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Answers for energy. Siemens Gas Turbine SGT6-5000F Application Overview

Siemens Gas Turbine SGT6-5000F

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Siemens Gas Turbine SGT6-5000F

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  • Answers for energy.

    Siemens Gas Turbine SGT6-5000FApplication Overview

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    Siemens Gas Turbine

    SGT6-5000F

    Key:

    1. Generator coupling2. Thrust bearing3. Journal bearing4. Inlet air duct5. Inlet cylinder6. Variable inlet guide vane7. Compressor rotating blades8. Fixed compressor end support9. Compressor diaphragms with

    labyrinth seals10. Compressor cylinder with

    borescope access11. Compressor thru-bolt12. Compressor bleed manifolds13. Compressor, combustor and

    turbine cylinder

    14. Fuel nozzles15. Combustor baskets16. Combustor transitions17. Torque tube/air separator18. Engine horizontal joint19. Turbine disc thru-bolts20. Individual first-stage stationary vanes21. Turbine multivane diaphragms22. Turbine discs23. Turbine rotating blades24. Turbine roll-out blade rings25. Blade path thermocouples26. Flexible turbine end support27. Exhaust expansion joint28. Exhaust cylinder29. Exhaust diffuser inner cone

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    Table of contents:

    Application overview ........4

    Service and support ..........6

    Power Diagnostics services ............................7

    SGT6-5000F gas turbine ....8

    Scope of supplydefinitions ......................13

    SGT6-PAC 5000Fpower plant ....................14

    Auxiliary packages ..........16

    SGT6-PAC 5000F plantarrangement diagram ....19

    SGT6-PAC 5000F simple cycle performance ..........20

    SGT6-PAC 5000Ftechnical data ................22

    SCC6-5000F combined cycle plants ....................23

    SCC6-5000F plant arrangement diagrams ....26

    SCC6-5000F plant performance ..................28

    Integrated gasification combined cycle plant application......................31

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    Siemens Gas Turbine engine SGT6-5000F

    The advanced technology of the SGT6-5000F* gas turbine continues to satisfy the worldwide needs of thepower generation marketplace for 60 Hzprojects. Siemens introduced the firstunit in the W501 series in 1968. Sincethat time over 560 units of Siemens GasTurbines (SGTTM) have been sold.Siemens evolutionary design philosophymaintains continuity by building on our proven gas turbine technology. Toattain high engine reliability, upgradesor new engine designs are based ontechnologies proven by engine operationor by extensive component testing.

    The SGT6-5000F gas turbine exemplifiesthis evolutionary process. This SGT6-5000Fgas turbine combines the efficient,proven design concepts of the W501D5with the addition of advanced coolingtechnologies and improved compressorconstruction. The advanced coolingtechnologies allow higher flow path gas temperatures while keeping metaltemperatures at the level of previousengines. The technology upgradesapplied to the SGT6-5000F gas turbinehave resulted in an engine with a ratedoutput that is among the highest of theF class gas turbines. The SGT6-5000Fgas turbine fleet has achieved over 3.4million hours of reliable operation andnet combined cycle efficiencies of 57%.

    This gas turbine is ideally suited for simplecycle and heat recovery applicationsincluding Integrated GasificationCombined Cycle (IGCC), cogeneration,combined cycle and repowering. Flexible fuel capabilities include naturalgas, LNG, distillate oil, syngas and otherfuels, such as low- or medium-Btu gas.

    The low emissions SGT6-5000F gas turbine engine consists of a 16-stageaxial-flow compressor, a combustion system composed of 16 can-annularcombustors and a 4-stage turbine.Packaged with the generator and otherauxiliary modules the SGT6-PAC 5000F**power generation system provides economical power for peaking duty,operational flexibility and load followingcapabilities for intermediate duty, whilemaintaining high efficiencies for contin-uous service. Regardless of the applica-tion, the SGT6-5000F gas turbine is thebasic building block for a wide variety of power generation systems.

    Siemens Simple Cycle applications

    The Siemens Simple Cycle (SSCTM) SGT6-PAC 5000F power plant, nominallyrated at 196 MW, is a self-contained,electric power generating system suitedfor simple cycle applications. The designof the SGT6-PAC 5000F includes over 50 years of experience in gas turbinetechnology and power plant design.These following proven features, incorporated into the SGT6-PAC 5000Fpower plant include:

    Factory assembled fuel, auxiliary, lubricating and electrical packages

    Walk-around enclosures for turbine and auxiliary packages

    Microprocessor-based distributed control system

    Air-cooled generator

    Normal start time - 29.5 minutes to base load

    Optional fast start - 10 minutes to150 MW.

    * SGT6-5000F gas turbine engine was formerly called theW501F.

    ** SGT6-PAC 5000F power plant was formerly called theW501F Econopac.

    SGT6-5000F application overview

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  • Siemens Combined Cycle applications

    Siemens has more than three decades of experience in combined cycle plantdesign. Our first combined cycle experi-ence came in the early 1960s with theinstallation of the West Texas Utilities plantusing a W301, a 30 MW gas turbine. Thesecond generation of combined cycleplants were the PACE (Power at CombinedEfficiencies) plants introduced in the early1970s. The PACE plants used an earlierW501 model, the W501B, as their primemover and were pre-engineered, stan-dardized combined cycle plants.

    The Siemens Combined Cycle (SCCTM)SCC6-5000F plant*** design (as shownin Figure 1) is built on the strong knowl-edge base derived from these previousdesign efforts. With 1x1 (~293 MW), 2x1 (~591 MW) and 3x1 (~885 MW) configurations, the SCC6-5000F familyof combined cycle plants is sized to meet the various base and cyclic loadrequirements of utilities, independentpower producers (IPPs) and merchantplant operators. The development ofthese designs allows for cost-effectiveplants that require minimal project specific engineering.

    Project capabilities

    Siemens is experienced in producing suc-cessful power projects. Our comprehen-sive scope of capabilities includes:

    Total turnkey power plants

    Integrated project management

    Plant engineering and design

    Plant permitting assistance

    Equipment installation

    Plant operation and maintenance.

    When we take responsibility for a project, or any portion of it, an integrated projectmanagement approach is applied to thetask. The planning techniques used areamong the most advanced in the industry.Project goals are clearly developed andwell communicated. Work packages arecreated which include drawings, materiallists and sign-off sheets. Personal account-ability means a personal commitment to quality. Siemens has achieved animpressive record for building plants on schedule and within budget.

