Transcription

Mark One Control Valves

Valtek Mark One Control ValvesBody AssemblyFail-safe springOHeavy GuidingTwo widely spacedguides on large-diameterstem. Plug does notguide in retainerHigh ThrustCylinder ActuatorThree standard sizes covermost applications. Each iseasily reversible andfeatures exceptionalstiffness, repeatability andlow hysteresisSHigh PerformancePositioning accuracyto 0.002 inch (0.05 mm)Clamped-in Seat RingValve may be disassembledquickly and easily byremoving bonnet boltsVersatilityANSI Class 600 (PN 100)body used for ANSI Class150, 300 and 600 (PN 16,40, 100) ratings through4-inch (DN 100)Figure 1: Mark One Body AssemblyThe Valtek Mark OneTM globe control valve offers superiorperformance in liquid and gaseous services, while alsopermitting easy, fast and inexpensive maintenance.The spring-cylinder actuated Mark One valve providesstiffness and maintains high positioning accuracy, repeatability, controlled high speed, and faithful response.The Mark One valve handles up to 150 psig (10.3 barg)supply air and has the thrust to shut off against muchhigher fluid pressures.The Mark One valve is designed so the spring, supplyair pressure and fluid pressure itself combine to produce exceptionally tight shutoff. A self-aligning seat ringfurther enhances the shutoff capability of the Mark Onevalve.2The Mark One valve is typically double top-stem guidedand completely avoids contact between the plug andseat retainer. Many globe valve maintenance problemscan be traced to cage-guiding. The close metal-tometal contact between the cage and plug often result ingalling and sticking.The clamped-in seat and top-entry trim permits easy,quick maintenance. Plus, with the Mark One valve’shigh degree of parts interchangeability, fewer inventoryparts are required. In addition, the actuator is lighter,smaller and easier to handle than comparable diaphragm actuators.The Valtek Mark One control valve is the industry choicefor a simple, reliable, tough globe valve.Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611

Valtek Mark One Control ValvesAdvantages and FeaturesAdvantagesFeaturesDesign provides lowertotal lifetime costHigh interchangeability between sizes and other Valtek control productsValve design minimizes requirements for stocking spare partsRugged, heavy-duty parts provide extended lifeActuator design allows simple, easy maintenanceVersatileGlobe, angle, three-way, and jacket styles offer multiple face-to-facestandardsTrim that does not stick or gallDouble-stem guiding located out of flow streamGenerous clearance between plughead and seat retainerEliminates galling associated with cage-guidingEasy, fast and inexpensiveTop-entry servicingClamped-in seat ringEvenly compressed gasket – controlled gasket compressionSeparable flangesHigh degree of parts interchangeabilitySmall, lightweight designLeakproof when closedSelf-aligning seat ringAssisted shutoff from fluid pressure, cylinder spring, cylinder pressureHigh-thrust, spring-cylinder actuatorSpring fails valve to desired position, pneumatics provide additional forceBuilt for toughest serviceCorrosion-resistant constructionHigh thrust overcomes high pressuresAnti-cavitation and noise-trim optionsHeavy-duty plug stemFactory Mutual approved as a fuel service valve (0.75 - 3-inch/DN 20 - 80)Compact and easy to installCylinder actuator smaller than most competitor’s actuatorsLower center of gravity than comparable actuatorsLighter weight means less pipe stress from static and dynamic loadsSeparable end flanges allow the valve to be installed in manyorientations and compensate for flange misalignmentReliable, predictable serviceStiff, high-thrust cylinder actuatorAccurate positioningHigh repeatabilityFaithful responseControlled, high-speed stroking actionFlowserve Corporation, Valtek Control Products, Tel. USA 801 489 86113

Valtek Mark One Control ValvesComponentsAdjusting Screw GasketAdjusting ScrewSpring ButtonSpringPiston Retaining NutPiston Stem O-ringActuator Stem SpacerCylinderActuator Stem BushingPistonActuator Stem O-ringPiston O-ringActuator StemYoke O-ringCylinder Retaining RingStem ClampOStroke PlateGland FlangeStem BellowsUpper PackingSYokeYoke ClampUpper Stem GuidePacking SpacerUpper Stem Guide LinerBonnetBonnet FlangeBoltingBonnet FlangeSeat RetainerLower PackingSeat RingBonnet GasketSeat Ring GasketLower Stem GuideBodyLower StemGuide LinerHalf RingPlugEnd FlangeFigure 2: Mark One Control Valve4Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611

