Emerson V150E Manual do Utilizador

CONTROL VALVE SOURCEBOOKPULP & PAPER

1−2Valve Types and CharacteristicsThe control valve regulates the rate of fluid flow asthe position of the valve plug or disk is changed byforce from

7−10and pressure as well as the position of the valve.Upstream and spraywater enthalpies are thendetermined using an inherent steam table withinthe DC

7−11Figure 7-12. Turbine Bypass SystemE0866the latest technology in pressure-reducing/lownoise trim to handle the flow and reduction ofpressure energ

7−12Control of the HP bypass is normally initiated viafeedback input signals from the main steampressure and the cold reheat temperature. Theratio of

7−13alternatives are also available for the TBX sparger(figure 7-13).Control of the HRH and LP bypass valvesnormally is initiated via feedback input s

7−14This is important in the production of steam puritybefore the turbine start. Steam flow through thesuperheater and reheater enhances the tubecool

www.Fisher.comChapter 8Process OverviewThe modern pulp and paper mill is a complexmanufacturing process involving many variedtypes of operation. Many

8−2sodium hydroxide (NaOH) and sodium sulfide(Na2S). This solution, known as white liquor,breaks down the glue-like lignin which binds thecellulose wo

8−3BurningBlack liquor from the evaporators at 50 - 55%solids cannot be burned in the recovery boiler.Further evaporation to 65 - 70% solids must beat

8−4totally enclosed pressure diffusion washersfollowing O2 delignification to further reduce toxiceffluent.Another change involves increased substitut

8−5pumped through screens and cleaners to the headbox. Screen and cleaners remove undesirableparticles such as dirt, grit and clumps of fibers, orchem

1−3Figure 1-2. Flanged Angle-StyleControl Valve BodyW0971Figure 1-3. Bar Stock Valve BodyW9756cage-guided trim, bolted body-to-bonnetconnection, and o

8−6tie is usually established with the local utility. Thisalso allows the mill to remain in operation if theirelectrical production is curtailed or do

8−7C0810 / ILFigure 8-1. Kraft Pulp and Paper Mill Process Overview

8−8C0811 / ILFigure 8-2. Kraft Recovery Cycle

8−9C0812 / ILFigure 8-3. Utilities

8−10

www.Fisher.comChapter 9PulpingPulping is the process of converting wood materialto separate pulp fibers for paper making.Processes range from purely m

9−2E1387PRESTEAMERCHIPSFRESH STEAMPCV-2TMP PULPPCV-3REFINERCYCLONESTEAM TOSTACKPCV-1PCV-4PROCESSSTEAMSTEAM TORECOVERYFigure 9-1. Thermomechanical Pu

9−3Chemical PulpingChemical pulp is produced by combining woodchips and chemicals in large pressure vesselsknown as digesters (see chapter 3) where he

9−4binds the cellulose wood fibers together. Thisprocess produces stronger pulp than the otherprocesses, but is darker in color than the otherpulp pro

www.Fisher.comChapter 10ADigestersBatch Digesters – Kraft PulpingKraft batch digesters have been produced inseveral different configurations, includin

1−4Figure 1-6. High Capacity Valve Body withCage-Style Noise Abatement TrimW0997Downstream pressure acts upon both the top andbottom sides of the valv

10A −2Figure 10A-1. Directly Steamed Batch Digester

10A −3Figure 10A-2. Indirectly Steamed Batch Digester

10A −4dry wood. However, these total liquor-to-wood andliquor-strength-to-wood ratios are difficult toenforce because on-line measurement of chipmoist

10A −5Figure 10A-5. Steam Demand ProfileFigure 10A-4. Actual Batch Cooking CycleFigure 10A-3. Theoretical Batch Cooking Cycle

10A −6False PressureA batch digester is basically a large pressurecooker. As steam is applied to the mass of chipsand liquor, a quantity of resinous v

10A −7withstand digester-like pressures and so the reliefvalve will pop if the outlet for gas-off is pluggedwith pulp. Similarly, flashed vapor to a c

