Startup, Adjustment and Shutdown
Note
The Specifications section and Table 1
provide the maximum pressure
capabilities for each regulator
construction. Use pressure gauges
to monitor inlet pressure and control
pressure during startup.
Startup
1. Slowly open the outlet block valve, if used, to
vapor recovery system and leave it fully open.
2.
Slowly open the shutoff valve (for Type T208M,
open the control line shutoff valve first followed by
the inlet shutoff valve) between the tank and vapor
recovery regulator.
3. Use gauges to monitor pressure.
Adjustment
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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
maintain a control pressure higher than
the upper limit of the control pressure
range for that particular spring. If the
desired control pressure is not within
the range of the spring, install a spring
of the proper range according to the
Diaphragm and Spring Case Area
section of the maintenance procedure.
Adjust the regulator control pressure setting to meet
the requirements of the specific application. The range
of allowable pressure setting is stamped on the
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 in the Maintenance section. To adjust
the pressure setting, perform the following steps
(key numbers are referenced in Figures 4, 5 and 6).
For internal flat circular adjusting screw
1. Remove the closing cap (key 22).
2.
Use a 1 in. / 25 mm hex rod or flat screwdriver
to turn the adjusting screw (key 35) 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. After making the adjustment, replace the closing
cap gasket (key 25) and install the closing cap
(key 22).
4. To remotely vent the regulator, remove the vent
assembly (key 26) and install obstruction-free
tubing or piping into the 1/4 NPT vent tapping.
Provide protection on a remote vent by installing
a screened vent cap into the remote end of the
vent pipe. If continuous operation of the system is
required during inspection or maintenance, install
a three-way bypass valve around the regulator.
5. The Type T208M requires a control line. Be sure to
install the control line before putting the regulator
into operation. Make the control line as short
and straight as possible and do not install it in a
location where flow may be turbulent. Significant
restrictions in the control line can prevent proper
pressure registration. When using a hand valve, it
should be a full flow valve, such as a full port ball
valve. Install the control line sloping downward
toward the tank to prevent condensation buildup
and avoid low points (or traps) that could catch
liquid. The sensing line must enter the tank
above the liquid level at a point that senses the
vapor space pressure and is free from turbulence
associated with tank nozzles or vents. The control
line pipe should be at least 1/2 in. / 13 mm in
diameter and increase 1 pipe size for every
10 ft. / 3.05 m of control line, with setpoint less
than 5 in. w.c / 12 mbar.
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 recovery regulators are not
intended to be used as an ASME certified relief
device for overpressure protection on a tank. They
are to be used as part of a gas blanketing system
to control outflow of blanketing gas under normal
conditions and collect tank vapors for the vapor
disposal reclamation system. Provide alternate
methods of emergency overpressure protection.
5
T208 Series
