Type Y696
4
4. To remotely vent the regulator, remove the vent
(key 56) and install obstruction-free tubing or piping
into the 1/4 in. NPT vent tapping. Provide protection
on a remote vent by installing a screened vent cap
into the remote end of the vent pipe.
5. If continuous operation of the system is required
during inspection or maintenance, install a
three-valve bypass around the regulator.
6. Vapor recovery regulators are used to maintain
a constant inlet (blanket) pressure with the outlet
flowing to a system whose pressure is lower than
that at the inlet. The vapor recovery regulators
are not intended to be used as an ASME certified
relief device for overpressure protection. They
are to be used as part of a gas blanketing system
to control the outflow of blanketing gas under
normal conditions and to collect tank vapors for
the vapor disposal or reclamation system. You
should provide alternate methods of emergency
overpressure protection.
Startup and Adjustment
!
WARnIng
To avoid personal injury, property
damage or equipment damage caused
by bursting of pressure containing
parts or explosion of accumulated
gas, never adjust the control spring to
produce an outlet pressure higher than
the upper limit of the outlet pressure
range of that particular spring. If the
desired outlet pressure is not within
the range of the control spring, install
a spring of the proper range according
to the Diaphragm and Spring case Area
section of the maintenance procedure.
With installation completed, the regulator can be
placed in operation by slowly opening the upstream
and downstream block valves, if used, while using
gauges to monitor pressure.
The regulator has been adjusted at the factory to
provide approximately the pressure requested. The
range of allowable pressure settings is stamped on the
spring casing nameplate. If a pressure setting beyond
the stamped range is required, install a spring with the
desired range by following the procedures for changing
the spring and diaphragm in the Maintenance section.
To adjust the pressure setting, perform the following
steps (key numbers are referenced in Figure 3):
1. Remove the closing cap (key 3).
2. Turn the adjusting screw (key 2) either clockwise
to increase control pressure or counterclockwise to
decrease control pressure. The regulator will go into
immediate operation. To ensure correct operation
always use a pressure gauge to monitor the vapor
recovery pressure when making adjustments.
3. Replace the closing cap (key 3).
Shutdown
First close the nearest upstream shutoff valve and
then close the nearest downstream shutoff valve to
vent the equipment properly. Next, open the vent
valves on both the upstream and downstream sides of
the regulator. All pressure between the shutoff valves
is released through the open vent valves.
Maintenance
Regulator parts are subject to normal wear and
must be inspected and replaced as necessary. The
frequency of inspection and replacement of parts
depends upon the severity of service conditions
or the requirements of local, state and federal
regulations. Due to the care Emerson™ takes in
meeting all manufacturing requirements (heat treating,
dimensional tolerances, etc.), use only replacement
parts manufactured or furnished by Fisher.
Key numbers are referenced in Figure 3.
!
WARnIng
To avoid personal injury, property damage
or equipment damage caused by sudden
release of pressure, isolate the regulator
from all pressure and cautiously release
trapped pressure from the regulator
before attempting disassembly.
Body Area
This procedure is for gaining access to the disk
assembly, orifice, body gasket and split ring. All
pressure must be released from the regulator, before
the following steps can be performed.