Valtek Mark One Control ValvesBody StylesFigure 3: Globe-style BodyFigure 4: Three-way BodyGlobe-style bodies feature smooth, streamlined,constant-area internal passages with no pockets,permitting high capacity with minimum turbulence. Theyare designed with nearly constant wall thickness,providing lower weight and cost when manufactured inexpensive stainless or alloy steels.Three-way bodies are used for either combining ordiverting services. Due to Flowserve’s excellent partsinterchangeability, a standard globe valve easily converts to three-way service with the addition of a threeway adaptor, upper seat ring, two gaskets, three-wayplug and longer bonnet flange studs.Figure 5: Angle-style BodyFigure 6: Steam-jacketed BodyExcept for the body and 1.5-inch (DN 40) seat ring, theangle-style Mark One valve is completely interchangeable with the globe style – all other valve parts remainthe same. For additional body protection, a venturi seatring, extending to the outlet flange, is available.The steam-jacketed Mark One valve uses a standardglobe style body with oversized, blind flanges for a fulljacket or standard flanges for a partial jacket. The jacketis rated for 150 psig (10.3 barg) and is equipped with a0.75-inch NPT supply and drain connection.Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 86115

Valtek Mark One Control ValvesEnd Connections, Flanges and BoltingMark One body facings come standard as raised face for eitherseparable and integral flanges. To achieve better sealing withmating piping, the flange face is machined with spiral groovedserration. Other optional facings include smooth face, flat face,ring-joint, large and small tongue, and large and small groove.Separable End FlangesInterchangeable separable flanges are standard for valvebodies 0.5- through 4-inch (DN 15 -100) in ANSI Class 150, 300and 600 (PN 16, 40, 100). With separable end flanges, an ANSIClass 600 (PN 100) body can be adapted for ANSI Class 150,300 or 600 (PN 16, 40, 100) service by simply changing the e flanges are usually furnished in carbon steel formaximum cost savings, although stainless steel can be specified if needed.Bonnet FlangeThe bonnet flange incorporates the same separable design asthe end flanges and is normally manufactured in carbon steel;however, it can be specified in stainless steel when required.Bonnet Flange BoltingEnd FlangeANSI Class 150(PN 16)BodyANSI Class 600(PN 100)Figure 7:Separable End and Bonnet FlangesAll sizes use studs and nuts that are furnished in 304 and 316stainless steel, suitable for -423 to 1500 F (-253 to 816 C).These temperature limits are for maximum pressure permittedby ANSI B16.34, latest edition.Table 1: End nge –Steel chesDN0.5-415-100ANSIPN150- 600 16-1000.5-48 15-1200150160.5-48 15-1200300-60040-1000.5-24 15-600900-2500 160-4000.5-215-50150-6000.5-215-50900-2500 160-4000.5-415-50150-6000.5-415-50900-2500 6-1000.5-24 15-6006RatingClassANSI / 00S75.12ANSI Class 300(PN 40)ANSI Class 600(PN 100)Figure 8: End FlangesS75.15900-2500 160-400Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611

Valtek Mark One Control ValvesGaskets and ClampsThe Mark One valve is designed with the bonnet andseat ring gaskets fully retained. Since the bonnetbottoms metal-to-metal in the body, the bonnet gasketcompression is determined by the depth of the gasketstep on the bonnet, which is machined to provide therequired gasket compression.When the bonnet is fully installed, force is transmittedthrough the seat retainer to secure the seat ring inposition. The body, seat retainer and seat ring are allmachined to close tolerances to provide the propergasket compression. Unlike the bonnet, the seat ringdoes not always bottom in the body, allowing thissmall clearance to compensate for manufacturingtolerances and thermal expansion.Bonnet GasketSeat RingGasketFigure 9: Body GasketsTable 2: Gasket SpecificationsMaximumGasket Temp. F C350177MinimumGasket Temp. F C-200-130TypeGasket MaterialStandardFlatPTFEGasketsSpiral Wound304 S.S./AFG750400-20-30Spiral Wound316 tsFlatGraphite**1500**816**-320-196Spiral Wound316 S.S./Graphite**1500**816**-320-196Hollow O-ringInconel X-7501500816-20*-30**Lower temperature available upon request.**Limited to 800 F (427 C) for oxidizing service.Yoke ClampsThe actuator is typically attached to the Mark One bodyassembly with two precision-cast, stainless steel yokeclamps. In some cases, however, the actuator is bolteddirectly to the bonnet. Each clamp has an inclined planesurface which, when bolted together, securely fastensthe actuator yoke to the bonnet. Unlike conventionalthreaded clamps, the clamp design permits easy removaleven under extremely corrosive conditions.Associated bolts and locknuts are supplied in platedcarbon steel, although stainless steel is also availablewhen required.Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611YokeClampFigure 10: Yoke Clamp7

