intermediatepressureduring normal operation. In this
way, both units are always operating and can be easily
checkedforproperoperation.
Innormal operation, the working regulatorcontrols the
outlet pressure of the system. The monitoring
regulator’sworking pilot controls the intermediate
pressure and the monitoring pilot senses the system’s
outletpressure. If the workingregulator fails, the
monitoring pilot will sense the increase in outlet
pressure and take control.
Note
The working regulator must be rated for
the maximum allowable operating
pressure of the system because this will
be its inlet pressure if the monitoring
regulator fails. Also, the outlet pressure
rating of the monitoring pilot, and any
other components that are exposed to

FL Series
4
the intermediate pressure must be rated
for full inlet pressure.
Working monitor installations require aType FL main
valvewithaType PRX/120 or PRX/120-APworkingpilot
andaTypePRX/125orPRX/125-APmonitoring pilot for
theupstream regulator and aTypeFLwiththe appropri-
ateTypePRX/120orPRX/120-APpilot for the down-
streamregulator. The Type MFLincorporates the
monitor and regulator into one compact unit.
Installation and Startup
Personal injury or equipment damage,
dueto burstingof pressure-containing
parts may result if this regulator is over-
pressured or is installed where service
conditions could exceed the limits given
in the Specification section and on the
appropriate nameplate, or where condi-
tions exceed any rating of the adjacent
piping or piping connections.
To avoid such injury or damage, provide
pressure-relievingor pressure-limiting
devices to prevent service conditions from
exceeding those limits. Also, check that
the installation is in compliance with all
applicable codes and regulations.
Additionally, physical damage to the
regulator could break the pilot off the
main valve, causing personal injury and
property damage due to bursting of
pressure-containing parts. To avoid such
injury and damage, install the regulator in
a safe location.
Single Pilot Regulator
Installation
AType FL regulator bleeds no gas to atmosphere
duringnormal operation, thus making the regulator
suitable for installation in pits and other enclosed
locations without elaborate venting systems. This
regulator also can be installed in pits subject to
floodingby venting the pilot springcaseabove the
expected flood level so that the pilot setting can be
referencedtoatmosphericpressure.
1. Usequalifiedpersonnelwhen installing, maintain-
ing, or operating this regulator. Inspect the regulator
andthe pipeline to be certain both are free of foreign
materials.
2. Install the regulator so that the flow arrow cast on
themain valve matches the flow direction of process
fluidthroughtheregulator.
3. Apply pipe compound to the male pipeline threads
beforeinstallinga regulator with screwed end connec-
tions. Use gaskets between pipeline and regulator
flangeswheninstalling a regulator with flanged end
connections.
A regulator may vent some gas to the
atmosphere. In hazardous or flammable
gas service, vented gas may accumu-
late, causing personal injury, death, or
property damage due to bursting of
pressure-retaining parts. Vent a regula-
tor in hazardous gas service to a re-
mote, safe location away from air
intakes or any hazardous location. The
vent line or stack opening must be
protected against condensation or
clogging.
4. AType PRX pilot has a 1/4-inch NPT vent connec-
tion in the spring case. To remotely vent gas from the
springcase, remove the screened vent,and connect
1/4-inch piping or tubing to the spring case connection.
Thepiping or tubing shouldvent to a safe location,have
asfew elbows as possible, and have a screened vent
on its exhaust. Install the regulator and any remote
vent piping or tubing so that the vent is protected from
condensation, freezing, or any substance that could
clog it.
5. Connect a pilot supply line from the upstream
piping to the 1/4-inch NPT pilot inlet.
6. Connect a downstream control line to a straight
run of pipe 6 to 10 pipe diameters from the regulator
outlet as shown in figure 3. If such a distance is not
practical, connect the control line away from elbows,
swages,nipples, or any area where abnormalflow
velocitiesoccur.
7. Install a hand valve in the control line.
8. Install the other end of the downstream control
line to the 1/2-inch NPT connection in either side of the
case body.

