Valtek Mark OneValtek Mark OneControl Valves1
Valtek Mark OneBody AssemblyModular Piston Actuator:Three standard sizes covermost valves. Each is easilyreversible. Stiffness,repeatability, low hysteresis.Fail-Safe SpringOHeavy Guiding:Two widely spacedguides on large-diameterstem. Plug does notguide in retainer.Interchangeability:Class 600 body used forClass 150, 300 and 600ratings through 4-inch.SPerformance:Positioning accuracyto .002 inch. Extremelyhigh thrust.Clamped-In Seat Ring:Valve may be disassembledquickly and easily byremoving bonnet bolts.Figure 1: Mark One Body Assembly – Class 150, 300 and 600The Valtek Mark OneTM globe control valve offers superiorperformance in liquid and gaseous services, while alsopermitting easy, fast and inexpensive maintenance.Unlike diaphragm-operated control valves, the springcylinder actuated Mark One provides stiffness andmaintains high positioning accuracy, repeatability, controlled high speed and faithful response. The Mark Onehandles up to 150 psig / 10.3 Barg supply air and has thethrust to shut off against much higher fluid pressures.Most diaphragm actuators rely entirely on springs toclose the valve, but the Valtek Mark One is designed sothe spring, supply air pressure and fluid pressure itselfcombine to produce exceptionally tight shutoff. A selfaligning seat ring further enhances the shutoff capability of the Mark One.2Many globe valve maintenance problems can be tracedto cage-guiding. The close metal-to-metal contact between the cage and plug often result in galling andsticking. The Mark One, however, is double top-stemguided and completely avoids contact between the plugand seat retainer.The clamped-in seat and top-entry trim permits easy,quick maintenance. Plus, with Mark One’s high degreeof parts interchangeability, fewer inventory parts arerequired. In addition, the actuator is lighter, smaller andeasier to handle than comparable diaphragm actuators.The Valtek Mark One is the industry choice for a simple,reliable, tough globe valve.
Valtek Mark OneAdvantages and FeaturesAdvantagesFeaturesReliable, predictable serviceStiff, high-thrust cylinder actuatorAccurate positioningHigh repeatabilityFaithful responseControlled, high-speed stroking actionWon’t stick and shut downCage guiding eliminatedDouble stem guiding located out of flow streamGenerous clearance between plug head and seat retainerEasy, fast and inexpensiveTop-entry servicingClamped-in seat ringEvenly compressed gasket – controlled gasket compressionSeparable flangesHigh degree of parts interchangeabilitySmall, lightweight designLeakproof when closedHigh-thrust, spring-cylinder actuatorSelf-aligning seat ringAssisted shutoff from fluid pressure, cylinder spring, cylinder pressureSpring 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 (3/4 - 3-inch)Compact and easy to installCylinder actuator is smaller than comparable diaphragm actuatorsLower center of gravity than comparable diaphragm actuatorsLight weight means less pipe stress from static and dynamic loadsSeparable end flanges allow the valve to be installed in manyorientations and compensate for flange misalignmentDesign 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 maintenance3
Valtek Mark OneComponentsAdjusting 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 Valve4
Valtek Mark OneBody 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 Body1Except for the body and 1 /2-inch seat ring, the anglestyle Mark One is completely interchangeable with theglobe style – all other valve parts remain the same. Foradditional body protection, a venturi seat ring, extending to the outlet flange, is available.The steam-jacketed Mark One uses a standard globestyle body with oversized, blind flanges for a full jacketor standard flanges for a partial jacket. The jacket israted for 150 psig / 10.3 Barg and is equipped with a3/4-inch NPT supply and drain connection.5