10A −8Batch Digester – Low EnergyProcessMuch has been written about the relatively newlow energy cooking process. Studies indicateimproved pulping pro

10A −9Figure 10A-6. Typical Three-Stage Design

10A −10Control Valve SelectionGeneral Service ValvesRefer to figure 10A-6.PROCESS FISHER CONTROL VALVE PRODUCT DESIGNValveTag #WARM BLACK LIQUORACCUMU

10A −11Refer to figure 10A-6.PROCESS FISHER CONTROL VALVE PRODUCT DESIGNValveTag #DIGESTERV150 V200 V300 V500 CV500 A81Control-DiskED/ETTypicalValveSi

1−5Figure 1-7. Three Way Valve withBalanced Valve PlugW9045-1Figure 1-8. High-Performance ButterflyControl ValveW4641for throttling service or for on-

10A −12

www.Fisher.comChapter 10BKamyrR Continuous DigestersKamyrR continuous digesters vary dependingupon the type of raw material, end product, thecost of c

10B −2mass throughout the chip column which explains agrowing use of the two vessel digester system.ProcessRegardless of the type, a Kamyr continuousd

10B −3Figure 10B-1. Chip FeedingE1214speed drive on the chip meter drive. It is importantto keep the chip meter full in order to maintain asteady feed

10B −4Figure 10B-2. Steaming VesselE1215— dP = 50 – 60 psid— Q = 2900 – 5000 lbs/hrD Typical valve selection:— This is specified by Kamyr as a NPS 8 t

10B −5chip chute is maintained at a constant level by theuse of a level control valve on the overflow line,which carries excess liquor to a surge tank

10B −6Figure 10B-3. Cooking Flow Diagrampressure control valve. Two large piston-operatedvalves are designed to isolate the top circulationline from t

10B −7— T = 190_F— P = 240 psig – 280 psig— dP = 75 psi – 110 psi— Q= 50-125 gpmD Typical valve selection:— NPS 2 to NPS 3 valves with alloy 6scraper

10B −8— dP = 42 psiD Typical valve selection:— In cases where entrained particles arefound in the flow, the recommended valve isa CV500 with hardened

10B −9D Typical process conditions:— Fluid: White liquor— T = 190_F— P = 260 psig – 280 psig— dP = 35 psi – 60 psi— Q = 200 – 900 gpmD Typical valve s

1−6Figure 1-10. Fisher Control-Disk Valve with 2052 Actuator and FIELDVUE DVC6200 Digital Valve ControllerW9425 W9418WAFER STYLE SINGLE FLANGE STYLED

10B −10impregnation vessel to raise the temperature ofchips and liquor going to the digester.D Typical process conditions:— Fluid: Black liquor— T = 3

10B −11— Q = 9000 gpmD Typical valve selection:— This valve is specified as a full bore ballvalve by Kamyr, and is referred to as theRO1 valve. It is

10B −12— Q = 500 gpmD Typical valve selection:— Kamyr has specified a V150 Vee-Ballvalve, NPS 2 – NPS 3 size, with stainlesssteel body and ball, Nitro

10B −13and flows to the outer shell equally in alldirections.Chips continue down the digester for a shortdistance into the lower cooking zone, where a

10B −14shaft and no seal. Used in conjunction withthe 1061 actuator with a quad seal option,this assembly is capable of a relatively longlife in this

10B −15— P = 170 psig 10— dP = 170 psiD Typical valve selection:— These are typically in the NPS 8 sizerange for KV-19 A, B, C, D and in the NPS 3size

10B −16Valve: KV-16A-D Digester extractionswitching valvesThese valves provide screened liquor extractionfrom the upper wash zone of the digester. Thi

10B −17D Typical process conditions:— Fluid: Black liquor— T = 260_F— P = 185 – 195 psig— dP = 185 – 195 psi— Q = 1500 gpmD Typical valve selection:—

10B −18pulp. The pressure drop is from digester pressureto atmospheric in the blow tank.As in the top circulation line, there are twoisolation valves

