Taylor-Wharton High Capacity GST Storage Tanks - Manual (Page 24)

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SETTING PRESSURE BUILDING REGULATOR (PCV-1):
1.
If tank pressure is below desired setting: Loosen pressure screw locknut on PRESSURE
REGULATOR. With PRESSURE BUILDING ISOLATION VALVES open, gradually
open PRESSURE REGULATOR by turning pressure screw in (clockwise) to build tank
pressure to 5 psig (0.34 bar / 34 kPa) above the desired delivery pressure. Note that the
pressure screw must be adjusted in small increments, allowing sufficient time for tank
pressure to stabilize each time the screw is turned. When desired set point is reached,
tighten pressure screw locknut.
2.
If tank pressure is above desired setting: Loosen pressure screw locknut and turn pressure
screw out (counterclockwise) to end of adjustment range. Open TANK BLOWDOWN
VALVE and vent until tank pressure is 5 psig (0.34 bar / 34 kPa) above desired delivery
pressure. With PRESSURE BUILDING ISOLATION VALVES open, slowly turn pressure
screw in (clockwise) until PRESSURE REGULATOR just opens as indicated by cooling of
downstream pipe (at REGULATOR outlet). Tighten pressure screw locknut.
SETTING ECONOMIZER BACK PRESSURE REGULATOR:
1.
Loosen ECONOMIZER BACK PRESSURE REGULATOR pressure screw locknut and
turn pressure screw in (clockwise) to end of adjustment range. Check that the PRESSURE
BUILDING ISOLATION VALVES are open.
2.
a. If tank pressure is below desired set point: Build pressure by opening both fill
valves. Note that the fill connection must be securely blanked off. As tank pressure
increases to desired set point-- at least 10 psig (0.7 bar / 70 kPa) above setting of
PRESSURE BUILDING REGULATOR close BOTTOM FILL VALVE. When
liquid in line vaporizes, close the TOP FILL VALVE. Relieve any residual pressure
by momentarily opening FILL LINE DRAIN VALVE.
b. If tank pressure is above desired set point: Open TANK BLOWDOWN VALVE
and vent until tank pressure is at desired set point -- at least 10 psi (0.7 bar / 70 kPa)
above setting of PRESSURE BUILDING REGULATOR.
3.
With tank pressure at desired ECONOMIZER BACK PRESSURE REGULATOR set
point, slowly turn pressure screw out (counterclockwise) until valve just opens as indicated
by cooling of pipe between the ECONOMIZER BACK PRESSURE REGULATOR and
the ECONOMIZER ISOLATION VALVE.
INNER VESSEL AND PIPING SAFETY DEVICES
These tanks are equipped with a dual safety device manifold that permits servicing of one set of
safety devices while the other set is in service.
If a pressure vessel TANK RUPTURE DISC ruptures, determine and correct the cause of the
rupture before replacing the device. This device should be replaced annually as a preventive
maintenance procedure. The bursting disc on this tank is a sealed assembly that must be replaced as
a unit.