Valtek Mark OneEnd 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 valve bodies 1/2- through 4-inch in class 150, 300 and 600 ANSI ratings,and for 6- and 8-inch bodies in Class 300 and 600. Withseparable end flanges, a class 600 body can be adapted forClass 150, 300 or 600 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 BoltingClass 150End FlangeClass 600BodyFigure 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, 1988.Table 1: End ConnectionsEnd ConnectionSeparable tionalFaceto-Face/2 - 4150 - 600ANSI (a)ISA6-8300 - 600ISA (b)Integral Flange –1/2 - 48150ISASteel & Alloys1300 - 600ISA/2 - 481/2 - 24ScrewedSocketweldButtweld900 - 2500ISA (c)1/2 - 2150 - 600ANSI1/2 - 2900 - 2500ISA (c)1/2 - 2150 - 600ANSI1/2 - 2900 - 2500ISA (c)1/2 - 4150 - 600ANSI6 - 36150 - 600ISA900 - 2500ISA (c)1/2 - 246ISAClass 300Class 600Figure 8: End FlangesISA(a) ANSI B16.10 Class 600 globe valves(b) ANSI/ISA S75.03, 1985(c) See Table 20
Valtek Mark OneGaskets and ClampsThe Mark One is designed with the bonnet and seat ringgaskets fully retained. Since the bonnet bottoms metalto-metal in the body, the bonnet gasket compression isdetermined by the depth of the gasket step on thebonnet, which is machined to provide the requiredgasket 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 bottom in the body, allowing this smallclearance to compensate for manufacturing tolerances and thermal expansion.Bonnet GasketSeat RingGasketFigure 9: Body GasketsTable 2: Gasket SpecificationsTypeGasket MaterialMaximumGasketTemp. F / CMinimumGasketTemp. F / CStandardFlatTeflon (TFE)350 / 177-200 / -130GasketsSpiral Wound304 S.S./AFG750 / 400-20 / -30Spiral Wound316 S.S./AFG1000 / 538-20 / -30FlatAFG600 / 318-20 / -30FlatKEL-F350 / 177-320* / -196*AlternateFlatTeflon (FEP)400 / 204-320 / -196GasketsFlatGrafoil**1500** / 816**-320 / -196Spiral Wound316 S.S./Grafoil**1500** / 816**-320 / -196Hollow O-ringInconel X-7501500 / 816-20* / -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 Flowserve clamp design permitseasy removal even under extremely corrosive conditions.Associated bolts and locknuts are supplied in platedcarbon steel, although stainless steel is also availablewhen required.YokeClampFigure 10: Yoke Clamp7
Valtek Mark OneBonnet TypesStandard BonnetExtended BonnetCold BoxExtended BonnetFigure 11: Mark One Bonnet TypesStandard BonnetThe Mark One bonnet is usually constructed of thesame material as the body and handles temperaturesfrom -20 to 750 F / -30 to 400 C (See table 4 on page9 for packing limitations.)Extended BonnetThe extended bonnet protects the packing fromexcessive heat or cold, which may inhibit valve performance. The bonnet is constructed of carbon steelfor temperatures from -20 to 800 F / -30 to 427 Cand of 304 or 316 stainless steel for -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, whichprotecting the packing from the service fluid. Typicallymanufactured from 304 or 316 stainless steel, it handlestemperatures down to -423 F / -253 C. Standardconstruction consists of stainless steel bonnet flangeand bolting.8Guardian II Formed Metal Bellows SealBonnetThe Guardian II formed metal bellows seal can be usedwhenever service fluid leakage to atmosphere needs tobe reduced to an absolute minimum. The standardmetal bellows seal is rated for operation in processesranging in temperature from -320 F to 1100 F / -196 to 593 C and pressures to 1100 psig / 75.9 Barg.The flexible metal bellows is typically constructed ofInconel 625 and is also available in Hastelloy C-22.The Guardian II bellows seal allows for outside pressureto minimize bellows squirm, prolonging bellows life.Guardian Metal Bellows Seal BonnetThe Guardian metal bellows seal provides protectionagainst unwanted packing leakage to atmosphere inprocesses involving caustic liquids or gases.The compact, lightweight design of the Guardian makesit ideal for services less than 650 F / 343 C and 310psig / 21.4 Barg. The precision-formed bellows is available in Inconel or Hastelloy C materials.Bellows seals are designed for special service conditions and not to valve’s design class; therefore, completeand accurate service conditions must be specified.
