Emerson FL, Инструкция по эксплуатации

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FL Series
6
9. Consult the appropriate instruction manual for
installation of an optional pneumatic or electric remote
control-drive unit. For optional remote pneumatic loading
of a Type PRX pilot, make the spring case 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:
• Block valves isolate the regulator
• Vent valves are 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.
Although remote loading or control constructions may
require separate adjustments on associated equipment,
the only adjustment normally necessary on a
Type FL-PRX regulator is the pressure setting of the
pilot control spring. Turning the adjusting screw
clockwise into the spring case increases the spring
compression and pressure setting. Turning the adjust-
ing screw counterclockwise decreases the spring
compression and pressure setting.
Pilot Adjustment
To adjust a standard Type PRX pilot, loosen the
locknut, and turn the adjusting screw. Then tighten the
locknut to maintain the adjustment position.
Startup
1. Open the upstream block (isolating) valve. Open
hand valve A in the external pilot supply line before
opening the downstream isolating valve (see figure 3).
2. Open the downstream block (isolating) valve for
minimum flow.
3. Slowly open hand valve B in the downstream
control line, while at the same time adjusting the pilot
setting, if necessary.
4. Completely open the downstream block valve.
5. Slowly close the bypass valve, if any.
Wide-Open Monitor Regulator
Installation
1. For both the wide-open monitoring regulator and
the working regulator, perform the Single Pilot Regula-
tor Installation procedures through step 9.
2. Connect the control line of a wide-open monitoring
regulator (figure 3) to downstream piping near the
working regulator control line connection. During
normal operation the wide-open monitoring regulator
stands wide open with the pressure reduction being
taken across the working regulator. Only in case of
working regulator failure does the wide-open monitoring
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:
• Block valves isolate the regulator
• Vent valves are closed