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eplugTMRotary Valves
Technology and Innovation in Process Control
Characteristics of the EccentricRotary Plug Valve include:
� Minimal seat wear due to the cam action of
the plug� Low operating torque due both to the aerodynamic
shape of the plug and to its minimum contact with
the valve seat� An inherent, approximately linear or equal % flow
characteristic� Low-friction design� Wide choice of construction options for general
service to severe service applications
Technology and Innovation in Process Control
Combining Flow Control Technology with Economy to Provide the Right Valve... at the Right Price... for the RightResults.
eplug�
Rotary Valves
ou may have heard of the advantages given by rotary control valves. These
advantages include greater flow capacities, higher rangeabilities, compact
overall sizes, superior shaft sealing, and being applicable to a wider range of control
situations.
Introducing the Fisher eplug family of eccentric-action rotary plug valves that offer
even more advantages. They�re designed for process applications, built tough for
control, and intended for performance-demanding situations. Which means you get
unmatched flow control value, right from the start.
A Choice of Performance Capabilities
We�ve included a trio of valve designs within the eplug family. One provides accurate
flow control over a wide range of general service conditions. The second, in addition
to offering accurate control, also gives you the ability to win against mild to severe
erosive liquids as well as other hard-to-handle fluids. The third offers enhanced control
performance with greater capacity and rangeability. Each design offers distinct
control capabilities and advantages that let you select the valve that�s best matched
to a given application.
Y Eccentric Rotary Plug Valve: A rotary
control valve in which a plug-shaped
(versus full or partial ball) flow-restricting
member rotates through a 60° or 90° arc
to move from a closed to a full-open
position. The centerline of the plug is offset
from that of the valve shaft, which causes
the plug to follow an eccentric path as it
rotates. The result is that the plug has no
contact with its seat until it turns to within
a few degrees of the shutoff position.
As the plug contacts or �cams� into the
seat, the seating surfaces dynamically align
to achieve shutoff.
Stepped Seat
Eccentric Plug
Technology and Innovation in Process Control
When dealing with liquidflow, the BV500 valve�sstepped seat design stages the pressure drop when the valve is nearly closed.This pressure staging greatly reduces the cavitation potential and helps avoid seat damage.
The BV500 meets high flow requirements, and its aerodynamically contouredplug eliminates flow-induced torque reversals to allow use of smaller actuators for greater economy.
A Design for General Service
Excessive aerodynamic noise is yetanother problem solved by the BV500,thanks to its unique attenuator disc.The disc fits within the body outlet to quiet valve operation by as much as 10 dBA versus unattenuated valve designs.
For Control Over a Wide Range of ServiceConditions, Specify the Design BV500
The Design BV500 rotary plug valve gives accuratethrottling control of liquids and gases over a widerange of industrial applications. Compact andrugged in design, the BV500 combines astreamlined flow passage and tough metal trim components into an efficient and effective control package.
The BV500 is lighter in weight and more compactthan many rotary plug valves, which means easierhandling during installation and maintenance procedures.
With its ability to handle a wide number ofapplications, the BV500 helps you reduce the timespent in valve selection, lets your plant techniciansbecome familiar with its operation quickly and easily, and significantly reduces your parts inventory needs.
The BV500, with its many flow controladvantages, gives you a single valve that you canuse effectively over a majority of your generalservice flow applications.
The gasketed seatring prevents wiredraw erosionbetween valve bodyand seat ring.
Technology and Innovation in Process Control
A petrochemical plant in Europe utilized a rotary plug valve to control toluene liquid at
a pressure drop of 14.6 bar and a temperature of 175°C (347°F). The valve
experienced cavitation and flashing at 15% to 20% open, along with
performance-robbing vibration.
The solution to this two-pronged problem was to install a Fisher eccentric
rotary plug valve equipped with an attenuator disc. Immediately upon
startup, the new valve�s operation was noted to be smooth and stable
without any signs of cavitation or flashing. After three months of
uninterrupted service with the Fisher valve, the plant operator installed two
additional eccentric rotary plug valves to replace troublesome valves that
were controlling similar flow conditions.