10B −19valves are on/off valves but are usuallyequipped with positioners so that they can beused as backup flow control valves.Control Valve Selection

1−7Figure 1-12. Sectional of Eccentric-PlugControl Valve BodyW4170-4D They utilize standard diaphragm or pistonrotary actuators.D Ball remains in cont

10B −20KAMYRTAG#KAMYR CONTINUOUS DIGESTERFISHER CONTROL VALVEPRODUCT DESIGNApplication DescriptionControlFunctionV150 V200 V300 V500 CV500 8580Typical

10B −21KAMYRTAG#KAMYR CONTINUOUS DIGESTERFISHER CONTROL VALVEPRODUCT DESIGNApplication DescriptionControlFunctionV150 V200 V300 V500 CV500 8580Typical

10B −22KAMYRTAG#KAMYR CONTINUOUS DIGESTERFISHER CONTROL VALVEPRODUCT DESIGNApplication DescriptionControlFunctionV150 V200 V300 V500 CV500 DSV 8580Typ

10B −23KAMYRTAG#KAMYR CONTINUOUS DIGESTERFISHER CONTROL VALVEPRODUCT DESIGNApplication DescriptionControlFunctionV150 V200 V300 V500 CV500 DSV 8580Typ

10B −24KAMYRTAG#KAMYR CONTINUOUS DIGESTERFISHER CONTROL VALVEPRODUCT DESIGNApplication DescriptionControlFunctionV150 V200 V300 V500 CV500 8580 EZTypi

www.Fisher.comChapter 11Black Liquor Evaporator & ConcentratorThe evaporator/concentrator system serves as abridge between the pulp mill and power

11−2E0894Figure 11−1. Multiple-Effect Evaporator Six Effect / Rising Film / LTV

11−3below the lower tube sheet. As it boils orpercolates, a thin film of liquor rises up the insideof the tube or plate. The liquor overflows the uppe

11−4Figure 11-2. Falling Film ConcentratorE0895Foul condensates are formed in both theevaporators and digesters. The primary reason forstripping foul

11−5today’s concentrator, it was often referred as adirect contact evaporator. The two most widelyused types, the cyclone and cascade evaporators,util

1−8Figure 1-13. Popular Varieties ofBolted Flange ConnectionsA7098Figure 1-14. Common Welded End ConnectionsA7099finished with concentric circular gro

11−6ValveTag #EVAPORATORS/CONCENTRATORS FISHER CONTROLS VALVE PRODUCT DESIGNApplication DescriptionControlFunctionV150 V5008580/Control-DiskA81 E−Body

www.Fisher.comChapter 12Kraft Recovery Boiler − Black Liquor SystemThe kraft recovery boiler is the heart of a complexseries of chemical processes ref

12−2Two components commonly employed on older, orconventional boilers, are direct contactevaporators and black liquor oxidation systems.Direct contact

12−3magnetic flow meters. If solids drop below 60%,auxiliary fuel is added due to the potential of asmelt/water explosion or bed “blackout”. If solids

12−4tolerated as a leak could result. A cleaningprocess for the boiler tubes is needed even whilethe boiler is in operation. This process is calledsoo

12−5Typical Specification:ES flow-down for on/off sootblowers.To conserve energy, mills have moved tothrottling sootblower valves. Use an ED.Tight shu

12−6Table 12-1. Kraft Recovery Boiler / Black Liquor System Valve SelectionPROCESS FISHER VALVE PRODUCT DESIGNValveTagKraft Recovery Boiler / Black Li

12−7E0893Figure 12-1. Kraft Recovery Boiler Black Liquor System

12−8

www.Fisher.comChapter 13Recausticizing and Lime RecoveryThe recausticizing and lime recovery plant is thefinal step in the Kraft recovery process. It

1−9Figure 1-15. Typical Bonnet, Flange,and Stud BoltsW0989On a typical globe-style control valve body, thebonnet is made of the same material as the v

