Brochure

From steam dilution to heat exchange, steam is an essential part of olen
production. The feedwater regulator control valve provides ow to the
boiler during normal plant operation when the boiler is under pressure.
During this time, the pressure drops are small and cavitation is not a
concern. Stable, reliable throttling is most important for efcient boiler
operation.
The feedwater startup and regulator applications are often combined
into one valve. Combined startup and regulation can eliminate cross-over
points and ease operation. During startup, the feedwater regulator control
valve experiences low ow rates with high differential pressure, which can
cause severe cavitation damage.
Boiler Feedwater Pump
Recirculation Valve
The boiler feedwater pump gets its feed from the deaerator at low
pressure, and discharges at high pressure above the main steam pressure.
During boiler startup or low load conditions, ow may not meet the
minimum requirements of the boiler feedpump.
The boiler feedwater pump recirculation valve protects the feedpump
by ensuring that adequate ow is passing through the pump at all times.
A modulating boiler feedwater pump recirculation valve provides an
efcient method to prevent cavitation from occurring in the pump. The
high pressure drops experienced by the recirculation valve can cause
severe cavitation that must be accounted for to ensure long valve trim life.
Cavitation abatement trim allows for protection over a range of conditions
from boiler startup to full load.
Boiler Feedwater Regulator and Startup Valve
10 | Fisher
®
Olefin Production Solutions
Emerson engineers conduct noise
and vibration tests on cavitating
applications in many different ways.
Transparent pipe allows visualization
of the cavitation field.
No cavitation.
Slight cavitation.
Full cavitation.