Valtek Mark One Control ValvesBonnet TypesStandard BonnetExtended BonnetCold BoxExtended BonnetFigure 11: Mark One Bonnet TypesStandard BonnetGuardian II Formed Metal Bellows Seal BonnetThe Mark One bonnet is usually constructed of thesame material as the body and handles temperatures from -20 to 750 F (-30 to 400 C). SeeTable 4 on page 9 for packing limitations.The Guardian II formed metal bellows seal can be usedwhenever service fluid leakage to atmosphere needs to bereduced to an absolute minimum. The standard metalbellows seal is rated for operation in processes ranging intemperature from -320 F to 1100 F (-196 to 593 C) andpressures to 1100 psig (75.9 barg).The flexible metal bellows is typically constructed of Inconel625 and is also available in Hastelloy C-22.The Guardian II bellows seal allows for outside pressure tominimize bellows squirm, prolonging bellows life.Extended BonnetThe extended bonnet protects the packing fromexcessive heat or cold, which may inhibit valveperformance. The bonnet is constructed of carbon steel for temperatures from -20 to 800 F(-30 to 427 C) and of 304 or 316 stainless steelfor -150 to 1500 F (-100 to 816 C).Cold Box Extended BonnetThe cold box extended bonnet permits stagnated,moderate temperature gas to form in the bonnet,which protects the packing from the service fluid.Typically manufactured from 304 or 316 stainlesssteel, it handles temperatures down to -423 F(-253 C). Standard construction consists of stainless steel bonnet flange and bolting.8Guardian Metal Bellows Seal BonnetThe Guardian metal bellows seal provides protection againstunwanted packing leakage to atmosphere in processesinvolving caustic liquids or gases.The compact, lightweight design of the Guardian bellowsassembly makes it ideal for services less than 650 F(343 C) and 310 psig (21.4 barg). The precision-formedbellows is available in Inconel or Hastelloy C materials.NOTE: Bellows seals are designed for special service conditions and not to valve’s design class; therefore, complete andaccurate service conditions must be specified.Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611

Valtek Mark One Control ValvesPacking and GuidingPacking BoxStandard Valtek packing boxes are deeper than mostconventional types, providing the following advantages:3. Two widely spaced stem guides, when used with theMark One’s large plug stem diameter, provide exceptional guiding. The upper stem guide also actsas a packing follower; the lower guide is situatedclose to the plug head for additional guiding support,ensuring accurate alignment of plug and seat ring.1. The spacing between the wiper set and the mainupper packing set prevents contamination of theupper packing. The upper set is positioned far enoughaway from the wiper set to avoid contact with anypart of the plug stem that has been exposed to theflowing medium. The wiper set is designed to minimize the amount of fluid on the plug stem.4. Graphite-lined stainless steel guides provide superior guiding over wide temperature ranges and completely eliminate guide/stem galling. A variety ofguides are available for various applications, including solid brass, Alloy 6 and glass-filled PTFE-linedstainless steel.2. Bonnets are designed to permit a wide variety ofpacking configurations, including a double set ofpacking, without changing bonnets.Table 3: .Min.Temp.UpperGuideMaximumPressureGlass-filled150 psig / 10.3 barg @100 F / 38 CPTFE-lined S.S. 350 F -423 F177 C -253 C100 psig / 6.9 barg @ 350 F / 177 CSolid Bronze500 F -423 F260 C -253 CSame as bodySolid Alloy 61500 F -423 F816 C -253 CSame as bodyTable 4: PackingBonnetTypeStandard**BonnetPacking MaterialService FluidTemperatureLimitationPTFE, PTFE/AFP andGlass-filled PTFEGraphite/AFPGraphite/AFP, Inconel wire500 F500 F750 F750 F*260 C260 C400 C400 C*Graphite***PTFE, PTFE/AFP andGlass-filled PTFEGraphite/AFPGraphite/AFP, Inconel wire750 F*600 F400 C*316 C1200 F1200 F650 C650 CGraphite***Cryogenic Extended Length**1500 F816 C15, 18-inch (38, 46 cm)24, 27-inch (38, 46 cm)-320 F-423 F-196 C-253 CExtended**BonnetUpperPackingSet1500 F -320 F 1400 psig / 96.6 barg up to 2-in / DN 50816 C -196 C 1000 psig / 69.0 barg 3-4-in / DN 80-100850 psig / 58.6 barg 6-in DN 150 & upPTFEPTFEFlowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611LowerGuideWiperPackingSetFigure 12: Typical PTFEV-ring Arrangement* Temperatures assume environmental temperature isless than 90 F (32 C); 8–12-inch (DN 200-300)ANSI Class 150-600 (PN 160-400) and 3–12-inch(DN 80-300) ANSI Class 900-2500 (PN 160-400)handles temperatures to 850 F (454 C).** ANSI B16.34 specifies acceptable pressure temperature limits for pressure retaining materials. Consultthe factory for additional information.*** Do not use graphite above 800 F (427 C) inoxidizing service such as air or oxygen. The use ofgraphite packing may require oversize actuators orheavier springs due to added friction.9