13−2mud is admitted to precoat the outside of the filter.A vacuum is maintained on the inside of the filterwith a vacuum pump. The dregs slurry is pul

13−3operation and efficiency of the lime kiln.An accurate and reliable control valve isrequired for optimum performance.— The underflow valve must bea

13−4fresh water spray may also be used for furtherwashing of cooking chemicals from the lime mud.The dewatered lime mud is removed with ascraper blade

13−5C0814 / ILFigure 13-1. Recausticizing and Lime Recovery

13−6Figure 13- 2. White Liquor and Lime Mud Pressure FiltersC0813 / IL

13−7Control Valve SelectionPROCESS FISHER VALVE PRODUCT DESIGNValveTag #Recausticizing and Lime RecoveryV150/V300V500Control-DiskA81 E−BodyTypicalValv

13−8

www.Fisher.comChapter 14Bleaching and BrighteningBleaching and BrighteningIf the kraft pulp being produced is going to bebleached, then pulping is all

14−2of the remaining lignin can be removed; furtherdelignification would cause excessive cellulosedegradation. Lignin removal in oxygendelignification

14−3Figure 14-2. Conventional Bleaching ProcessDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.alternating pattern of

1−10Figure 1-16. Extension BonnetW0667-2Figure 1-17. Valve Body withFabricated Extension BonnetW1416carbon steel because of its lower coefficient ofth

14−4Figure 14-3. Chlorine Dioxide (ClO2) Filtrate FlowDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.Figure 14-4. Alk

14−5brightness effect is even reversible when the finalproduct is exposed to sunlight.Mechanical pulping bleaching is done with sodiumhydrosulfite (Na

14−6this a very corrosive solution and potentiallyerosive due to the percentage of stock content.Design ConsiderationsD Highly corrosive chemical (not

14−7Oxygen (O) StageValveTag #ApplicationDescriptionControlFunctionVee-Ball HPBV V150E1 MC Control T S P2 Bleaching Agent Valve T P3 Pulp/Chemical Mix

14−8Figure 14-7. Oxygen (O) Stage

www.Fisher.comChapter 15Stock PreparationStock preparation is the start of the papermakingprocess and is the controlling factor over finalpaper qualit

15−2Figure 15-2. PulperDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.diluted to a slurry in order to break the fiber

15−3Figure 15-4. Disc RefinerDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.2. Jordan (or Conical) refiner: In this

15−4Figure 15-7. Thin Stock SystemDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.Figure 15-8. Fan PumpDrawing is from

15−5Figure 15-10. Fisher Vee-Ball and SKF Actuator Basis Weight ValveFigure 15-11. Disc SaveallDrawing is from TAPPI’s Making Pulp andPaper Series and

1−11Figure 1-21. Comprehensive Packing Material Arrangementsfor Globe-Style Valve BodiesB2565Figure 1-19. Mechanically Formed BellowsA5954Figure 1-20.

15−6Figure 15-13. Primary CleanersDrawing is from TAPPI’s Making Pulp and Paper Series and is used with permission.Figure 15-14. Secondary CleanersDra

15−7Figure 15-15. Deaeration ChamberDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.Figure 15-16. Compact Stock Prep S

15−8Figure 15-19. Centrifugal Deaeration ChamberFigure 15-17. Compact Stock Mixing TankDrawing is from TAPPI’sMaking Pulp and Paper Se-ries and is use

www.Fisher.comChapter 16Wet-End ChemistryIn this chapter, we will be discussing materials,other than fibers, that are added to the slurry offibers bef

16−2Figure 16-1. Stock Approach SystemDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.FillersFor most copy paper, arou

16−3Titanium Dioxide (TiO2) ApplicationsTitanium dioxide is used as a paper additive toincrease brightness and opacity. It is a fine whitepowder that

16−4

www.Fisher.comChapter 17Paper MachineWet EndThe paper machine is essentially a series ofprocesses all tied together (figure 17-1). Theseprocesses are

17−2Figure 17-2.Drawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.Figure 17-3. Multitube Tapered ManifoldDrawing is from