FL Series
5
Working Monitoring System Installation
Upsteamor Downstream Wide-OpenMonitoring System Installation
Single Pilot System Installation
Figure 3. Installation Drawings
A
4 x A
6 x A
TYPE PRX/120 OR
PRX/120-AP
TYPE SA/2 BLS
A
A
4 x A
6 x A
TYPE PRX/120 OR
PRX/120-AP TYPE PRX/120 OR
PRX/120-AP
TYPE SA/2 BLS
A
BLS
A
A
4 x A
6 x A
TYPE PRX/120 OR
PRX/120-AP
TYPE PRX/125 OR
PRX/125-AP TYPE PRX/120 OR
PRX/120-AP
TYPE SA/2
TYPE SA/2
BLS
A
BLS
A
BLS
A
E0825

FL Series
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9. Consulttheappropriate instruction manual for
installationofanoptional pneumatic or electric remote
control-driveunit. For optional remotepneumaticloading
of aTypePRX pilot, makethe springcase piping
connections just as they would be made for remote
venting.
Prestartup Considerations
Each regulator is factory-set for the outlet pressure
specified on the order. If no setting was specified,
outlet pressure was factory-set at the mid-range of the
pilot control spring. Before beginning the startup
procedure in this section, make sure the following
conditions are in effect:
• Blockvalves isolate the regulator
• Vent valvesare closed
• A bypass, if any, is in operation
In all cases, check the control spring setting to make
sure it is correct for the application.
Pilot supply pressure must be intro-
duced into the regulator before intro-
duction of any downstream pressure, or
internal damage may occur due to
reverse pressurization of the pilot and
main valve components.
Pressure gauges should always be used
to monitor downstream pressure during
startup. Procedures used in putting this
regulator into operation must be
planned accordingly if the downstream
system is pressurized by another regula-
tor or by a manual bypass.
Note
Pilot supply pressure must be at least 15
psig (1,0 bar) greater than control pres-
sure to operate the regulator at rated
travel.
Althoughremote loading or control constructions may
requireseparate adjustments on associated equipment,
the only adjustment normally necessary on a
Type FL-PRXregulator is the pressure settingof the
pilot control spring. Turning the adjusting screw
clockwise into the spring case increases the spring
compressionand pressure setting. Turning theadjust-
ing screw counterclockwise decreases the spring
compressionand pressure setting.
Pilot Adjustment
To adjust a standardType PRX pilot, loosen the
locknut, and turn the adjusting screw. Then tighten the
locknut to maintain the adjustment position.
Startup
1. Openthe upstream block(isolating) valve. Open
handvalveAinthe external pilot supply linebefore
openingthedownstreamisolatingvalve(seefigure3).
2. Openthedownstreamblock (isolating) valve for
minimumflow.
3. Slowlyopenhand valve B in thedownstream
control line, while at the same time adjusting the pilot
setting, if necessary.
4. Completelyopenthedownstream block valve.
5. Slowly close the bypass valve, if any.
Wide-Open Monitor Regulator
Installation
1. Forboththe wide-open monitoring regulator and
theworking regulator, perform the Single PilotRegula-
torInstallation procedures through step9.
2. Connect the control line of a wide-open monitoring
regulator(figure3)to downstream piping near the
workingregulator control line connection. During
normaloperationthewide-open monitoring regulator
standswide open with thepressure reduction being
taken across the working regulator. Only in case of
workingregulatorfailuredoesthewide-openmonitoring
regulator take control at its slightly higher setting.
Prestartup Considerations
Each regulator is factory-set for the outlet pressure
specified on the order. If no setting was specified,
outlet pressure was factory-set at the mid-range of the
pilot control spring. Before beginning the startup
procedures in this section, make sure the following
conditions are in effect:
• Blockvalves isolate the regulator
• Vent valvesare closed