    *** SCC6-5000F combined cycle power plant was formerlycalled the W501F combined cycle plant.

    SGT6-5000F application overview

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    Figure 1 - SCC6-5000F combined cycle plant design

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    A global network for service and support

    Siemens is equally committed to providingcomprehensive service programs thattruly support and optimize the perform-ance of your equipment. We begin withtechnical assistance provided during theinstallation and start-up of your equip-ment and continue with a multitude ofservice options. These include turnkeymaintenance inspections, technical fieldassistance, modernizations and upgrades,repair and refurbishment and controlsystem service and upgrades.

    We have established a powerful andresponsive service network with more than4,000 field engineers and technicians inregional service offices around the globe.So wherever you are, wherever your plantis located, we speak the language, weknow the market and we are availablewhen you need uswith rapid-responsesolutions that translate into measurablebenefits for you.

    Total Maintenance Services

    Our comprehensive service approach alsomeans that we have the ability to trackunit trends in our global fleet throughleading edge diagnostics technology toensure maximum unit performance andavailability. Total Maintenance Services(TMS) is a structured outage planning,implementation and lessons-learnedprocess. It enables our customers toreceive regular notifications of the latest engine design improvements andupgrades as well as notices regardinginspection and maintenance activities.Pre-outage planning is a standard featureto ensure preparedness by identifyingnecessary parts, modifications andupgrades that are available, new trainingprograms, addressing customer questionsand concerns, and offering a compre-hensive scope of recommendations.

    By analyzing data and trends from the entireoperating fleet, we can identify and preventissues before they impact your plant perform-ance. The constant flow of information anddocumented pre-outage planning initiativesenable our customers to be better informedand prepared for a more efficient and timelyoutage that meets their goals of unit reliabil-ity, outage duration and budget.

    Service programs

    Our Service Agreements link perform-ance with customer objectives, providingturnkey outage services as well as partsand repairs for scheduled and unsched-uled maintenance.

    This performance-based contractapproach provides incentive for bothparties to benefit from on-time comple-tion, high-quality maintenance, projectmanagement and advanced, remote monitoring and diagnostics systems. A dedicated program manager is on-callto provide support and a dedicated teamof locally based district managers, homeoffice personnel and factory-trainedtechnicians understand and are closelyaligned to your objectives. Our flexibleservice approach enables us to workwith you to create a service programthat truly meets your requirements.

    We want to develop an ongoing partner-ship to help ensure your projects long-term success. We are committed to serving our customers well after plantcommissioning. That is why we offercomprehensive service options, backedby a global network of resources, to support your equipment throughout its entire life-cycle.

    Service and support

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  • Power Diagnostics

    Siemens has provided diagnostic systemsdesign and implementation since the early1980s. Whether you are a plant owner oroperator, our Power Diagnostics servicescan help you maximize your plant perform-ance, availability and profitability.

    Your power business is unique; accordingly,your business requirements demand themost innovative and effective solutionsavailable. We meet these challengingrequirements with one of the most effec-tive monitoring and diagnostics servicesavailable to power plant owners. Our PowerDiagnostics approach keeps your plant con-nected to our vast engineering expertise.Data acquired by acquisition systems istransmitted to the Power DiagnosticsCenter to be analyzed and processed byspecialists and engineers. This engineer-ing knowledge, combined with the useof sophisticated tools, provides trendingand analysis capabilities to address abroad range of operating needs specificto each customer. This approach facilitatescontinuous improvement of our solutionsto help you enhance your plants availabilityand reliability.

    Our Power Diagnostics Centers in theUnited States and Germany are moni-tored around the clock with experiencedprofessionals who understand the com-plexity of your turbine systems and thedemands placed on them. These highlyskilled and trained engineers recognizethe importance you place on keepingyour plant on-line to meet businessdemands. If an abnormal trend is detected,your data will be analyzed, compared to our vast historical operating fleetdatabase, and presented in an under-standable manner to your plant staff fortimely trend assessment. Analysis resultsalso can help you to schedule outageswith more precision. If required, quick-response technical resources also can bedispatched for on-site problem resolution.

    To help you optimize your plant operat-ing availability and enhance your bottomline, Power Diagnostics is invaluable inassisting with the detection of impend-ing operational problems, thereby help-ing to minimize unplanned outages andmaximize power generation availability.

    Power Diagnostics services

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  • General description

    Designed for both simple and combinedcycle applications, the SGT6-5000F gas turbine can operate on conventional gasturbine fuels and a wide range of alter-nate fuels subject to review by Siemens.The gas turbine consists of a 16-stage,high efficiency axial compressor, combus-tion chamber equipped with 16 Dry LowNOx (DLN) emissions or conventional combustors arranged in a circular arrayaround the engine centerline, and a 4-stage reaction type turbine. The gas turbine is coupled directly to the genera-tor at the compressor end.

    Ambient air is drawn through the inletmanifold and inlet casing into the com-pressor. It is pressurized to approximately 16 atmospheres and guided into the combustors, where it is mixed with fueland ignited, raising the temperature of the mixture. The compressed and heatedmixture (gas) then expands through theturbine, dropping in pressure and tem-perature as the heat energy is convertedinto mechanical work. A portion of thepower developed by the turbine is used for driving the compressor, with the balance of power used to drive the generator. Expanded gases are thenexhausted into the atmosphere through an exhaust stack for a simple cycle appli-cation or through a Heat Recovery SteamGenerator (HRSG) and exhaust stack in acombined cycle application.

    Design features

    SGT6-5000F gas turbine features, such as cold-end generator drive, two-bearingdesign, horizontally split casings, can-annular combustors and tangential strutsupports have been used in this gas turbine family since the early 1950s.

    The axial exhaust concept, introduced in1970 on the W501AA, improves performanceand provides greater flexibility for multipleunit plant arrangements especially whenapplied to combined cycle power plants.

    Design features summary:

    A two-bearing rotor used to simplify alignment

    Bearings that operate at below atmos-pheric pressure to prevent shaft seal leakage

    Readily accessible bearings that can beremoved and replaced without liftingthe gas turbine covers

    Compressor blades that can be removedfor inspection and reinstalled withoutdisturbing blades in other rows andwithout removing the rotor from itscasing

    Low temperature environment of theexhaust bearing permits the use of less expensive and readily available lubricating oil

    Individual turbine blades that can beremoved for inspection or replacementwith the rotor in place and without disturbing other blades

    Compressor diaphragms and turbineblade rings that can be taken out forinspection or be replaced with the rotorin place

    Field balancing, two end and one cen-ter balance planes are easily accessible

    Multiple boroscopic inspection ports inthe compressor and turbine flow pathsto permit inspection of the bladingwithout lifting covers

    Turbine supports for free expansionand contraction due to temperaturechanges without disturbing the shaftalignment

    Cooling circuits designed to protect thegas turbine parts from the high temper-ature gas stream for better reliabilityand longer life

    A tangential strut support system forthe turbine-end bearing a Siemenspatented feature for maintaining thebearing on centerline for all conditionsof load and temperature.