17−3Figure 17-5. Hydraulic HeadboxDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.turbulence inside the headbox and to

1−12Figure 1-22. Measurement Frequency for ValvesControlling Volatile Organic Chemicals (VOC)B2566Laminated and Filament GraphiteD Suitable for high t

17−4fabric producing a mat of fiber on the fabricsurface. The jet velocity at which the stock isdeposited onto the fabric is very important. Thisproce

17−5Figure 17-7. Stratified HeadboxDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.Figure 17-8. Cylinder FormerDrawing

17−6Figure 17-10. Top-Wire FormerDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.D Top-Wire or Hybrid Formers — This d

17−7Figure 17-11. Straight-Through PressDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.Figure 17-12. Roll PressDrawin

17−8Figure 17-15. Modern Straight-Through PressDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.Figure 17-14. Shoe Pres

17−9Figure 17-16. Two-Tier Drying SystemDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.DryingAfter pressing, the shee

17−10Figure 17-18. Steam Drum and SiphonDrawing is from TAPPI’s Making Pulp andPaper Series and is used with permission.Figure 17-19. Condensate Proce

17−11the type of hood arrangement, 7 - 20 pounds of airare utilized for each pound of water evaporated.To prevent drips, buildup and corrosion within

17−12spool and the primary arms return to their originalposition.WinderThe purpose of the winder is to cut and wind thefull-width, large diameter pape

www.Fisher.comChapter 18Boilers — Water/Steam CycleThe efficient production of steam and electricity isan important function in the overall process of

1−13D Proper alignment of the valve stem or shaftwithin the bonnet bore.D Applying a constant packing stress throughBelleville springs.D Minimizing th

18−2Boiler Feedwater SystemThe BFW system begins at the DA and ends atthe inlet to the economizer. The main componentsare the DA, the boiler feed pump

18−3trim can be designed to handle the cavitatingconditions at startup and then standard equalpercentage or linear characteristic for steady-statecond

18−4are used for furnace walls and have a very shortlance with a nozzle at the tip. The lance rotates asit moves into the furnace and cleans the depos

18−5Typical Specifications:D easy-e, EW, or HPD Whisper TrimD FIELDVUE digital valve controller with lowtravel cutoffOptional:D Inline diffuser (if ex

18−6cavitating application. The end user needs toensure that there is not a sparger or diffuserdownstream emitting back pressure on the valve.This wil

18−7E1385Figure 18-1. Water/Steam Cycle Diagram

18−8Figure 18-2. Power or Recovery Boiler Upper Convective SectionE1386

D103540X012 Printed in USA / 3M / 01-11 / ILEmerson Process ManagementMarshalltown, Iowa 50158 USASorocaba, 18087 BrazilChatham, Kent ME4 4QZ UKDu

1−14Figure 1-24. ENVIRO-SEAL PTFE Packing SystemA6163Figure 1-25. ENVIRO-SEAL Duplex (PTFE andGraphite) Packing SystemKALREZt Valve Stem Packing (KVSP

1−15Figure 1-27. ENVIRO-SEAL GraphitePacking System for Rotary ValvesW6125-1placement of PTFE minimizes control problems,reduces friction, promotes se

1−16Figure 1-28. Characterized Cages for Globe-Style Valve BodiesW0958 W0959 W0957QUICK OPENING LINEAR EQUAL PERCENTAGEFigure 1-29. Inherent Flow Char

1−17Figure 1-30. Typical Construction to ProvideQuick-Opening Flow CharacteristicA7100rate at the time of the change. The change in flowrate observed

1−18Conventional globe-style valve bodies can be fittedwith seat rings with smaller port size than normaland valve plugs sized to fit those smaller po

1−19Flow CharacteristicThe next selection criterion, “inherent flowcharacteristic”, refers to the pattern in which theflow at constant pressure drop c

1−20The threads usually specified are tapered femaleNPT on the valve body. They form ametal-to-metal seal by wedging over the matingmale threads on th