FL Series
7
• Handvalvesareclosed
• A bypass, if any, is in operation
In all cases, check the control spring setting to make
sure it is correct for the application.
Introduce pilot supply pressure into the
regulator before introducing any down-
stream pressure, or internal damage
may occur due to reverse pressurization
of the pilot and main valve components.
Always use pressure gauges to monitor
downstream pressure during startup. If
the downstream is pressurized by
another regulator, plan startup proce-
dures accordingly.
Note
Pilot supply pressure must exceed
control pressure by at least 15 psig
(1,0 bar) in order to operate the regula-
tor at rated travel.
Althoughremote loading or control constructions may
requireseparate adjustments on associated equipment,
the only adjustment normally necessary on a
Type FL-PRXregulator is the pressure settingof the
pilot control spring. Turning the adjusting screw
clockwise into the spring case increases the spring
compressionand pressure setting. Turning theadjust-
ing screw counterclockwise decreases the spring
compressionand pressure setting.
Pilot Adjustment
To adjust a standardType PRX pilot, loosen the
locknut, and turn the adjusting screw. Then tighten the
locknut to maintain the adjustment position.
Startup
This procedure is to be repeated in turn for each
regulatorin the installation.
1. Slowlyopenthehandvalvein the pilot supply line.
2. Slowlyopentheupstreamblock(isolating) valve
and partially openthe downstream block valve for
minimumflow.
3. Slowly open the hand valve in the control line
while, at the same time, adjusting the pilot setting if
necessary.
4. Completelyopenthedownstream block valve.
5. Slowly close the bypass valve, if any.
Working Monitor Regulator
Installation
AllType FLworking monitor regulators are bench set at
thefactoryaccordingto the service conditions specified
onthecustomer’sorder. Examine the unit on arrival to
makesurenodamagehas occurred in shipment. Clean
and blow out pipelines to be sure no welding slag or
otherforeignmaterial is present.
Install theType FL into the pipeline using adequate
gasketsfor flanged regulator units and goodpiping
technique.Be sure to provide suitable pressuregauges
whereappropriate,blockvalves, bypass valves and
piping,and bleed valves to permitsafe and easy
maintenanceofboth the working monitor regulator and
thesecond-stage working regulator. Besure flow will be
in the direction indicated by the arrow cast on the body
Refer to the figure 3 schematic and figure 4, and
proceedin the following steps.
1. Attach the intermediate pressure control line
(1/2-inchNPT pipe) between the 1/2-inch NPT pipetee
andthe intermediate pressure portion of the down-
stream piping. Install hand valve B in this line.
2. Connect1/2-inchNPT distribution pressure
controlline piping between the 1/2-inchNPTconnec-
tion in the mounting bracket and the pipeline down-
streamofthe second-stageworkingregulator.Include
handvalveAin this control line.
Note
Each pilot has a nameplate identifying it
as the working or monitor pilot.
3. Pipe the pilot supply line to 1/4-inch NPT connec-
tion in the back of the working pilot body. Supply
pressure should be filtered if excess dirt or condensate
is present in the supply gas.
4. Installdownstreamworkingregulator per guide-
lines.