Valtek Mark One Control ValvesFlow Characteristics, Trim Types050% Valve Linear100% FlowQuick-open50% Valve n plugs are used for on-off service andare primarily designed to produce maximum flowquickly.100INSTA50TYPICAL% FlowLinearLinear inherent characteristic produces equalchanges in flow per unit of valve stroke regardlessof plug position. Linear plugs are used on thosesystems where the valve pressure drop is a majorportion of the total system pressure qualPercentageCTIISREST% FlowEqual percentage is the characteristic mostcommonly used in process control. The change inflow per unit of valve stroke is directly proportionalto the flow occurring just before the change ismade. While the flow characteristic of the valvemay be equal percentage, most control loopsproduce an installed characteristic, which approaches linear when the overall system pressuredrop is large relative to that across the valve.T100Equal Percentage50050% Valve Stroke100Figure 13: Flow CharacteristicsTrim TypesThree trim types are available. Standard full-areatrim provides maximum CV. Reduced trim is available in a wide variety of sizes when lower CVvalues and large bodies are required. Integral trimuses a special seat machined into the body and anoversized plug to provide additional CV beyond thecapabilities of full-area trim.Mark One valves can be converted from one trimtype to another since all seat rings and plugs witha given size and pressure class are completelyinterchangeable. Integral trim is available byremoving the seat ring and by changing the plug.10Full AreaReducedIntergralFigure 14: Typical Trim TypesFlowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611

Valtek Mark One Control ValvesStandard Trim, Pressure-balanced lug SealsPlug VentPlugPlugSeatRingPressurebalancedSleeveFigure 15: Standard TrimFigure 16: Pressure-balanced TrimMark One valve trim is designed to avoid the difficultiesassociated with screwed-in seats and cage-guiding.The seat ring is clamped into the body by the bonnetand seat retainer; thus, removal of the seat is easy evenunder extremely corrosive conditions.Unlike cage-guided trims that easily gall and stick, MarkOne plugs are double-stem guided, avoiding contactbetween the seat retainer and plug. Because no contact is made with the plug, the retainer can be constructed of stainless steel rather than costly hard materials. The flow characteristic is determined by the plugcontour, rather than by the opening in the retainer.Low-noise seat designs have been developed for betternoise control in standard Mark One valves.In high pressure drop applications, pressure-balancedtrim is used to reduce the thrust necessary to stroke theplug by reducing the trim off-balance area. Because thepressure-balanced plug fits closely to the retainer, thistrim should only be used in generally clean services.Metal SeatsMetal seated valves handle Class IV shutoff (ANSIB16.104, 1976 – FCI 70-2). This class calls for maximum permissible seat leakage of 0.01 percent of ratedvalve capacity. All Valtek control valves are seat-leaktested after assembly and are substantially lower inleakage than called for by this class. This exceptionalseat tightness is obtained by aligning the seat ring withthe plug during assembly. Additional seat tightnessusing metal seats is available as an option.Flow direction is under-the-plug for fail-closed andover- the-plug for fail-open. The seal area less the stemarea is designed to be slightly larger than the seat area;therefore, the plug is off-balanced to close for flowunder the seat and off-balanced to open for flow overthe seat.Soft SeatsThe Mark One soft seat is used in applications requiringANSI Class VI 'bubble-tight' shutoff. Its design consistsof an elastomer sandwiched between two metal pieces.The assembled soft seat is interchangeable with thehard seat for a given size and pressure rating. Insertsare often constructed of PTFE; therefore, maximumtemperature should be below 300 F (150 C) at290 psig (20 barg). For temperatures below -85 F(-65 C), PTFE soft seats can be used in high-pressureapplications.Table 5: Standard Seal Temperature RangesPTFE SleeveRene 41Insert Retainer-320 F (-196 C) @ full ratingor 300 F (150 C)@ 150 psig (10.3 barg)800 to 1600 F427 to 871 CSpring-energized TFE -365 to 575 F-221 to 302 CViton-40 to 225 C-40 to 437 FFlowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611Soft Seat RingInsertFigure 17: Typical Soft Seat Configuration11

Valtek Mark One Control ValvesTrim Materials, DataTable 6: Material Hardness RatingsStandard plug and seat ring material is 316 stainlesssteel, except special alloy bodies where trims are furnished in the same material as the body. A wide varietyof services are successfully handled by stainless steeltrim parts. Nevertheless, a general rule is to considerhard trim for all choked flow