A Case-In-Point
The true measure of a quality control valve is derived from its ability to reduceprocess variability during closed loop control. During performance testing, theBV500 control valve assembly demonstrated exceptional performance over theentire range of controller tunings. Notice how the BV500 control valve assemblyclosely follows the Ideal Control Loop Curve. The BV500 proved superior tocompetitive brand eccentric rotary plug valves in similar tests.
Technology and Innovation in Process Control
Reverse Flow AdvantageFor erosive applications, therecommended flow direction for theV500 is with the shaft upstream. Thehighest velocity flow is isolated inthe port or outlet area where theseat and retainer can be protectedby utilizing more erosion-resistantmaterials.
Erosion Fighter: The Design V500 - A long-timerotary valve favorite known for its ability to fightoff the effects of erosive slurries, coking, as well asother tough-to-control abrasive fluids.
The Fisher V500 can be configured to match thetoughest of erosive applications with its massiveshaft and bearing designs, streamlined flowcontouring and choice of erosion fighting trimmaterials. A sealed bearing design is also availablefor abrasive flows to combat any potential for shaftseizure. The V500 outpaces competitive offeringsin solving some of the most arduous controlapplications.
A Design for Control of Tough Fluids
Materials that MatchA choice of trim materials helps in matching the V500 to theprocess. A ceramic V500 plug, seatring, and retainer, for example, offer superior erosion resistance.
Technology and Innovation in Process Control
A Canadian paper mill experienced continual control and shutoff problems with the
main, white-liquor control valve on its digester. White liquor tends to precipitate minerals
out of water, which is a phenomenon called scaling. The full ball-style
valve used by the mill for white liquor control proved especially vulnerable
to scaling due to its ball and seal design. Scale would build up between
the body and ball, as well as in areas of static or low flow within the body,
and eventually the ball would seize.
With the valve literally stuck in one position, pulp production became
limited. Mill personnel attempted to avoid this situation by removing the
valve, acid washing its trim and internal passages, and then reinstalling
the valve. This occurred every three months, and the procedure required
24 hours each time.
A V500 equipped with a FIELDVUE® Digital Valve Controller was installed
as a solution. The self-lapping action of the eccentric plug, together with
the inherent, dual flow path above and below the plug (see illustration)
practically eliminated scale buildup. Extra maintenance time was
eliminated as was lost production.
After one year of continuous operation, the V500 was providing
accurate control and tight shutoff, all without the need for maintenance
and without having to limit production.
A Case-In-Point
Accuracy in Control Splined and clamped connectionbetween actuator lever and valve shaft helps ensure accurate plug positioning for high-performance control.
Long Life, Bi-Directional SeatingBoth sides of the patented seat ring
have a shutoff surface, which meansthe ring can be flipped over to extend
its operating life. The seat ring self-centers, self-laps, and dynamically
aligns with the plug to give ANSI ClassIV shutoff in either flow direction.
Technology and Innovation in Process Control
A Design for Enhanced Throttling Performance
The Design CV500 - Offers greater capacity thanother eccentric-action rotary valves, thanks to itsunrestricted, straight-through flow path. Plus, its V-notch ball creates an inherently equal percentflow characteristic. Bi-directional sealing extendsits application range.
The CV500 valve is making its mark as one of thepremier performers in reducing process variabilitywith a measured deadband of less than 0.2%. Also, with its rugged shaft, bearing and seatdesigns, the CV500 is finding extensive use in thetough control applications that require precision,such as on batch digesters within the Pulp & Paperindustry, against heavy scaling services inHydrocarbon processes, as well as on gas turbinesin the Power industry.
The inherent flow characteristic of the CV500 is approximately
equal %. This, along with its unrestricted flow path and
patented ball contour, offers greater flow rangeability and
a broader control range than that of most other eccentric
plug valve designs.
