Taylor-Wharton EF-450 - Manual (Page 10)

Pressure Building Circuit
The pressure building circuit serves to build pressure after filling the vessel. The circuit is also used to ensure
sufficient driving pressure during high product withdrawal periods. Opening the pressure building circuit
valve (V-4) permits the circuit to function. A stainless steel tag labeled “P.B.” is attached to the valve. When
the pressure inside the vessel drops below the pressure builder setting, the pressure building stage of the
pressure building/economizer regulator (PCV-1) opens. This creates a path from the liquid in the bottom of
the container to the gas space in the top. This path contains an internal pressure building coil (PBC-1) to
vaporize product as it flows from the bottom to the top of the vessel. Liquid is expanded to a vapor and
pressure is increased in the vessel. The pressure building coil is attached to the inside surface of the vacuum
jacket.
V-4
PCV-1
Figure 4: Pressure building circuit highlighted in blue.
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