FL Series
8
Startup
1. Before introducing any pressure to the unit, close
handvalveAin the distributionpressurecontrollineand
hand valveB in the intermediatepressurecontrolline.
Pilot supply pressure must be intro-
duced into the regulator prior to intro-
duction of any downstream pressure or
internal damage may occur due to
reverse pressurization of the pilot and
main valve components. Pilot supply
pressure must be at least 15 psi (1,0 bar)
greater than control pressure for proper
operation.
2. Slowlyopenthehandvalvein the pilot supply line.
3. Slowlyopenthe upstream block valve and partially
openthedownstreamblockvalvefor minimum flow.
4. Slowlyopenhandvalve B and allow theintermedi-
ate pressure to increase to the working pilot setting.
5. Put the second-stage working regulator into
operationaccordingtorecommendedproceduresand
instructionsfurnished with the second-stage working
regulator.
6. After the distribution pressure has been estab-
lishedslowlyopen hand valveA.
Pilot Adjustment
Thesecond-stage working regulator must be set to
operate at a lower pressure than the monitoring pilot or
the monitoring pilot will try to take control of the
distribution pressure. Follow the steps listed to obtain
the desired results.
1. Increase the setting of the monitoring pilot by
loosening the locknut and turning the adjusting screw
clockwise (into the spring case cap) until the working
pilot is in control of the intermediate pressure and the
second-stageworking regulator is in control of the
distributionpressure.
2. Adjust the setting of the working pilot by loosen-
ing the jam nut and turning the adjusting screw clock-
wise (into the spring case cap) to increase the interme-
diatepressure, or counterclockwise (out of the spring
case cap) to reduce the intermediate pressure.Adjust
untildesired intermediate pressure is reached.
3. Adjust the second-stage working regulator to the
desireddistribution pressure by followinginstructions
forthatparticular regulator.
4. Adjust the setting of the monitoring pilot to
establishthe desired emergency distribution pressure,
which is to be maintained in the event of failure of the
second-stageworking regulator.The steps followed
may vary with each piping situation. The basic method
remains the same.
Thefollowingprocedureservesasanexample which
can be used or modified to make monitoring pilot
adjustments in any installation.
Increase the outlet pressure setting of the second-
stage working regulator until the monitoring pilot takes
control of the distribution pressure.Adjust the monitor-
ing pilot setting until the desired emergency distribution
pressureis achieved. Refer totable 2 for therecom-
mendedminimumdifferentialbetweenthemonitoring
pilot setting and the desired distribution pressure.
With settings as desired on both the monitoring and
the working pilots, tighten the locknuts to maintain
properadjustment screw positions. Then re-adjustthe
second-stageworking regulator to the desireddistribu-
tionpressure.
Shutdown
In any installation it is important to slowly open and
closethe valves and to ventthe outlet pressure before
ventingthe inlet pressure to prevent damagecausedby
reversepressurizationofthepilot or main valve.
Single Pilot Regulators and Wide-Open
Monitor Regulators
As well as applying to a single-pilot regulator, the steps
inthisprocedure also are valid for a wide-openmonitor-
inginstallation and should be repeated foreachregula-
tor in such an installation.
1. Closetheupstream isolating valve.
2. Close block valve Ain the supply line.
3. Closethedownstreamisolating valve.
4. If the downstream control line taps into the
pipeline above the downstream isolating valve,
openventvalveCbetweenthe regulator and the
downstreamisolating valve. Permit all pressureto
bleedout of the regulator.

FL Series
9
If the downstream control line taps into the pipe-
line below the downstream isolating valve, close
handvalveB. Then open vent valveCandventvalveD,
permittingall pressure to bleed out of theregulator.
5. Openventvalve E to release anyinlet pressure
that may be trapped in the regulator.
Working Monitor Regulators
1. Closetheupstream isolating valve.
2. Close hand valve in pilot supply line.
3. Closethedownstreamisolating valve.
4. Openableed valvebetweenthe second-stage
workingregulator andthedownstream isolatingvalve.
Permitallpressure to bleed out of theworkingmonitor
regulatorand thesecond-stageworking regulator.
5. Openventvalvetoventanyintermediatepressure
trapped in the system.
6. Openventvalveto release any inlet pressure
trappedinthe regulator.
Maintenance
Theregulatorparts are subject to normal wear and must
beinspected periodically and replaced as necessary.
Thefrequency ofinspectionandreplacement depends
ontheseverity of service conditionsandonapplicable
federal,stateandlocalcodes and regulations.
To avoid personal injury or property
damage from sudden release of pres-
sure, isolate the regulator from the
pressure system, and release all pressure
from the pilot and main valve before
performing maintenance operations.
MainValve
Main Valve Pad Replacement
1. Removeoutletflange (key 22) by removingsocket
head cap screws (key 5).
2. Removepadholder assembly and O-ring (key 18).
3. Removepad(key 20) from padholder (key 19) by
removingcap screw (key 25)and pad retainer (key 21),
replace pad if necessary.
4. Reinstall the pad.
Main Valve Diaphragm Maintenance
1. Place main valve with inlet side up.
2. Removethetravelindicatorassembly by removing
theindicator cover (key 40)and indicator bushing
(key 38). Check O-ring (key 37), replace if necessary.
Removethe indicator support (key36). Check O-ring
(key 35), replace if necessary. Lift out indicator stem
assembly (keys 33 and 34).
3. Removeinletflange (key 1) by removingsocket
head cap screws (key 5). Due to force created by the
spring(key 6), take care whenremoving inlet flange.
Check O-rings (keys 3 and 4) and anti-friction rings
(key 2), replace if necessary.
4. Lift out spring (key 6). Remove hex head cap
screws, washers, and nuts (keys 9, 14, and 15). Lift
off the inlet cover (key 11). Check O-ring (key 3) and
anti-friction rings (key 2), replace if necessary.
5. Removediaphargmassemblybyremovingscrews
(key 27) to separate the outlet and the inlet plates
(keys 12 and 8). Check diaphragm (key 10) and O-rings
(keys 26 and 28) for damage and replace if necessary.
Checksleeve (key 16) seating surfacefordamage.
6. Reassembleinreverseorder.
PRX Pilot Maintenance
Always remove spring (key 7) tension
before performing maintenance on this
unit. To remove spring tension, loosen
locknut (key 2) and back out adjusting
screw (key 1) until compression is
removed from the spring.
Lower Case Maintenance
1. Disconnect pilot and remove it from the line.
2. Removescrews(key10) from lower cover (key21)
andthe separate lower coverfrom the body (key 16).
3. Use a wrench to hold the stem (key 23) and break
loose the stem nut (key 20). Remove the stem nut and
washer(key 11).
4. Removethediaphragmplate (key 13), diaphragm
(key 14), pad holder (key 22), and O-ring (key 18).

