Because of their unique design characteristics,
RF Control Valves are recommended when...
abrasion and corrosion result in high maintenance,
turbulent flow causes valves or pipes to wear,
scaling causes valves to seize, and...
fibers or other materials have a tendency
to plug the valves.
RF Valves
serve as platforms for the most advanced analog and digital positioners
available in the marketplace today, including precision products from
industry leaders ranging from Fisher-Rosemount, ABB/Bailey, PosiFlex, Valtek,
and PMV to electro-mechanical multi-turn actuators from AUMA, Bernard, EIM,
Limitorque and Rotork. Inherently higher Cv values and the
ability to characterize valve ID to specific flow requirements are the
key factors resulting in more cost-effective throttling control for
slurry, sludge and liquids in industrial and municipal applications.
RF Control
Valve designs offer the flexibility to alter the elastomer tube
ID, or trim, as much as two standard sizes to optimize control valve
sizing and precision. This feature provides project and process
engineers with a built-in safety factor upon selecting a valve, where other
designs often require the selection of a larger less accurate valve size
to achieve the same end. Full- and reduced-port elastomer tube inserts
and a wide variety of elastomer qualities provide the most
advanced configurations for dealing with abrasive, corrosive, scaling
and plugging prone services, increasing wear life over conventional metal
and elastomer liner designs (selected profiles, below).
The
ability to offer full and reduced port valve trim allows each valve to
be precisely characterized to optimize flow control. Flexibility in
specifying RF Control Valve trim shape and ID results in more linear
flow characteristics and less turbulence than other valve types with
deflections, rubbing components, and poor shut-off that accelerates
wear.
Any RF Valve® can be made fully compatible with Hart®,
Modbus, Fieldbus™ and most other communication protocols through the use
of positioners offered by all the major instrument manufacturers. One of
the most affordable control valves in the marketplace today, the aiRFlex®
valve, is also operable with either an analog or digital signal in both
pressure and vacuum environments.
Utilizing the same elastomer tube technology
for full and reduced port configurations, aiRFlex® is
operated on plant air alone, eliminating the high cost and maintenance
associated with conventional pneumatic cylinder/positioner or
electro-mechanically actuated designs. A proportional pressure
controller is all that is required to achieve outstanding performance in
services where line pressure does not exceed 50 psi.
The inherently high Cv values of RF Control Valves ensure
superior cost-vs.-capacity ratios. Control performance is also enhanced,
as each valve is uniquely characterized to flow requirements with either
full- or reduced-port designs, thus reducing the turbulence and
cavitation found in other valve designs.
To examine the advantages of using pinch valves as
modulating valves, and RF Valves in particular, please go to
Control Valve Solutions.
