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TECHNICAL BULLETINValtek Control ValvesMark One Control ValvesFCD VLENTB0001-02-AQ 08/14 (Replaces FCD-VLATB001)Experience In Motion

Valtek Mark One Control ValvesFCD VLENTB0001-02-AQ – 8/14Body AssemblyHigh Thrust CylinderActuator: Three standardsizes cover most applications.Each is easily reversible andfeatures exceptional stiffness, repeatability and lowhysteresis.Fail-safe springHeavy Guiding: Two widelyspaced guides on largediameter stem. Plug doesnot guide in retainer.Versatility: ANSI Class 600(PN 100) body used for ANSIClass 150, 300 and 600 (PN16, 40, 100) ratings through4-inch (DN 100)TMThe Valtek Mark One globe control valve offers superiorperformance in liquid and gaseous services, while also permittingeasy, fast and inexpensive maintenance.The spring-cylinder actuated Mark One valve provides stiffnessand maintains high positioning accuracy, repeatability, controlledhigh speed, and faithful response. The Mark One valve handlesup to 150 psig (10.3 barg) supply air and has the thrust to shut offagainst much higher fluid pressures.The Mark One valve is designed so the spring, supply air pres sureand fluid pressure itself combine to produce exceptionally tightshutoff. A self-aligning seat ring further enhances the shutoffcapability of the Mark One valve.2OSHigh Performance:Positioning accuracy to0.1% full scaleClamped-in Seat Ring:Valve may be disassembledquickly and easily by removingbonnet bolts.The Mark One valve is typically double top-stem guided andcompletely avoids contact between the plug and seat retainer.Many globe valve maintenance problems can be traced to cageguiding. The close metal-to-metal contact between the cage andplug often result in galling and sticking.The clamped-in seat and top-entry trim permits easy, quickmaintenance. Plus, with the Mark One valve’s high degree ofparts inter changeability, fewer inventory parts are required. Inaddition, the actuator is lighter, smaller and easier to handle thancomparable diaphragm actuators.The Valtek Mark One control valve is the industry choice for asimple, reliable, tough globe valve.

Valtek Mark One Control ValvesFCD VLENTB0001-02-AQ – 8/14Advantages and FeaturesAdvantagesDesign provides lower totallifetime costFeaturesHigh 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-face standardsTrim 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 many orientations and compensate forflange misalignmentReliable, predictable serviceStiff, high-thrust cylinder actuatorAccurate positioningHigh repeatabilityFaithful responseControlled, high-speed stroking action3flowserve.com

Valtek Mark One Control ValvesComponents4Figure 2: Mark One Control ValveFCD VLENTB0001-02-AQ – 8/14

Valtek Mark One Control ValvesFCD VLENTB0001-02-AQ – 8/14Body StylesFigure 3: Globe-style bodyFigure 4: Three-way BodyGlobe-style bodies feature smooth, streamlined, constant-areainternal passages with no pockets, permitting high capacity withminimum turbulence. They are designed with nearly constant wallthickness, providing lower weight and cost when manufactured inexpensive stainless or alloy steels.Three-way bodies are used for either combining or divertingservices. Due to Flowserve’s excellent parts interchangeability,a standard globe valve easily converts to three-way service withthe addition of a three-way adaptor, upper seat ring, two gaskets,three-way plug and longer bonnet flange studs.Figure 5: Angle-style BodyExcept for the body and 1.5-inch (DN 40) seat ring, the angle-styleMark One valve is completely interchangeable with the globe style – allother valve parts remain the same. For additional body protection, aventuri seat ring, extending to the outlet flange, is available.Figure 6: Steam-jacketed BodyThe steam-jacketed Mark One valve uses a standard globe stylebody with oversized, blind flanges for a full jacket or standardflanges for a partial jacket. The jacket is rated for 150 psig (10.3barg) and is equipped with a 0.75-inch NPT supply and drainconnection.flowserve.com5