FL Series
10
Inspectthe partsfor damage or wear, andreplace if
necessary.
5. Removeorifice(key 19) and O-ring (key17).
Inspectthe partsfor damage or wear, andreplace if
necessary. Lightly lubricate the O-ring and place in the
body (key 16). Install the orifice.
6. Set the pad holder (key 22) in the body (key 16).
7. Lightly lubricate the rims of the diaphragm (key 14)
and place it on top of the pad holder (key 22). Set the
diaphragmplate (key 13) onthe diaphragm (key 14).
8. Lightly lubricate the O-ring (key 18) and place it in
the lower case (key 21).
9. Place the washer (key 11) and stem nut (key 20)
on the stem (key 23) and tighten. If also performing
Upper Case Maintenance, skip to step 2 of the Upper
CaseMaintenance section.
10. Insert machine screws (key 10) in the lower cover
(key21) and tighten uniformly to ensure properseal.
Upper Case Maintenance
1. Disconnect pilot and remove it from the line.
2. Loosen locknut (key 2) and back out adjusting
screw (key 1) until compression is removed from the
spring. Remove cap (key 3).
3. Lift the spring carrier (key 6), spring (key 7), and
O-ring (key 4) out of the upper cover (key 8). Inspect
O-ringand replace if necessary.
4. Removemachinescrews (key 10) from lower cover
(key21) and the separate lower cover from the body
(key16),unlessremovedduringlowerdiaphragm
maintenance. Use a wrench to hold stem (key 19)
securely while removing the stem nut (key 26).
5. Removeremainingloosecomponents: washer,
upperdiaphragmplate, diaphragm, lower diaphragm
plate, and O-rings (keys 11, 13, 14, 15, 18, and 25).
InspectdiaphragmandO-ringsfor damage or wear, and
replaceif necessary.
6. Lightly lubricate the O-ring (key 25). Place O-ring
over the stem (key 19) and press it down into the body
(key 16).
7. Set the lower diaphragm plate (key 15) into the
body (key 16).
8. Lightly lubricate the rims of the diaphragm (key 14)
and place it in the body (key 16) on top of the lower
diaphragmplate (key 15).
9. Set the upper diaphragm plate (key 13) on top of
thediaphragm (key 14).
10. Place washer (key 11) and stem nut (key 26) on
the stem (key 19) and tighten using a wrench to hold
the stem.
11. Set the spring carrier (key 6).
Damper and Restrictor Maintenance
1. Remove screw (key 31) and plate (key 29).
2. Remove ring nuts (key 30).
3. Removedamper adjusting screw(key27). Remove
andinspect O-ring (key 28) for damage or wear, and
replaceif necessary. Lightly lubricateO-ring before
placing on the adjusting screw. Insert damper adjust-
ing screw into the body (key 16) and tighten. Insert
ring nut (key 30) and tighten. Back out damper
adjusting screw until it stops.
4. Removerestrictoradjusting screw with hole
(key 32). Remove and inspect O-ring (key 28) for
damage or wear, and replace if necessary. Lightly
lubricateO-ring before placing onthe adjusting screw.
Insert restrictor adjusting screw into the body (key 16)
and completely tighten. Insert ring nut (key 30) and
completely tighten. Back out restrictor adjusting screw
1/2 turn.
Note
When using a Type PRX/120 pilot with a
Type PRX/125 pilot as a monitor, use the
following settings:
• restrictor - completely tighten and
then back out three full turns.
• damper - back out until it stops.
5. Install plate (key 29) and screw (key 31).
Type SA/2
1. Disconnectpilotsupply filter regulator and remove
it from the line.
2. Removebolts, washers, andnuts(keys2, 9,and10)
frombody(key 16) and the separateupperandlower
covers (keys 11 and 19) from the body (key 16). When
separatingthe covers fromthebody,beawareof loose
components: (keys 1, 3, 4, 8, 12, 18, 20, and 21).
3. RemoveandinspectO-ring (key 13) for damage or
wear, and replace if necessary. Lightly lubricate the
O-ring before placing it back in the (key 11).