Valtek Mark OnePacking and GuidingPacking BoxThe standard Valtek packing boxes are deeper than mostconventional types, providing the following advantages:1. The spacing between the wiper set and the main,upper 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.2. Bonnets are designed to permit a wide variety ofpacking configurations, including a double set ofpacking, without changing bonnets.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.4. Grafoil-lined stainless steel guides provide superiorguiding over wide temperature ranges and completely eliminate guide/stem galling. A variety ofguides are available for various applications, including solid brass, Stellite and glass-filled Teflon-linedstainless steel.Table 3: GuidesStandardMaterialsGrafoil ure1500 F /816 C-320 F /-196 C1400 psig / 96.6 Barg thru 2-inch1000 psig / 69.0 Barg 3 thru 4-inch850 psig / 58.6 Barg 6-inch & upGlass-filled150 psig / 10.3 Barg @100 F / 38 CTeflon-lined S.S.350 F177 C-423 F-253 C100 psig / 6.9 Barg @ 350 F / 177 CSolid Bronze500 F /260 C-423 F /-253 CSame as bodySolid Stellite1500 F /816 C-423 F /-253 CSame as bodyTable 4: PackingBonnetTypeUpperPackingSetService FluidTemperatureLimitation F / CStandard**Teflon, Teflon/AFP and500 / 260BonnetGlass-filled Teflon500 / 260Graphite/AFP750 / 400Graphite/AFP, Inconel wire750* / 400*Grafoil***750* / 400*Extended**Teflon,Teflon/AFP and600 / 316BonnetGlass-filled TeflonGraphite/AFP1200 / 650Graphite/AFP, Inconel wire1200 / 650Grafoil***1500 / 816Cryogenic Extended Length**15-, 18-inchTeflon-320 / -19624-, 27-inchTeflon-423 / -253LowerGuideWiperPackingSetPacking MaterialFigure 12: Typical TeflonV-ring Arrangement* Temperatures assume environmental temperatureis less than 90 F / 32 C; 8 through 12-inch Class150 through 600 and 3 through 12-inch Class900-2500 handles temperatures to 850 F / 454 C.** ANSI B16.34 specifies acceptable pressuretemperature limits for pressure retaining materials.Consult the factory for additional information.*** Do not use Grafoil above 800 F / 427 C inoxidizing service such as air or oxygen. The use ofGrafoil packing may require oversize actuators orheavier springs due to added friction.9
Valtek Mark OneFlow Characteristics, Trim Types5050% Valve 100% Flow50% Valve Stroke50050% Valve StrokeFigure 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.10Full Area100ISTICCTERHARACTNEINHERQuick OpenMark 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.100INSTA50TYPICAL% FlowLinearQuick open plugs are used for on-off service andare primarily designed to produce maximum INHE0Linear 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 drop.CTIISREST% 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 PercentageReducedIntergralFigure 14: Typical Trim Types100
Valtek Mark OneStandard Trim, Pressure-balanced lug SealsPlug VentPlugPlugSeatRingPressurebalancedSleeveFigure 15: Standard TrimFigure 16: Pressure-balanced TrimMark One trim is designed to avoid the difficultiesassociated with screwed-in seats and cage-guiding.The seat ring is clamped into the body by the bonnet andseat 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 contactis made with the plug, the retainer can be constructed ofstainless steel rather than costly hard materials. Theflow characteristic is determined by the plug contour,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. Becausethe pressure-balanced plug fits closely to the retainer,this trim should only be used in generally cleanservices.Metal SeatsThe Mark One soft seat is used in applications requiringANSI Class VI “bubble-tight” shutoff. Its design consists of an elastomer sandwiched between two metalpieces. The assembled soft seat is interchangeablewith the hard seat for a given size and pressure rating.Inserts are often constructed of Teflon, therefore, maximum temperature should be below 300 F / 150 C at290 psig / 20 Barg. For temperatures below -85 F /-65 C, Teflon soft seats can be used in high-pressureapplications.Metal 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 and overthe plug for fail-open. The seal area less the stem areais 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 SeatsTable 5: Standard Seal Temperature RangesTeflon SleeveNiResist Piston RingsBuna-N O-ring-60 to 250 F / -51 to 121 CRene 41800 to 1600 F / 427 to 871 CSpring energized TFE-365 to 575 F / -221 to 302 CVitonInsert Retainer-320 F / -196 C @ full ratingor 300 F / 150 [email protected] 150 psig / 10.3 Barg-20 to 800 F / -30 to 427 C-40 to 437 F / -40 to 225 CSoft Seat RingInsertFigure 17: Typical Soft Seat Configuration11
Valtek Mark OneTrim 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 conditions or for temperatures above 600 F / 316 C. Stellite No. 6 is stocked formany valve trim parts. This material offers a goodcombination of relative hardness and corrosion resistance. Special alloys, such as Alloy 20, Hastelloy C andMonel, are also available.TrimMaterialHardnessRockwell CCorrosion*Resistance316 S.S.8ExcellentStellite No. 644Good to Excellent416 S.S.40Fair440C S.S.56Fair17-4 PH40ExcellentColmonoy45-50Fair to GoodTungstenCarbide72Good on BasesPoor on Acids* General rule only. Check specific application.Table 7: Standard Unbalanced Valve/Actuator DataValve 10101012121214143RatingClassFull AreaTrim SizeSeat Area(sq. 50300-600.50.72.81.81.721.251.