    SGT6-5000F gas turbine

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  • Major assemblies

    Casings

    Engine casings are horizontally split tofacilitate maintenance with the rotor inplace. Inlet casings are cast from nodulariron or fabricated from cast steel. The compressor section casings are cast steelwhile the combustor, turbine and exhaustcasings are alloy steel.

    Eight radial struts support the inlet bearing housing while six tangential struts support the exhaust-end bearinghousing. Airfoil-shaped covers protect the tangential struts from the blade pathgases and support the inner and outer diffuser cones.

    Tangential struts maintain alignment of the bearing housing by rotating it, asrequired, to accommodate thermal expan-sion. Individual inner casings (blade rings)are used for each turbine stationary stageand can be readily replaced or serviced with the rotor in place. Similar blade ringsare in the compressor for stages seventhrough sixteen. The blade rings have athermal response independent of the outer casing, thereby permitting the blade rings to remain concentric to therotor. This allows for a minimum clearancebetween rotating and stationary airfoils in order to increase flowpath efficiency.

    Rotor assembly

    The rotor consists of the compressor and turbine rotor components bolted togetherand supported by two tilting-pad bearings. A direct lubricated, double acting thrust bear-ing located at the compressor end of the gasturbine accommodates engine thrust. Thecompressor rotor is comprised of multiplediscs equipped with load carrying keysbetween discs, aligned using a spigot fit andclamped together by 12 through bolts.

    The turbine rotor is made up of interlockingdiscs using CURVIC couplings that are held together by 12 through bolts. The CURVIC couplings consist of mating curved

    teeth that are located around the circumfer-ence of adjacent disc faces, which interlockand provide precise alignment and torquecarrying abilities. This proven turbine rotordesign has accrued millions of hours of reli-able service in all sizes of our gas turbines.

    Any turbine or compressor blade can beremoved for inspection and replaced without lifting the rotor.

    Air inlet system and compressor

    The air inlet system, consisting of the inletfilter, inlet silencer and associated duct-work, delivers air to the compressor. Thecompressor is a 16-stage axial flow designand achieves a 17-to-1 pressure ratio.Inter-stage bleeds for starting and coolingflows are located at the 6th, 10th and 13thstages. The compressor is equipped withone stage of variable inlet guide vanes toimprove the compressor low speed surgecharacteristics and part load performancein combined cycle applications.

    The compressor blade path design is basedon an advanced three-dimensional flow fieldanalysis computer model. All rotor bladesincorporate an improved root design thathas flat contact faces (as do the turbineblade roots), which allows the blades to beremoved in the field with the rotor in place.The blades of the first six stages are 17-4 pH(17% Cr precipitation hardened stainlesssteel). Rows seven through sixteen bladesuse AISI 616 stainless steel.

    Each stage of stationary airfoils consists oftwo 180 diaphragms for easy removal. Aninner shroud sealing system is used on theSGT6-5000F gas turbine. The seals are sup-ported by machined seal rings, which can be removed to facilitate inspection andmaintenance of shrouds and seals. One rowof exit guide vanes is used to direct the flowleaving the compressor. Stationary airfoilsand shrouds utilize corrosion and heat-resistant stainless steel throughout.

    Compressor rotating and stationary airfoilsare coated to improve aerodynamic perform-ance and provide corrosion protection.

    SGT6-5000F gas turbine

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    Combustion system

    The combustion system consists of 16 can-annular, dry low emissions (25 ppm or 9 ppmNOx systems are available) or conventionalcombustors.

    The presence or absence of flame and theuniformity of the fuel distribution betweencombustors are monitored by thermocoupleslocated downstream of the last stage turbineblades. These can also detect combustor mal-functions when at load. Ultraviolet detectorsare used to sense ignition during starting.

    Transition ducts, one for each combustor,direct the hot gases from the combustors tothe turbine blade path. The transitions are air-cooled and the same design is used in bothsimple and combined cycle applications.

    Turbine section

    The turbine design of the SGT6-5000F gasturbine maintains moderate aerodynamicloading by the use of a 4-stage turbine.Furthermore, improvements in aerodynamicairfoil shapes have been made possible byusing a fully three-dimensional flow analysiscomputer model. A sophisticated airfoildesign approach was utilized to target highaerodynamic efficiency.

    The 1st and 2nd stages on the turbine rotorcontain 72 and 66 freestanding blades,respectively. The 3rd and 4th stages contain112 and 84 blades, which incorporate inte-gral Z-tip shrouds. The shrouding of bladesallows increases in mass flow and thus anincrease in the power output. The shroudedblade design prevents flow induced non-synchronous vibration due to aero-elasticinteraction between blade structure and flow.

    The 1st and 2nd stage rotating blades areprecision cast of equiaxed IN-738. The 3rdand 4th stage rotating blades are precisioncast of equiaxed CM-247. All rows have longblade root extensions to minimize the stressconcentration factor that results when loadis transferred between cross sections of different size and shape. Roots are multipleserration type with four serrations used onthe first two rows and five serrations on thelast two stages.

    The 1st turbine stationary row consists of 32 precision-cast, single-vane segments ofECY-768 alloy coated with thermal barriercoating (TBC) for improved thermal resist-ance. Consistent with previous proven W501designs, 1st row single vanes are removable,without lifting any covers, through accessports in the combustor shell. Inner shroudsare supported from the torque tube casingto limit flexural stresses and distortion, thusmaintaining control of critical 1st row vaneangles. In the 2nd turbine stationary row,there are 24 two-vane segments precision-cast of ECY-768 alloy, which are also treatedwith TBC. The 3rd turbine stationary row consists of 16 three-vane segments and the4th turbine stationary row consists of 14 four-vane segments. Both are precision castof X-45.

    Each row of vane segments is supported in a separate blade ring, which is keyed andsupported to permit radial and axial thermalresponse independent of possible externalcylinder displacements. Segmented isolationrings support the vane segments. Ring segments located over the rotating bladesform the flow path outer annulus. Isolationand ring segments both act to limit thermalconduction between the flow path and theblade ring, thus mitigating blade ring clear-ance changes in the turbine section. Theinterstage seal housings are uniquely support-ed from the inner shrouds of rows 2, 3 and 4vane segments by radial keys. This permitsthe thermal response of the seal housings tobe independent of the more rapid thermalresponse of the vane segments.

    Cooling system

    Comprehensive cooling methods enable theSGT6-5000F gas turbine to operate at highperformance firing temperatures while usingconventional materials.