1−21After going through all the criteria for a givenapplication, the selection process may point toseveral types of valves. From there on, selectionbe

Copyright © 2011 Fisher Controls International LLC All Rights Reserved.Fisher, ENVIRO-SEAL, Whisper Trim, Cavitrol, WhisperFlo, Vee‐Ball, Control‐Di

1−22Table 1-3. Control Valve Characteristic RecommendationsLiquid Level SystemsControl Valve Pressure DropBest InherentCharacteristicConstant ΔP Linea

1−23Table 1-4. Control Valve Leakage StandardsANSIB16.104-1976Maximum Leakage Test Medium Pressure and TemperatureClass II 0.5% valve capacity at full

1−24

www.Fisher.comChapter 2Actuator SelectionThe actuator is the distinguishing element thatdifferentiates control valves from other types ofvalves. The f

2−2Actuator designs are available with a choice offailure mode between failing open, failing closed,or holding in the last position. Many actuatorsyst

2−3An actuator made specifically for a control valveeliminates the chance for a costly performancemismatch. An actuator manufactured by the valvevendo

2−4DIAPHRAGMDIAPHRAGM CASINGDIAPHRAGMPLATEACTUATOR SPRINGACTUATOR STEMSPRING SEATSPRING ADJUSTORSTEM CONNECTORYOKETRAVEL INDICATOR DISKINDICATOR SCALE

2−5Figure 2-3. The Fisher 2052 spring-and-diaphragm actuator has many features to provideprecise control. The splined actuator connectionfeatures a c

2−6actuator and operate it much like a spring-and-diaphragm. These designs use a single-actingpositioner that loads the piston chamber to movethe actu

2−7available within a given package size. Additionally,electric actuators are stiff, that is, resistant to valveforces. This makes them an excellent c

2−8Table 2-2. Recommended Seat Load Per Leak Class forControl ValvesClass I As required by customerspecification, no factory leak testrequiredClass II

2−9Table 2-3. Typical Packing Friction Values (Lb)Stem Size(Inches)ANSIClassPTFE PackingGraphiteRibbon/FilamentSingle Double5/16 All 20 30 – – –3/8 12

2−10Table 2-4. Typical Rotary Shaft Valve Torque Factors V-Notch Ball Valve with Composition SealFisher TCMt Plus Ball SealValve Size,NPSValve ShaftDi

2−11Actuator Selection SummaryD Actuator selection must be based upon abalance of process requirements, valverequirements and cost.D Simple designs su

2−12

www.Fisher.com*Some information in this introductory material has been extracted from ANSI/ISAS75.01 standard with the permission of the publisher, th

3−2Figure 3-1. Liquid Critical Pressure Ratio Factor for Waterequation. This is the mathematical statement ofconservation of the fluid mass. For stead

3−3applied and elevation changes have beenneglected (again using upstream conditions as areference):òV122gc) P1+òVVC22gc) PVC ( 6 )In the equation

3−4Figure 3-2. Liquid Critical Pressure Ratio Factor for Liquids Other Than WaterA2738-1In order to assure uniformity and accuracy, theprocedures for

* The ability to recognize which terms are appropriate for a specific sizingprocedure can only be acquired through experience with different valve siz

iiiTable of ContentsIntroduction vChapter 1 Control Valve Selection 1-1Chapter 2 Actuator Selection 2-1Chapter 3 Liquid Valve Sizing

3−6Table 3-1. Abbreviations and TerminologySymbol SymbolCvValve sizing coefficient P1Upstream absolute static pressured Nominal valve size P2Downstrea

3−7Table 3-2. Equation Constants(1)N w q p(2)gT d, DN10.08650.8651.00- - -- - -- - -m3/hm3/hgpmkPabarpsia- - -- - -- - -- - -- - -- - -- - -- - -- - -

3−8In the above equation, the “K” term is thealgebraic sum of the velocity head losscoefficients of all of the fittings that are attached tothe contro