Valtek Mark One Control ValvesFCD VLENTB0001-02-AQ – 8/14End Connections, Flanges and BoltingMark One body facings come standard as raised face for either separable andintegral flanges. To achieve better sealing with mating piping, the flange face ismachined with spiral grooved serration. Other optional facings include smoothface, flat face, ring-joint, large and small tongue, and large and small groove.Bonnet FlangeSeparable End FlangesBonnet ndardforvalvebodies 0.5- through 4-inch (DN 15 -100) in ANSI Class 150, 300 and 600 (PN16, 40, 100). With separable end flanges, an ANSI Class 600 (PN 100) body canbe adapted for ANSI Class 150, 300 or 600 (PN 16, 40, 100) service by simplychanging the end flanges.Separable flanges are usually furnished in carbon steel for maximum cost savings,although stainless steel can be specified if needed.Bonnet FlangeThe bonnet flange incorporates the same separable design as the end flanges andis normally manufactured in carbon steel; however, it can be specified in stainlesssteel when required.Bonnet Flange BoltingEnd FlangeANSI Class 150(PN16)Body ANSIClass 600(PN 100)Figure 7: Separable End and Bonnet FlangesAll sizes use studs and nuts that are furnished in 304 and 316 stainless steel,suitable for -423 to 1500 F (-253 to 816 C). These temperature limits are formaximum pressure permitted by ANSI B16.34, latest edition.Table 1: End ConnectionsEndConnectionRating 0016-100IntegralFlange- Steeland 900150-60016-1000.5-2415-600900-2500160-400Screwed (NPT)SocketweldButtweld6Valve S75.12ANSI Class 300 (PN 40)S75.15ANSI Class 600 (PN 100)Figure 8: End Flanges

Valtek Mark One Control ValvesFCD VLENTB0001-02-AQ – 8/14Gaskets and ClampsThe Mark One valve is designed with the bonnet and seat ringgaskets fully retained. Since the bonnet bottoms metal-to-metalin the body, the bonnet gasket compression is determined by thedepth of the gasket step on the bonnet, which is machined toprovide the required gasket compression.When the bonnet is fully installed, force is transmitted throughthe seat retainer to secure the seat ring in position. The body,seat retainer and seat ring are all machined to close tolerancesto provide the proper gasket compression. Unlike the bonnet,the seat ring does not always bottom in the body, allowing thissmall clearance to compensate for manufacturing tolerances andthermal expansion.Bonnet GasketSeat RingGasketFigure 9: Body GasketsTable 2: Gasket asket MaterialFlatPTFESpiral WoundSpiral WoundMaximum Gasket Temp0F0CMinimum Gasket Temp0F-2000C350177-130304 S.S./AFG750400-20-30316 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 0 F (4270 C) for oxidizing servie.Yoke ClampsThe actuator is typically attached to the Mark One body assemblywith two precision-cast, stainless steel yoke clamps. In somecases, however, the actuator is bolted directly to the bonnet.Each clamp has an inclined plane surface which, when boltedtogether, securely fastens the actuator yoke to the bonnet. Unlikeconventional threaded clamps, the clamp design permits easyremoval even under extremely corrosive conditions.Associated bolts and locknuts are supplied in plated carbon steel,although stainless steel is also available when required.YokeClamp7Figure 10: Yoke Clampflowserve.com

Valtek Mark One Control ValvesFCD VLENTB0001-02-AQ – 8/14Bonnet TypesStandard BonnetExtended BonnetCold Box Extended BonnetFigure 11: Mark One Bonnet TypesStandard BonnetGuardian II Formed Metal Bellows Seal BonnetThe Mark One bonnet is usually constructed of the same materialas the body and handles temperatures from -20 to 750 F (-30 to400 C). See Table 4 on page 9 for packing limitations.The Guardian II formed metal bellows seal can be used wheneverservice fluid leakage to atmosphere needs to be reduced to anabsolute minimum. The standard metal bellows seal is rated foroperation in processes ranging in temperature from -320 F to1100 F (-196 to 593 C) and pressures to 1100 psig (75.9 barg).Extended BonnetThe extended bonnet protects the packing from excessive heator cold, which may inhibit valve performance. The bonnet isconstructed of carbon steel for temperatures from -20 to 800 F(-30 to 427 C) and of 304 or 316 stain less steel for -150 to1500 F (-100 to 816 C).8The flexible metal bellows is typically constructed of Inconel 625and is also available in Hastelloy C-22.The Guardian II bellows seal allows for outside pressure tominimize bellows squirm, prolonging bellows life.Cold Box Extended BonnetGuardian Metal Bellows Seal BonnetThe cold box extended bonnet permits stagnated, moderatetemperature gas to form in the bonnet, which protects thepacking from the service fluid. Typically manufactured from 304or 316 stainless steel, it handles temperatures down to -423 F(-253 C). Standard construction consists of stainless steelbonnet flange and bolting.The Guardian metal bellows seal provides protection againstunwanted packing leakage to atmosphere in processes involvingcaustic liquids or gases.The compact, lightweight design of the Guardian bellows assemblymakes it ideal for services less than 650 F (343 C) and 310 psig(21.4 barg). The precision-formed bellows is available in Inconelor Hastelloy C materials.NOTE: Bellows seals are designed for special service conditionsand not to valve’s design class; therefore, complete and accurateservice conditions must be specified.