    Compressor bleed air from the 13th, 10thand 6th stages are used to provide coolingair to turbine blade ring cavities at the 2nd,3rd and 4th stages, respectively. This supplyof bleed air also cools the 2nd, 3rd and 4thstage vanes and ring segments and provides

    SGT6-5000F gas turbine

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    cooling air for the turbine interstage disccavities to shield the interstage seals anddisc faces from hot blade path gases.

    Direct compressor discharge air is used tocool the 1st row vane. The 1st row vanecooling design uses state-of-the art conceptswith three impingement inserts in combina-tion with an array of film-cooling holes and a trailing edge pin-fin system. Showerheadcooling is used at the leading edge of the 1st row vane, while film cooling is used atselected pressure and suction side locations.This limits vane wall thermal gradients andexternal surface temperatures, while provid-ing an efficient re-entry for spent cooling air.Pin-fins, used successfully for the first timeon the W501D5 1st row vane, are used toincrease turbulence and surface area, therebyoptimizing the overall trailing edge coolingeffectiveness. (See Figure 2.) The design ofthe 1st row vane is such that the Low CycleFatigue (LCF) design criteria is satisfied bycontrol of wall thermal gradients.

    For the 2nd row vane, 13th stage compres-sor bleed air is ducted directly to the twininsert system. The 2nd row vane cooling is aless complex version of 1st row vane cool-ing. It uses twin impingement inserts withfilm-cooling holes and a trailing edge pin-fin

    system. Film cooling is used at one locationon the suction side and at the exit of the aftinsert on the pressure side.

    Compressor bleed air from the 10th stage isused to supply cooling air to the 3rd stageblade ring cavity. Cooling air is directed tothe inlet cavity of a three-cavity multipassconvective-cooled vane airfoil. Leading edgecavity flow also supplies the interstage sealand cooling system, while the third pass cavity exits at pressure side gill holes on the vane surface. The 4th stage vane isuncooled, but does transport 6th stage com-pressor bleed air for the 4th row inter-stageseal. (Figure 3 depicts the cooling system.)

    Rotor cooling air is extracted from the com-bustor shell. The air is externally cooled andreturned to the torque tube seal housing tobe used for seal air supply and for cooling ofthe turbine discs and 1st, 2nd and 3rd stageturbine rotor blades. This provides a blanketof protection from hot blade path gases.

    The 1st stage blade is cooled by a combina-tion of convection techniques via multipassserpentine passages and pin-fin cooling in the trailing edge exit slots. (See Figure 4,page 12.) Air supply for blade cooling is high-pressure compressor discharge air that hasbeen cooled and returned to the turbine rotorvia four supply pipes in the combustor shell.Cooling air flows outward through threeslots in the root and is conveyed radiallythrough the blade shank. Showerhead filmcooling is used for the leading edge region.The 2nd row rotor blade is also precision castand is cooled by a combination of convection

    SGT6-5000F gas turbine

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    4th Stage Cooling

    3rd Stage Cooling

    2nd Stage Cooling

    Rotor CoolingHeat ExchangerSGT6-5000F

    Second Stage Cooling Circuit

    Figure 3 - Turbine cooling air system

    Figure 2 - Row 1 vane cooling

    Leading edgeShowerheadfilm cooling

    Film cooling

    Protective + thermalbarrier coatings

    Vane impingement cooling inserts

    Pin-fin coolingtrailing edge

    Outer shroud filmand impingementcooling

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  • SGT6-5000F gas turbine

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    techniques via serpentine passage andpin-fin cooling in the trailing edge exitslots. The 3rd row blade is precision castwith single pass convective cooling holes.

    The cooling system maintains the NiCrMoVturbine discs at a temperature sufficient tokeep the disc below the creep range.

    Exhaust cylinder section

    The exhaust cylinder fabrication is com-posed of the bearing housing, inner andouter cones of the exhaust diffuser andouter case, all joined together by meansof a strut system. The strut system con-sists of six bearing struts equally spacedaround the circumference but positionedtangentially with respect to the bearinghousing.

    These struts extend from the bearinghousing to the outer case. In the hot gassection of the exhaust diffuser, the bear-ing struts are shielded inside another setof struts, which are hollow and serve assupports for the exhaust diffuser cones.Thus, the bearing struts are protectedfrom the hot exhaust gas by envelopesof cooler air around them. This results ina strut system that is less sensitive totransient temperatures. Growth of theouter case and struts is accommodatedby bearing housing rotation.

    The system provides a low stress, rigidsupport, capable of holding the bearingon center for variations of load and temperature.

    Axial exhaust manifold section

    The exhaust manifold section consists ofthe exhaust manifold, expansion jointwith flow liner and exhaust transition.The exhaust gas flows through the mani-fold and flow liner into the transitionand is then discharged into the stack.

    The manifold acts like a muffler in whichthe flow is slowed down without becom-ing excessively turbulent. This flow stabi-lization further improves the gas turbineperformance. All parts of the exhaustsystem section, with the exception ofthe expansion joint, are fabricated froma high strength, low alloy steel.

    The exhaust manifold is composed ofone outer and inner cylinder heldtogether by means of two hollow struts.The outer cylinder has the shape of atruncated cone. The inner cylinder, inconjunction with the inner cone of theexhaust diffuser, forms an enclosedchamber around the gas turbine center-line. An access passage to this chamberand a channel for the pipe and conduitlines going to the bearing area are provided through the hollow struts.

    The manifold is connected to theexhaust transition by means of anexpansion joint made from a high tem-perature-resistant material. The expan-sion joints primary function is to accom-modate the axial growth of the unit dueto thermal expansion and to prevent anyexternal load from being imposed uponthe exhaust manifold.

    The axial exhaust configuration is ideallysuited for waste heat recovery applica-tions such as combined cycle, cogenera-tion and repowering.

    Pin-fin cooling

    Multipass serpentinepassages

    Figure 4 - Row 1 blade cooling

    Showerhead film cooling

    Film cooling

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  • Scope of supply definitions

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    General description

    The SGT6-PAC 5000F plant is designedto provide the user with a completepower generating system. Componentsand subsystems are selected to form acompact plant housed within enclosures.

    The SGT6-PAC 5000F plant featuresmodular construction to facilitate ship-ment and field assembly. Subsystems aregrouped and installed in auxiliary modules.Each module of the SGT6-PAC 5000Fplant is factory assembled to the extentpermitted by shipping limitations to minimize field assembly. Pipe rackassemblies that provide interconnectingpiping between the standard modulesare supplied, eliminating the need forextensive piping fabrication during construction.