Technology and Innovation in Process Control
Fisher adds to the value offered by each member of theeplug valve family through these performance features:
� Accurate Flow Control - High-strength, splined and clamped shafts resist torsion forces in high-pressure conditions to give exact plug positioning.
� Economy in Actuation - The engineered contours of the rotary plug streamline the flow pattern through the valve, reducing operating torque to allow use of smaller and more economical actuators.
� Digital Control Capability - Each eplug valve can be equipped with the industry�s most widely applied digital valve instrument, the FIELDVUE® Digital Valve Controller.
� Process Compatibility - Trim material options are available to give extra protection depending on the application. Optional materials for sour fluids and gases meet the recommendations of the National Association of Corrosion Engineers (NACE) MR0175.
� Structural Integrity - One-piece body construction improves structural integrity of the pressure boundary by eliminating the potential leak paths found in two-piece, bolted valve designs.
� Meets Installation Needs - Integral valve body flanges promote secure valve installation and piping integrity.
� Complies with Environmental Standards - ENVIRO-SEAL® shaft packing option routinely meets strict emission requirements, such as the U.S. Clean Air Act limit of 500 parts-per-million. It is also field-proven to give extended service life.
� Integral Positioner Mounting - Eliminates the need for brackets and couplings and provides direct feedback of shaft rotation for zero backlash and improved performance.
Added-Value Features
A choice of Fisher pneumatically operatedrotary actuators makes it easy to specify theright eplug control valve package for eachapplication. The rotary actuators, available inspring-and-diaphragm and piston styles, sharedesign and construction features that ensureefficient and stable valve operation, evenunder application extremes.
� All actuator/positioner/valve linkages are enclosed for both personnel safety and protection against damage.
� Actuator housings are rugged to meet repeated, high-torque requirements.
� Splined-and-clamped valve shaft lever, plus a single-point actuator rod connection,
minimize lost motion for maximum throttling control accuracy.
� A selection of actuator sizes allows matching actuator output to operating torque requirements.
For Even Greater Versatility, Specify Fisher Valve Positioners
While the rotary actuators, alone, provideeither on-off or throttling control, the additionof a pneumatic or current-to-pneumaticpositioner provides even greater controlflexibility. Designed specifically for Fisherrotary valves, these positioners give fast,accurate response to input signals receivedfrom pneumatic or electronic control devices.Operating settings can be changed quicklyand easily to fine-tune positioner action.
FIELDVUE® Digital Valve Controllers �Capabilities That Extend Beyond Traditional Valve Control
While a traditional valve positioner serves asingle purpose, which is to maintain a valve inits intended control position, FIELDVUE digitalvalve controllers provide much more.FIELDVUE instrumentation collects real-timedata about valve performance, which provescrucial not only to reducing process variabilitybut also to enhancing plant operations.
Expert Application Assistance FromThe Application Experts
In the battle for performance and production,you need every advantage you can get. Fromapplication expertise to training to quickreplacement parts to valve repairs, you canalways count on Fisher for quality, service and expertise.
The next time you need to specify a controlvalve for your system, whether for generalservice or severe, consider the eplug. Contactyour Emerson sales office or sales representativelocation where highly skilled and experiencedapplications personnel are ready to help youtake advantage of the many benefits ofthe Fisher eplug family of rotary valves.
Choose the Actuator and Accessories to Fit the Control Situation
Pneumatically operated diaphragm actuators allow efficient on/off or throttling control with a built-in, fail-safe feature.
Pneumatically operated pistonactuators give powerful two-position or throttling control.