3−9Figure 3-3. Liquid Critical Pressure Ratio Factor for WaterFor valves installed with fittings attached:DPmax(LP)+ǒFLPFPǓ2ǒP1* FFPVǓ(29)where,P1

3−10anticipated requirements. The line size is 8-inches,and an ANSI Class 300 globe valve with an equalpercentage cage has been specified. Standardcon

3−11where,SK + K1) K2+ 1.5ǒ1 *d2D2Ǔ2+ 1.5ǒ1 *1664Ǔ2+ 0.84andFp+ƪ1 )SKN2ǒCvd2Ǔ2ƫ*1ń2+ƪ1 )0.84890ǒ20342Ǔ2ƫ*1ń2+ 0.93andCv+qN1FpP1*P2GfǸ+800(1.0)(0.93)25

3−12Once the value of the pulp stock correction factoris known, determining the required flow coefficientor flow rate is equivalent to basic liquid si

3−13Figure 3-5. Pulp Stock Correction Factors for Mechanical PulpE1378Figure 3-6. Pulp Stock Correction Factors for Recycled PulpE1379

3−14

www.Fisher.comChapter 4Cavitation and FlashingSevere Liquid Flow SizingProper control valve sizing is important tosuccessful plant operation. However,

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4−2While the exact mechanisms of liquid choking arenot fully confirmed, there are parallels betweenthis and critical flow in gas applications. In gasf

4−3Figure 4-3. Typical Cavitation DamageW1350where:FL = KmǸFF = rcN1 = units factorCavitationClosely associated with the phenomenon ofchok

4−4Figure 4-5. Pressure Profiles for Flashing and Cavitating FlowsA3445If both of these conditions are met, the possibilityexists that cavitation will

4−5Figure 4-7. Viscous Flow Correction FactorsA3446losses were proportional to the square of thevelocity.In the laminar flow regime, these same losses

4−6Figure 4-8. The implosion of cavitation vapor cavities is rapid, asymmetric and very energetic. The mechanics of collapse give rise to high velocit

4−7dominant. Analytical estimations of vapor bubblecollapse pressures do not suggest that the shockwaves are on a damaging order of magnitude —at leas

4−8FF = the liquid critical pressure ratio factor. Can beobtained from the following equation:FF+ 0.96 * 0.28PvPcǸKc: Cavitation coefficient. A valve

4−9recent experience should be used to select thebest valve for specific applications.Hardware Choices for FlashingApplicationsIt was stated previousl

4−10Figure 4-10. Rotary plug valves, such as the V500 Vee-Ball valve(reverse flow trim direction, trim level 3) have excellenterosion resistance and p

4−11impingement on a material surface will not occuras there is essentially no material surface. Thissystem design will help prevent flashing damage.H

vPulp and Paper Control ValvesIntroductionThis sourcebook’s intent is to introduce a pulpand paper mill’s processes, as well as the use ofcontrol valv

4−12Figure 4-13. By combining the geometric effects ofthick plates and thin plates, it is possible to designa flow passage that optimizes capacity and

4−13Figure 4-14. Cavitrol IV trim provides cavitationprotection at pressures to 6500 psi. It uses expanding flow areas to affect a four-stagepressure

4−14backpressure provided may allow cavitation tooccur.D If the backpressure device becomes worn,the backpressure will decrease and cavitation inthe v

www.Fisher.comChapter 5Gas SizingThis chapter addresses the six-step procedure forsizing control valves for compressible flow usingthe standardized IS

5−2to produce critical, or maximum, flow through thevalve when Fk = 1.0When the control valve to be installed has fittings,such as reducers or elbows

5−3source is a header maintained at 500 psig and500_F. A 6-inch line from the steam main to theprocess is being planned. Also, make theassumption that

5−4Cv = 236, from step threeandKi+ K1) KB1+ 0.5ǒ1 *d2D2Ǔ2)ƪ1 *ǒdDǓ4ƫ+ 0.5ǒ1 *4262Ǔ2)ƪ1 *ǒ46Ǔ4ƫ+ 0.96where D = 6 inchesso:XTP+0.690.952ƪ1 )(0.69)(0.96)