    The basic bill of materials for a SGT6-PAC 5000F plant typically includesthe following equipment and assemblies:

    SGT6-5000F Gas Turbine

    Open air-cooled generator

    Brushless excitation and voltage regulator system

    Starting package

    Electrical package

    Lubricating oil system package

    Instrument air system

    Hydraulic oil system

    Gas fuel system

    Inlet air and exhaust gas systems

    Compressor water wash package

    Piping packages

    Cooling systems

    Fire protection

    Voltage transformer and surge cubicle.

    Optional Equipment:

    Auxiliary transformer

    Isolated phase bus

    Evaporative cooling system

    Dual fuel combustion system

    Liquid fuel system

    Totally Enclosed Water-to-Air-Cooled(TEWAC) Generator

    Hydrogen-cooled generator

    Water injection package (supplied with liquid fuel system for NOx control).

    SGT6-PAC 5000F power plant

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    Generator

    The open air-cooled (OAC) SiemensGenerator (SGenTM) is equipped with acooling air filter, silencers, inlet andexhaust ducting, brushless exciter, acousti-cal enclosure, and necessary instrumenta-tion. The main three-phase terminals arelocated on top of the acoustical enclosureat the excitation end of the generator forisolated phase interface. Internal cooling isprovided via shaft-mounted axial blowers,which direct filtered ambient air throughthe generator's major internal compo-nents. A solid coupling connects the generator to the compressor at the coldend of the gas turbine.

    Totally enclosed water-to-air-cooled(TEWAC) (as shown in Figure 5) or hydro-gen-cooled generators are also options.

    Generator cooling system

    For open air-cooled generators, the cooling air is drawn into the generatorthrough a pad type filter and a silencingsection contained in the inlet duct. Thecooling air is forced through the generatorvia shaft-mounted blower fans located oneither end of the generator shaft. As theforced air passes through the generator'smajor internal components, the heat isabsorbed into the air and exhaustedthrough the exhaust duct.

    When selected, a TEWAC system provides aclosed cooling air circuit. Cooling water iscirculated through tube banks to exchangeheat energy between the closed circuit gen-erator cooling air and water. The internalactive cooling paths, including the shaft-mounted blowers, are identical in both OAC

    and TEWAC designs. Cooling water is sup-plied by a fin-fan cooler or from a plantcooling water system.

    Brushless excitation and voltage regulator system

    The brushless exciter and voltage regulatorsystem functions to supplies generator fieldexcitation and controls the output of the ACgenerator terminal voltage. The brushlessexciter has a shaft-mounted rotating arma-ture and diode wheel. The voltage regula-tor supplies the stationary DC field to thebrushless exciter, either under automatic ormanual control. A static excitation systemis an option.

    Starting package

    The base starting system is a modular pack-age, with a fabricated steel bedplate and asteel enclosure for outdoor installation. The starting system includes an AC electricmotor, a torque converter with chargingpump, a turning gear, a turning gear motor,a clutch and associated instrumentation.The welded steel, all-weather enclosure (for outdoor application) is complete withaccess stairs, a door and a maintenanceplatform. Louvered openings on the enclo-sure provide natural ventilation.

    An optional static starting system is avail-able for simple cycle applications. The staticstart package includes a static frequencyconverter, a static excitation system, a two-speed turning gear (with a DC motor forslow spin and AC motor for acceleration to120 rpm), a clutch and associated instru-mentation. The static starting system isused when the fast start option, (150 MWin 10 minutes) is selected.

    The starter package (whichever utilized)provides breakaway torque for initial rotation of the turbine generator, and thetorque necessary for acceleration to self-sustaining speed. The starting system dis-engages once the unit reaches self-sustain-ing speed. During cool-down periods, theturning gear, a component of the startingpackage, provides for a slow roll of thecombined turbine and generator rotor.

    SGT6-PAC 5000F power plant

    15

    Figure 5 - TEWAC generator

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 16

  • 25

    Electrical package

    The electrical package contains equipmentnecessary for sequencing, control andmonitoring of the gas turbine and genera-tor. This includes the gas turbine controlsystem, motor control centers, generatorprotective relay panels, voltage regulator,fire protection system, battery and batterycharger. The batteries are in an isolatedsection of the package and are readilyaccessible from the outside. RedundantHVAC units are provided in the electricalpackage to ensure a clean environmentfor the temperature sensitive electricaland control equipment.

    Lubricating oil system package

    The lube oil package is a factory manufac-tured weather-resistant skid for the lubri-cating oil system. The lubrication systemprovides clean, filtered oil at the requiredtemperature and pressure for lubricatingbearings of the gas turbine, generator andstarting package. The lube oil packageincludes a lube oil reservoir, which pro-vides a mounting base for the followinglube oil system components:

    Main and alternate AC motor-drivenpumps

    Emergency DC motor-driven pump

    Vapor extraction blowers

    Duplex filter assembly

    Accumulators.

    The lube oil cooler assembly is located ontop of the lube oil package roof. The lube oilsystem is supplied complete with intercon-necting piping, valves and instrumentation.

    Instrumentation air system

    The turbine enclosure houses the com-pressed air reservoir and a pressure switchand gauge panel. The pressure switch andgauge panel contains all of the requiredpressure switches, gauges, regulating andsafety valves, air filters and desiccants.These components clean, dry, control,monitor and direct the instrument air tovarious valves and instruments. For com-bined cycle installations, the most efficient

    source of compressed air is typically theplant service air compressors. For simplecycle installation, an optional reciprocatingair compressor can be provided.

    Hydraulic oil system

    A Hydraulic Oil Power Unit (HPU) is sup-plied when the engine is equipped with aDLN combustion system. The HPU provideshigh pressure hydraulic oil to operate thegas fuel stage throttle valve and the inletguide vane actuators. The HPU is a self-con-tained unit mounted on a fabricated steelskid assembly and is located outdoors adja-cent to the gas turbine enclosure and themechanical package enclosure.

    The major components are:

    Stainless steel fabricated oil reservoir

    AC motor-driven high pressure chargepumps; fully redundant (2 x 100%)mounted and driven by the high pressure pump motor spindle shaft

    Hydraulic oil cooler, radiator type fan

    Filter (100% redundant duplex) hous-ings assembly

    Safety relief valves, pressure regulatingvalves

    Hydraulic accumulators

    Electric immersion heaters

    Instrumentation for local and remotemonitoring of pressure and temperature

    Interconnect tubing assemblies (stainless steel).

    Gas fuel system

    The principal components of the gas fuelsystem are located inside the turbineenclosure. For the base unheated fueldesign, the fuel filter/separator is installedoutdoors adjacent to the gas turbineenclosure. The piping assemblies andvalves are supplied as spool sections forfield erection. The major components ofthe base fuel system include:

    Fuel filter/separator system

    Fuel throttle valves for each fuel stagewith associated instrumentation

    Overspeed trip and shut off valve(s)

    Auxiliary packages

    16

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 17

  • Main pressure control valve and startpressure regulating valve

    Vent valve

    Fuel flow monitoring orifices withassociated instrumentation.