Technology and Innovation in Process Control
If you like the advantages of rotary valve control, then you�ll truly appreciate the added control valve value brought by the Fisher eplug designs. Here is a brief rundown of design specifications to help you select the best eplug valvefor your application:
Heavy-Duty, Erosive Service Valve -The V500Sizes: 1, 1-1/2, 2, 3, 4, 6 and 8 inch (DN sizes 25, 40, 50, 80, 100, 150, 200)End Connection & Ratings: Raised-face or ring-type-joint flanges;
ANSI Class 150, 300 or 600 (DIN PN 10, 16, 25, 40, 63, 100)Shutoff Classification: Class IV per ANSI/FCI 70.2 and IEC 60534 - 4Flow Characteristic: Modified linearFlow Coefficients: See Table 1Flow Coefficient Ratio: 100 to 1Valve Plug Rotation: 90 degreesShaft Packing: Standard is PTFE; Optional includes ENVIRO-SEAL PTFE or graphite
Complete specifications can be found in Fisher Bulletin 51.3:V500.
High-Capacity, High-Performance Valve - The CV500Sizes: 3, 4, 6, 8, 10 and 12 inch (DN sizes 80, 100, 150, 200, 250, 300)End Connection & Ratings: Raised-face or ring-type-joint flanges;
ANSI Class 150, 300 or 600 (DIN PN 10, 16, 25, 40, 63, 100)Shutoff Classification: Class IVFlow Characteristic: Approximately equal percentageFlow Coefficients: See Table 1Flow Coefficient Ratio: 200 to 1Valve Plug Rotation: 90 degreesShaft Packing: Standard is PTFE; Optional includes ENVIRO-SEAL PTFE or graphite
Complete specifications can be found in Fisher Bulletin 51.3:CV500.
Economical, General Service Valve - The BV500Sizes: 1, 1-1/2, 2, 3, 4 and 6 inch (DN sizes 25, 40, 50, 80, 100 and 150)End Connection & Ratings: Raised-face flanges in ANSI Class 150 and 300
(DIN PN 10, 16, 25 and 40)Shutoff Classification: PTFE seat, Class VI; metal seat, Class IVFlow Characteristic: Modified linearFlow Coefficients: See Table 1Flow Coefficient Ratio: 100 to 1Valve Plug Rotation: 60 degreesShaft Packing: Standard is PTFE; Optional includes ENVIRO-SEAL PTFE or graphite
Complete specifications can be found in Fisher Bulletin 51.3:BV500.
Added Value for Your Control Valve Dollar
Table 2. Fluid Compatibility Guidelines
Nature of Fluid
Valve Clean Dirty Viscous Corrosive Erosive Fibrous Design Slurry
V500 A A B A A C
CV500 A B A B B B
BV500 A B C C C C
A = Best choice. Highly suited to this type of service.B = Good choice. May require use of options for enhanced performance.C = Not recommended for this service.
Technology and Innovation in Process Control
Table 1. Sizing Coefficient at Maximum Rotation
Valve Design V500 CV500 BV500
Valve Size Sizing Coefficient Cv
1" (DN 25) 16.8 � 14
1-1/2" (DN 40) 31 � 30
2" (DN 50) 57.4 � 45
3" (DN 80) 141 166 107
4" (DN 100) 235 346 195
6" (DN 150) 717 809 410
8" (DN 200) 986 1440 �
10" (DN 250) � 2360 �
12" (DN 300) � 3050 �
BV500V500CV500
© Fisher Controls International, Inc. 2001 All Rights Reserved.
Fisher, Emerson Process Management, eplug, FIELDVUE and ENVIRO-SEAL are marks of one of the Emerson Process Management family of companies. The Emersonlogo is a trademark and service mark of Emerson Electric Co. All other marks are the property of their respective owners.
The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy they are notto be construed as warranties or guarantees, expressed or implied, regarding the products or services described herein or their use or applicability. All salesare governed by our terms and conditions, which are available upon request. We reserve the right to modify or improve the designs or specifications ofsuch products at any time without notice.
Emerson Process Management Fisher Controls International, Inc.205 South Center StreetMarshalltown, Iowa 50158T 1 (641) 754-3011F 1 (641) 754-2830www.EmersonProcess.com/Fisher
D350825X012 Printed in U.S.A. / 15M / 11-01
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