Valtek Mark One Control ValvesFCD VLENTB0001-02-AQ – 8/14Packing and GuidingPacking Box3.Two widely spaced stem guides, when used with the MarkOne’s large plug stem diameter, provide exceptional guiding.The upper stem guide also acts as a packing follower; thelower guide is situated close to the plug head for additionalguiding support, ensuring accurate alignment of plug andseat ring.4.Graphite-lined stainless steel guides provide superior guidingover wide temperature ranges and completely eliminateguide/stem galling. A variety of guides are available forvarious applications, including solid brass, Alloy 6 and glassfilled PTFE-lined stainless steel.Standard Valtek packing boxes are deeper than most conventionaltypes, providing the following advantages:1.2.The spacing between the wiper set and the main upperpacking set prevents contamination of the upper packing. Theupper set is positioned far enough away from the wiper setto avoid contact with any part of the plug stem that has beenexposed to the flowing medium. The wiper set is designed tominimize the amount of fluid on the plug stem.Bonnets are designed to permit a wide variety of packingcon figurations, including a double set of packing, withoutchanging bonnets.Table 3: ined SS***15000 F8160 C-3200 F-1960 CGlass filled300 F148.9 CUpperGuideMaximum Pressure1400 psig / 96.6 barg up to 2-in / DN 501000 psig / 69.0 barg 3-4 in / DN 80-100850 psig / 58.6 barg 6 in DN 150 & upUpperPackingSeat-325 F 1400 psig / 96.5 barg @ 60 F / 15.5 C-198.3 CSolid Bronze5000 F2600 C-4230 F-2530 CSame as bodySolid Alloy 615000 F8160 C-4230 F-2530 CSame as bodyTable 4: PackingBonnet TypeStandard**BonnetExtended**BonnetPacking MaterialService FluidTemperatureLimitationPTFE, PTFE/AFP andGlass-filled PTFE5000 F5000 F2600 C2600 CGraphite/AFP7500 F4000 CGraphite/AFP, Inconel wire0750 F*4000 C*Graphite***7500 F*4000 C*PTFE, PTFE/AFP andGlass-filled PTFE600 F3160 CGraphite/AFP12000 F6500 CGraphite/AFP, Inconel wire12000 F6500 CGraphite***15000 F8160 C0Cryogenic Extended Length**15, 18-inch (38, 46 cm)PTFE-3200 F-1960 C24, 27-inch (38, 46 cm)PTFE-423 F-2530 C0Lower GuideWiperPackingSet* Temperatures assume environmental temperature is less 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) handlestemperatures to 850 F (454 C).** ANSI B16.34 specifies acceptable pressure temperature limits for pressure retaining materials. Consult the factory for additional information.*** Do not use graphite above 800 F (427 C) in oxidizing service such asair or oxygen. The use of graphite packing may require over size actuatorsor heavier springs due to added friction.9flowserve.com

Valtek Mark One Control ValvesFCD VLENTB0001-02-AQ – 8/14Flow Characteristics, Trim TypesEqual PercentageTIC% FlowEqual percentage is the characteristic most commonly used inprocess control. The change in flow per unit of valve stroke isdirectly proportional to the flow occurring just before the changeis made. While the flow characteristic of the valve may be equalper centage, most control loops produce an installed characteristic, which approaches linear when the overall system pressuredrop is large relative to that across the ENTINHER50EqualPercentage050% Valve Stroke10050LinearTYPICAL% FlowLinear inherent characteristic produces equal changes in flow perunit of valve stroke regardless of plug position. Linear plugs areused on those systems where the valve pressure drop is a majorportion of the total system pressure drop.0100% FlowQuick-open50% Valve Stroke100RISTICRACTET CHANEREINHQuick-openQuick-open plugs are used for on-off service and are primarilydesigned to produce maximum flow INSLinear10050050% Valve Stroke100Figure 13: Flow CharacteristicsTrim TypesThree trim types are available. Standard full-area trim providesmaximum CV. Reduced trim is available in a wide variety of sizeswhen lower CV values and large bodies are required. Integral trimuses a special seat machined into the body and an oversized plugto provide additional CV beyond the capabilities of full-area trim.Mark One valves can be converted from one trim type to anothersince all seat rings and plugs with a given size and pressureclass are completely interchangeable. Integral trim is available byremoving the seat ring and by changing the plug.Full AreaReducedFigure 14: Typical Trim Types10Integral