    Instrumentation to monitor the criticalparameters is centralized and mountedon a fuel control panel located inside theturbine enclosure. Pressure gauges tolocally monitor the fuel pressure are typi-cally located on this panel. Field installedinter-connecting piping assemblies thatdirect the fuel to the turbine-mountedfuel manifolds are supplied.

    For the optional heated fuel design, anadditional filter/separator for the pilot stageand a pilot overspeed trip/shut off valve aresupplied. The pilot filter separator is alsolocated outdoors adjacent to the turbineenclosure.

    The heated fuel option is typically appliedin combined cycle applications. The fuel isheated using a low energy water sourcethus utilizing energy to improve the netcombined cycle efficiency.

    Liquid fuel system (optional)

    For liquid fuel applications (either dual or single fuel), a liquid fuel system is sup-plied. The liquid fuel system consists offactory-assembled components, includingan AC motor-driven fuel pump, a suctionside duplex fuel filter with transfer valve,and a control valve, installed on a bed-plate. Interconnecting piping to this gasturbine is also included.

    Liquid fuel/water injection system(optional)

    When a liquid fuel system is required, afactory-assembled demineralized waterinjection skid is furnished. This waterinjection skid is assembled on a bedplateand includes an AC motor-driven injectionpump with suction strainer, manifolds,control valves and instrumentation.

    When liquid fuel and water injection sys-tems are required, an additional skid for theprimary fuel and water scheduling compo-nents is provided and is located inside theturbine enclosure. In a typical liquid fuelinstallation, this skid contains liquid fuelflow dividers, liquid fuel control valves,water injection valves and a local instru-ment panel.

    Air inlet and exhaust gas systems

    Air that is drawn into the gas turbine is fil-tered via a two-stage pad filter. A self-clean-ing pulse filter is also an available option.After passing through the filter, the inlet airduct guides the air into the compressorinlet manifold. This manifold is designed toprovide a smooth flow pattern into the axialflow compressor. An inlet silencer providessound attenuation. After passing throughthe combustor and turbine section, com-bustion gas discharges axially through atransition section and into an exhaust stackfor simple cycle applications.

    In combined cycle applications, the exhausttransitions direct the exhaust gases into theHRSG before exiting the stack.

    Compressor water wash package

    The compressor water wash package is provided for both on-line and off-line com-pressor cleaning. This package incorporatesan AC motor-driven pump, an eductor fordetergent injection, piping, valves, orifices,interconnecting piping and a detergentstorage tank assembled on a bedplate.

    Piping packages

    SGT6-PAC 5000F plant piping is designedand manufactured to minimize field work.Each of the major pipe modules is factoryassembled to reduce field connections.

    The turbine pipe package is located adja-cent to the gas turbine and in the gas tur-bine enclosure. It contains valves and pip-ing assemblies for the turbine cooling airsystem and the lube oil system. The rotorcooling bleed valve is also located withinthe turbine piping package.

    Auxiliary packages

    17

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 18

  • Cooling systems

    Lube oil cooler

    An air-to-oil fin-fan lube oil cooler (water-to-oil cooler, optional) and the associated temperature control valve aremounted on top of the lube oil packageroof. The temperature control valve maintains the lube oil temperature withinthe design range by controlling the flow of oil through the cooler.

    Rotor air cooler

    Rotor cooling air is extracted from thecombustor shell, cooled by an externalcooler, and introduced into the turbinesection to be used for sealing purposesand to cool the appropriate rotating discs and rotating blades.

    The rotor air cooler system supplied for simple cycle applications is an air-to-air fin-fan heat exchanger fitted with a vari-able speed motor-driven fan. The energyremoved from the cooling air is released to the surrounding air.

    For SCC6-PAC 5000F package or SCC6-5000F Turnkey combined cycle applications, the rotor air cooling systemmay include an air-to-water heat exchanger(kettle boiler) instead of a fin-fan cooler.With the kettle boiler, the energy removedfrom the cooling air is recovered and used to produce low-pressure steam. This steam is introduced into the steam circuit to improve the plant efficiency.

    Fire protection system

    The fire protection system gives a visual indi-cation of actuation at the local control panel.There are two independent systems:

    An automatically actuated dry chemicalsystem is provided for the exhaust bearing area of the turbine. The system consists of temperature sensing devices,spray nozzles, a dry chemical tank, inter-connecting piping and wiring.

    The FM-200 fire suppressant system isprovided for total flooding protection of theturbine enclosure and the electrical controlpackage in accordance with the U.S.National Fire Protection Agency standards.

    The CO2-based fire suppressant system isalso available as an option.

    VT and surge cubicle

    A Voltage Transformer (VT) and surge cubicleis provided as a separate unit for connectionto an isolated phase bus. It contains twothree-phase sets of voltage transformers and one set of surge arresters.

    Auxiliary transformers (optional)

    The optional auxiliary power transformermay be included as part of the SGT6-PAC5000F bill of material.

    Isolated phase bus (optional)

    The optional isolated phase bus, located atthe starting package end of the gas turbineunit, carries power from the generator termi-nals to the customer connection. The VT andsurge cubicle connects to the bus assembly.

    Auxiliary packages

    18

    Electrical package

    VT & surge cubicle

    Inlet air system

    Generator enclosure

    Excitation package

    Starting package

    Rotor air cooler

    Lube oil cooler& lube oil package

    Water injection skid

    Fuel oil skid

    Hydraulic oil skid

    Gas turbineenclosure

    Exhaust transition

    Exhaust stack

    Figure 6 - SGT6-PAC 5000F arrangement diagram

    Figure 6 - SGT6-PAC 5000F simple cycle arrangement diagram depicts the location of themajor components described above.

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 19

  • Figure 7 - SGT6-PAC 5000F simple cycle plant general arrangement drawing

    25

    SGT6-PAC 5000F plant arrangement diagram

    19

    Key:

    1. Gas turbine (GT)2. GT enclosure3. Generator (OAC)4. Generator air inlet filter5. Turbine air inlet duct and silencer6. Turbine air inlet filter7. Fuel gas main filter/separator8. FM-200 fire protection9. Exhaust transition10. Exhaust stack

    11. Rotor air cooler (fin-fan)12. Dry chemical cabinet13. Water injection pump skid14. Fuel oil pump skid15. Hydraulic supply skid16. Lube oil package17. Lube oil cooler (fin-fan)18. Electrical package19. Compressor wash skid20. Starting package

    21. Brushless excitation22. VT & surge cubicle23. Isolated phase bus duct (by others)

    Comment: Items 13 and 14 only requiredwith Dual Fuel.Notes: The equipment shown is representa-tive information. This design is subject tochange at the discretion of Siemens. Alldimensions shown are in feet and inches(metric).