FL Series
11
4. Clean screens (key 8). Replace filter pad (key 12).
5. Inspectdiaphragm(key18) for damage or wear,
and replace if necessary. Check the seating surface of
the (key 17) for erosion, scratches, spurs, or other
damage,and replace if necessary.
6. Unscrew and remove (key 5). Inspect O-ring
(key6) for damage or wear, andreplace if necessary.
Lightly lubricate the O-ring and place it on (key 5).
7. Pull (key 15) out of the body (key 16). Inspect the
seat for damage, and replace if necessary.
8. Set the (key 15) on the spring (key 14) and insert
the (key 5). Tighten the (key 5) until it stops.
9. Lightly lubricate the outer and inner rims of the
diaphragm (key 18). Place the diaphragm assembly on
top of the (key 5). The (key 17) will slide into (key 5).
Usecare to avoid damage to parts when reassembling.
10. Set the spring (key 1) on top of the (key 21).
11. Align the (key 19) over the body (key 16) with the
sense port (V) opposite the pilot supply port (R).
12. Place the filter pad (key 12) and screens (key 8),
one on each side of the filter pad, on the (key 11).
13. Pick up the body (key 16) and place it on the
(key 11) with the inlet port (M) aligned vertically with the
sense port (V).
14. Insert bolts (key 2). Place washers (key 9) and
nuts (key 10) on the end of the bolts. Tighten the nuts.
Parts Ordering
Referto theType numberwhen contactingyourFisher
SalesOffice or Sales Representative for technical
information. When ordering parts, also be sure to
includethe complete 11-character partkit number.
Parts List
FL Main Valve (figure 4)
Key Description
Part Kit (includes key number: 2, 3, 4, 10, 18,
20, 26, 28, 35, 38, 46, and 47) See Table
1 Inlet Flange
2* Anti-Friction Ring
3* O-Ring
4* Body O-Ring
5 Screw
6 Spring
7 Fitting
8 Inlet Plate
9 Screw
10* Diaphragm
11 Inlet Cover
12 Outlet Plate
13 Outlet Cover
14 Washer
15 Nut
16 Sleeve
17 Fitting
18* O-Ring
19 Pad Holder
20* Pad
21 Pad Retainer
22 Outlet Flange
23 Gasket
24 Disassembly Spacer
25 Screw
26* O-Ring
27 Screw
28* O-Ring
29 Metal Plate
30 Nameplate Sticker
31 Drive Screw
32 Flow Arrow
33 Spring Collet
34 Indicator
35* O-Ring
36 Support
37 Indicator Bushing
38* O-Ring
39 Indicator Label
40 Indicator Cover
43 SR Silencer
46* O-Ring
47* O-Ring
48 Washer
* Indicates Recommended Spare.
1 (DN 25) 1-1/2 (DN 40) 2 (DN 25) 2-1/2 (DN 65) 3 (DN 80) 4 (DN 100) 6 (DN 150) 8 (DN 200)
NITRILE GD89984X012 GD89977X012 GD89985X012 GD89975X012 GD89986X012 GD89987X012 GD89988X012 ~
VITON GD89984X022 GD89977X022 GD89985X022 GD89975X022 GD89986X022 GD89987X022 GD89988X022 ~
NITRILE SR-SRS GD89973X012 GD89976X012 GD89972X012 GD89974X012 GD89971X012 GD89970X012 GD89969X012 ~
VITON SR-SRS GD89973X022 GD89976X022 GD89972X022 GD89974X022 GD89971X022 GD89970X022 GD89969X022 ~
SIZE, INCHES (DN)
MATERIAL
~CALL FOR KIT NUMBER
FL Series Parts Kit Part Numbers