Valtek Mark One Control ValvesFCD VLENTB0001-02-AQ – 8/14Standard Trim, Pressure-balanced lug SealsPlug VentPlugPlugPressurebalancedSleeveSeatRingFigure 15: Standard TrimFigure 16: Pressure-balanced TrimMark One valve trim is designed to avoid the difficulties associatedwith screwed-in seats and cage-guiding. The seat ring is clampedinto the body by the bonnet and seat retainer; thus, removal of theseat is easy even under extremely corrosive conditions.In high pressure drop applications, pressure-balanced trim is usedto reduce the thrust necessary to stroke the plug by reducing thetrim off-balance area. Because the pressure-balanced plug fitsclosely to the retainer, this trim should only be used in generallyclean services.Unlike cage-guided trims that easily gall and stick, Mark Oneplugs are double-stem guided, avoiding contact between the seatretainer and plug. Because no contact is made with the plug, theretainer can be constructed of stainless steel rather than costlyhard 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 better noisecontrol in standard Mark One valves.Metal SeatsMetal seated valves handle Class IV shutoff (ANSI B16.104,1976 – FCI 70-2). This class calls for maximum permissible seatleakage of 0.01 percent of rated valve capacity. All Valtek controlvalves are seat-leak tested after assembly and are substantiallylower in leakage than called for by this class. This exceptionalseat tightness is obtained by aligning the seat ring with the plugduring assembly. Additional seat tightness using metal seats isavailable as an option.Flow direction is under-the-plug for fail-closed and over- the-plugfor fail-open. The seal area less the stem area is designed to beslightly larger than the seat area; therefore, the plug is off-balancedto close for flow under the seat and off-balanced to open for flowover the seat.Soft SeatsThe Mark One soft seat is used in applications requiring ANSIClass VI ‘bubble-tight’ shutoff. Its design consists of an elastomersandwiched between two metal pieces. The assembled softseat is interchangeable with the hard seat for a given size andpressure rating. Inserts are often constructed of PTFE; therefore,maximum temperature 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-pressure applications.Table 5: Standard Seal Temperature RangesPTFE SleeveInsert Retainer-3200 F (-1960 C) @ full rating or 3000 F(1500 C) @ 150 psig (10.3 barg)Rene 418000 to 16000 F4270 to 8710 CSpring-energized PTFE-3650 to 5750 F-2210 to 3020 CViton-40 to 437 F-400 to 2250 C00Soft Seat RingInsertFigure 17: Typical Soft Seat Configurationflowserve.com11

Valtek Mark One Control ValvesFCD VLENTB0001-02-AQ – 8/14Trim Materials, DataTable 6: Material Harness RatingsStandard plug and seat ring material is 316 stainless steel,except special alloy bodies where trims are funished in the samematerial as the body. A wide variety of services are successfullyhandled by stainless steel trim parts. Neverthless, a general ruleis for temperatures above 600º F / 316º C. Alloy 6 is stocked formany valve trim parts. This material offers a good combination ofrelative hardness and corrosion resistance. Special alloys, such asAlloy 20, Hastelloy C and Monel, are also available.Trim MaterialHardnessRockwell CCorrosionResistance*316 S.S.8ExcellentAlloy 644Good to Excellent416 S.S.40Fair440C S.S.56Fair17-4 PH40ExcellentColmonoy45-50Fair to GoodTungsten Carbide72Good on BasesPoor on Acids*General rule only. Check specific applicationTable 7: Standard Unbalanced Valve / Actuator DataValve Size12Rating ClassFull Area TrimSizeSeat AreaStem DiameterStem 00-15002500150300-60090