    87

    '-3"

    (26

    .59

    m)

    167'-4"(51 m)

    36

    '-1"

    (11

    m)

    16

    171812

    5

    6

    47

    1

    1315

    9

    10

    11

    8

    23

    19

    14

    21

    20

    2223

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 20

  • SGT6-PAC 5000F simple cycle performance

    20

    Following is the net reference performance for the SGT6-PAC 5000F power plant.

    Conditions: Natural gas or liquid fuel meeting Siemens fuel specifications. Elevation: sea level; 14.696 psia barometric pressure, 60%

    relative humidity, 59 F (15 C) inlet air temperature, 3.4 in. water (87 mm water) inlet loss, 5 in. water (127 mm water) exhaust loss,

    air-cooled generator and .90 power factor (pf).

    Combustor DLN Conventional Conventional DLN*type Dry Water injection Steam injection Steam augmentation

    Fuel Natural gas Natural gas Natural gas Natural gas

    Net power output (kW) 196,000 207,790 215,650 219,400

    Net heat rate (Btu/kWh) (LHV) 9,059 9,442 8,736 8,846

    Net heat rate (kJ/kWh) (LHV) 9,557 9,961 9,217 9,333

    Exhaust temperature (F/ C) 1,079/582 1,052/567 1,072/578 1,092/589

    Exhaust flow (lb/hr) 3,988,800 4,105,581 4,123,828 4,120,363

    Exhaust flow (kg/hr) 1,809,308 1,862,279 1,870,556 1,868,984

    Fuel flow (lb/hr) 82,542 91,205 87,579 90,272

    Fuel flow (kg/hr) 37,441 41,370 39,726 40,947

    Fuel Liquid Liquid Liquid Liquid**

    Net power output (kW) 186,650 193,417 206,244

    Net heat rate (Btu/kWh) (LHV) 9,451 9,674 8,879

    Net heat rate (kJ/kWh) (LHV ) 9,972 10,206 9,368

    Exhaust temperature (F/ C) 1,048/584 1,033/556 1,054/568

    Exhaust flow (lb/hr) 4,030,920 4,100,167 4,143,902

    Exhaust flow (kg/hr) 1,828,413 1,859,824 1,879,662

    Fuel flow (lb/hr) 95,361 101,146 98,999

    Fuel flow (kg/hr) 43,255 45,879 44,906

    * Steam injected through the combustor section casing into the compressor discharge air to increase output.

    ** Steam augmentation with liquid fuel available on a case-by-case basis.

    Correction curves

    To estimate thermal performance of the SGT6-PAC 5000F plant at conditions other than those noted above, the following correction

    curves are provided:

    Correction for compressor inlet temperature (Figure 8)

    Correction for excess exhaust pressure loss (Figure 9)

    Correction for excess inlet pressure loss (Figure 10)

    Correction for barometric pressure* (Figure 11)*Barometric pressure (BP) can be calculated from the site elevation (ELE) using: BP = 7.08601 E -09 x ELE2 -5.29221 E -04 x ELE +14.696

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 21

  • SGT6-PAC 5000F simple cycle performance

    21

    Correction curves

    To estimate thermal performance of the SGT6-PAC 5000F at conditions other than those noted, the following correction curves may be used:

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 22

  • SGT6-PAC 5000F technical data

    SGT6-PAC 5000FPlant weights and dimensions Shown below is a typical list of the major pieces of equipment along with their approximate shipping weights and nominal dimensions.

    Item Weight Length Width Height RemarksGas turbine 462,000 lbs 33 ft 0 in 13 ft 0 in 15 ft 0 inElectric motor starting package 36,500 lbs 22 ft 6 in 11 ft 6 in 16 ft 9 inElectrical package 33,000 lbs 32 ft 0 in 12 ft 6 in 11 ft 3 inLube oil package 60,000 lbs 25 ft 0 in 12 ft 0 in 12 ft 0 inLube oil cooler (fin-fan) 29,000 lbs 25 ft 0 in 12 ft 0 in 13 ft 8 in with support structureLube oil cooler (duplex plate) 16,000 lbs 13 ft 6 in 11 ft 10 in 7 ft 1 in with support structureTurbine piping package 35,000 lbs 40 ft 0 in 10 ft 10 in 11 ft 11 inRotor air cooler (fin-fan) 27,000 lbs 22 ft 0 in 13 ft 6 in 12 ft 0 inGenerator Aeropac ll 530,000 lbs 41 ft 0 in 13 ft 0 in 14 ft 0 in acoustic / weather enclosure; ships separately

    Heaviest piece lifted WeightDuring construction Air-cooled generator 550,000 lbsAfter construction Bladed gas turbine rotor 110,000 lbs

    22

    SGT6-5000F gas turbineCompressor

    Type Axial flowNumber of stages 16Rotor speed 3600 rpmPressure ratio 17:1Inlet guide vanes Variable

    Combustion system

    Combustors:Type Dry Low NOxConfiguration Can-annularFuel Gas fuel only

    Gas fuel & liquid fuel (option)Number 16

    Fuels: Natural gas pressure range 475 to 500 psig -

    Nominal @ gas turbine filter/separator inlet flange

    Liquid fuel (option) 50 to 90 psig @ fuel oil skid interface flange (Demineralized water injection required)

    Turbine

    Number of stages 4Number of cooled stages 3

    Bearings

    Journal bearing:Type Tilting padQuantity 2

    Thrust bearing: Drive endType Tilting padNumber 1

    Drive Cold end, direct coupled

    GeneratorStandard ANSI/IECType

    - Base Open air-cooled (OAC)- Option Totally enclosed water-to-air-cooled- Option Hydrogen-cooled

    Excitation- Base Brushless- Option Static

    Nameplate ratingMVA 249 MVAPower factor 0.90Voltage 15 KVCurrent 8200 AFrequency 60 HzSpeed 3600 RPMField current 1544 AField voltage 270 VAmbient temperature 59F / 15CCold gas temperature 32CInsulation class Class FOperation class Class FShort circuit ratio 0.45Direct axis impedance Saturated

    Xd = 2.13 per unitX'd = 0.26 per unitX''d = 0.19 per unit

    Starting systemElectric motor started AC MotorStarting time to base load* 30 min (base)Turning gear DC Drive

    Recommended inspection intervalsInspection type - Gas fuel Hours StartsCombustor 8,333 450Hot gas path 25,000 900Major overhaul 50,000 1,800

    *A fast-start option is available to provide 150 MW in 10 minutes.