FL Series
12
Figure 4. FL Assembly

FL Series
13
Figure 5. SRS Assembly
SRS Main Valve (figure 5)
Key Description
23 Gasket
24 Flange Spacer
200 Body
201 Retainer
202 Stud
203 Atenuator Plate
204 Spring Pin
205 Flange
206 Nut
207 Atenuator Plate
208 Atenuator Plate
209 Spacer
210 Spring Cage
211 Spring

FL Series
14
Figure 6. PRX Series Pilot Assembly
TYPE PRX/120 OR PRX/125
TYPE PRX/120-AP OR PRX/125-AP
TYPE PRX/120 OR PRX/125 TYPE PRX/120-AP OR PRX/125-AP

FL Series
15
PRX Series Pilots (figure 6)
Description Part Number
Elastomer Parts Kits (includes keys: 4, 5, 14, 17,
18, 25, and 28)
Types PRX/120 and PRX/125
Nitrile GD89982X012
Fluoroelastomer GD89982X022
Types PRX/120-AP and PRX/125-AP
Nitrile GD89982X012
Fluoroelastomer GD89982X022
Key Description
1 Adjusting Screw
2 Lockut
3 Cap
4(1) Upper Cover O-Ring
5(1) O-Ring
6 Spring Carrier Plate
7 Spring (See table 2)
8 Upper Cover
9 Spring Carrier Plate
10 Machine Screw
11 Washer
12 Filter
13 Diaphragm Plate
14(1) Diaphragm
15 Diaphragm Plate
16 Body
17(1) Orifice O-Ring
18(1) Lower Cover O-Ring
19 Orifice
20 Nut
21 Lower Cover
22 Pad Holder
23 Stem
24 Nameplate
26 Upper Diaphragm Nut
27 Damper Adjusting Screw
28(1) Restrictor/Damper O-Ring
29 Plate
30 Ring Nut
31 Damper/Restrictor Screw
32 Restrictor Adjusting Screw with Hole
33 Plug
34 Plug
Type SA/2 Pilot Supply Filter Regulator
(figure 7)
Description Part Number
Elastomer Parts Kits (includes keys: )
Nitrile GD89995X012
Fluoroelastomer GD89995X022
Key Description
1 Spring
2 Socket Head Cap Screw
3 Washer
4 Plate
5 Regulator Seat
6 O-ring
7 Body
8 Filter Net
9 Washer
10 Nut
Figure 7. Type SA/2 Assembly
1. Recommended Spare Part
Key Description
11 Filter Cover
12 Felt
13 O-Ring
14 Spring
15 Pad Holder Unit
16 Nameplate
17 Screw Unit
18 Diaphragm
19 Regulator Cover
20 Spring Washer
21 Nut

FL Series
Fisherisa markownedbyFisherControlsInternational,Inc.,a business ofEmersonProcessManagement. TheEmersonlogoisa trademarkandservicemarkofEmersonElectric Co. Allothermarksarethe
propertyoftheir respective owners.
The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not to be construed as warranties or guarantees, express
orimplied,regardingtheproductsorservicesdescribedhereinortheiruseorapplicability.Wereservetherighttomodifyorimprovethedesignsorspecificationsofsuchproductsatanytimewithoutnotice.
Fisherdoesnotassumeresponsibilityfortheselection, use or maintenance of any product. Responsibility for proper selection, use and maintenance of any Fisher product remains solelywiththepurchaser.
For information, contact Fisher:
Marshalltown, Iowa 50158 USA
McKinney, Texas 75070 USA
28320 Gallardon, France
40013 Castel Maggiore (BO), Italy
Sao Paulo 05424 Brazil
Singapore 128461
www.FISHERregulators.com
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