5−5Table 5-1. Abbreviations and TerminologySymbol SymbolCvValve sizing coefficient P1Upstream absolute static pressured Nominal valve size P2Downstrea

5−6Table 5-2. Equation Constants(1)N w q p(2)gT d, DN10.08650.8651.00- - -- - -- - -m3/hm3/hgpmkPabarpsia- - -- - -- - -- - -- - -- - -- - -- - -- - -

5−7Table 5-3. Flow Coefficient TableGas or Liquid FlowModified EqualPercentage CharacteristicValveSize,InchesMinimumThrottlingCV(1)CoefficientsValve R

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5−8Table 5-4. Representative Sizing Coefficients for ED Single-Ported Globe Style Valve BodiesValve Size(inches)Valve Plug Style Flow CharacteristicPo

www.Fisher.comChapter 6Control Valve NoiseNoise has always been present in control valves.It is a natural side effect of the turbulence andenergy abso

6−2hertz, and the A-weighting factor is essentiallyzero in this range. Thus, there is negligibledifference between the dB and dBA ratings.Sound Charac

6−3Table 6-2. Combined Noise CorrectionsdBA1 - dBA2dBA Adder to Loudest Noise Source0 3.011 2.542 2.123 1.764 1.465 1.26 <1To use table 6-2:1. Dete

6−4levels can be produced in a two-inch line with aslittle as a 200 psi pressure drop. Major sources ofaerodynamic noise are the stresses or shearforc

6−5times when this is the area of interest, but thenoise levels on the outside of that pipe are theprime requirement. This method must account forthe

6−6Figure 6-2. Valve with Whisper Trim I and Inline Diffuser CombinationW2618When the pressure drop ratio exceeds 0.65, theWhisper Trim I cage loses i

6−7Figure 6-4. WhisperFlo TechnologyW7065W7056Fisher WhisperFlot trim (figure 6-4) is well-suitedfor applications that have high noise levels andrequi

6−8Figure 6-6. Valve and Vent Diffuser CombinationW2672D Acoustical or thermal insulationThe noise level near the valve can be lowered byapplying insu

6−9Figure 6-7. Cavitrol III TrimW2479Figure 6-8. NotchFlo DST Trim forFisher Globe Style ValvesW8538However, if cavitation damage can be eliminatedusi

www.Fisher.comChapter 1Control Valve SelectionIn the past, a customer simply requested a controlvalve and the manufacturer offered the productbest-sui

6−10Control Valve Noise SummaryThe requirement for noise control is a function oflegislation to protect our wellbeing and to preventphysical damage to

www.Fisher.comChapter 7Steam ConditioningIntroductionPower producers have an ever-increasing need toimprove efficiency, flexibility, and responsivenes

7−2Figure 7-1. Temperature enthalpy diagram forwater. Note that the greatest amount of thermalenergy input is used to vaporize the water.Maximum effic

7−3production of condensate liberates the enthalpy ofevaporation, the major component of the totalthermal energy content. The temperature-enthalpy di

7−4After the valve, the steam will have the followingconditions:Conditions: P2 = 45 psia Enthalpy = 1198.9 BTU/LBReferencing a set of stea

7−5Figure 7-4. The DMA/AF desuperheater utilizes variable-geometry, back-pressureactivated spray nozzles.W6310-1dependent on the pressure differentia

7−6Figure 7-6. The DSA desuperheater useshigh-pressure steam for rapid and completeatomization of spraywater in low-velocity steamlines.W6311-2Install

7−7Figure 7-7. The DSA desuperheater utilizes two external control valves: a spraywater unit and an atomizing steam valve.DSA DESUPERHEATERC0817 / ILF

7−8Figure 7-9. The TBX utilizes an externalspraywater manifold with multiple nozzles formoderate to large volume applications.W8493-1Steam conditionin

7−9Figure 7-11. The TBX showing externalspraywater manifold.W8520provides Class V shutoff and a linear flowcharacteristic.The TBX typically uses high-