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 23

  • 25

    SCC6-5000F combined cycle plants

    23

    General description

    Combined cycle plants can be made upof various combinations of gas turbines,HRSGs and steam turbines. The scope of supply can be a SGT6-PAC 5000Fpackage, SCC6-PAC 5000F power island or SCC6-5000F turnkey plant.

    A typical 2x1 combined cycle powerplant consists of two SGT6-5000F gasturbines each with a dedicated HRSGthat supplies steam to a shared steamturbine. The gas turbines will primarilyburn natural gas with optional provisionsto burn liquid fuel as a backup. Each gasturbine will be coupled with a three-pressure reheat HRSG, which will gener-ate steam to operate the steam turbine.Generators attached to the two gas turbines and the steam turbine will supply electrical power to the grid.

    Major equipment

    A typical 2x1 turnkey combined cycleplant consists of the following majorequipment:

    Two SGT6-5000F gas turbines with air-cooled generators

    Two three-pressure level reheat HRSGswith stacks (fired as an option)

    One multi-cylinder reheat condensingsteam turbine with air-cooled generator

    One water-cooled condenser using aforced-draft cooling tower

    One integrated plant distribution control system

    Balance of plant (BOP) equipment consisting of pumps, transformers,power electrics, etc.

    HV switchyard.

    Major equipment descriptions

    Gas turbine

    The SGT6-5000F gas turbine as outlined inthe general description can be applied in acombined cycle application.

    Heat recovery steam generator

    The three-pressure, reheat HRSGs produce steam, which drives the steamturbine. The exhaust gas flows horizon-tally through the HRSGs releasing heatthrough the finned tubes to thewater/steam cycle.

    Depending on specific project require-ments, the HRSG can be either a drum-type or a once-through design.

    The sections of the drum-type HRSG con-tain economizer tube bundles, evaporatortube bundles with associated steamdrums, and a superheater tube bundle.Feedwater is pumped through the econo-mizer sections for optimized performance.

    The once-through, BENSON technologyHRSG has an advanced superheater outletdesign to enhance fast start capability,making the plant better suited for oper-ating regimes between intermediate and continuous duty. The feedwater ispassed through a condensate polishingsystem and pumped through the sections of the boiler.

    Either HRSG design can be supplied withprovisions for SCR and/or CO catalyst.

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 24

  • 25

    Steam turbine

    The steam generated in the HRSG is sup-plied to a two-cylinder, reheat, condensingsteam turbine with high efficiency blad-ing. Depending on the back pressure orthe amount of HRSG supplemental firing,the steam turbine is optimized as either asingle-flow axial exhaust condensing type,a dual-flow side or a down exhaust condensing type.

    The single-flow turbine consists of a single-flow HP turbine element and acombined IP/LP element. The dual-flowturbine consists of a combined HP/IP turbine element and a double flow LPturbine element.

    Main steam is supplied directly to the HPturbine inlet valves. Hot reheat and IPinduction steam enters through the IPturbine inlet valves. In the dual-flowsteam turbine, LP induction steam entersthe steam path through a port normallylocated in the crossover pipe. In the single-flow steam turbine, LP steam enters thesteam path through an induction portappropriately located in the turbineblade path. Upon exiting the LP turbine,steam exhausts into a water-cooled orair-cooled condenser.

    100% steam turbine bypass system

    The condenser is designed to accommo-date the exhaust from the steam turbineplus the miscellaneous drains from thesteam system. The condenser is alsodesigned to allow 100% steam bypass of the steam turbine.

    Condensate pumps

    Condensate is pumped from the con-denser hotwell by 2x50% condensatepumps (one full capacity pump for eachHRSG). The condensate then passesthrough the low temperature economiz-er section in the HRSG prior to enteringthe LP steam drum and boiler feedpumpsection. For redundancy, an optional3x50% arrangement is available.

    Boiler feedwater pump island

    A boiler feedwater pump island concept isemployed using 2x50% pumps (one fullcapacity pump for each HRSG) headeredtogether. These pumps supply feedwaterto the HP and LP boiler sections of theHRSGs. The pumps are electric motor-driven and are located adjacent to theHRSG nearest the steam turbine. Thepumps take suction from the condensatepump discharge after the low temperatureeconomizer raises the pressure to theappropriate level to supply the feedwaterto the boiler section(s).

    Cooling system

    A typical combined cycle plant incorpo-rates a water-cooled condenser using aforced-draft wet cooling tower. Additionalarrangements include a condenser withonce-through cooling, air-cooling or ahybrid cooling tower.

    SCC6-5000F combined cycle plants

    24

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 25

  • SCC6-5000F combined cycle plants

    25

    Control, protection and monitoring

    Control, protection and monitoring func-tions for the SGT6-5000F gas turbine-based power plant are performed by theSiemens Power Plant Automation (SPPATM)system known as the SPPA-3000. Thismicroprocessor-based distributed controlsystem located within the electrical pack-age has the flexibility to accommodate awide range of plant configurations andinterface options.

    Although the SGT6-PAC 5000F powerplant control system is provided speci-fically for the gas turbine-generator unitand its direct auxiliaries, it is expandableto accommodate additional control systemautomation processors and cabinets of thesame manufacturer on the network, in thecentral control room or other locations.

    Balance of Plant (BOP) functions mayinclude thermal equipment, circulatingwater loops, switchyard monitoring andSCADA interface for a complete combinedcycle plant.

    Supplemental HRSG firing (option)

    Supplemental HRSG firing (duct firing) is available as an option to increase theplant output by introducing additionalheat energy into the gas turbine exhauststream. By adding burners strategicallylocated in the HRSG, plant output can be increased by over 6% with moderateduct firing and over 20% with heavyduct firing.

    Site layout and arrangement of equipment

    Using a modular approach, the SiemensReference Power Plant (RPP) can readilybe configured to satisfy a number of siteor customer specific requirements.

    Figure 12 - SCC6-5000F 2x1 combinedcycle plant general arrangement drawing(as shown on page 26) illustrates thebase design configuration for a singlefuel (natural gas only), outdoor arrange-ment with a cooling tower.

    BOP equipment will be provided inaccordance with Siemens RPP designs asmodified to suit site-specific requirements.Pre-engineered options are available toaddress customer requirements.

    The overall site and building arrange-ments were developed to optimize spacerequirements while maintaining ampleaccess for operation and maintenanceactivities.

    The gas turbine-generators, steam turbine-generator, condenser and associatedauxiliaries are normally located outdoorsbut can also be placed in a building asan option. The HRSG and associated auxiliary equipment are located outdoors.

    Figure 13 - SCC6-5000F 1x1 combinedcycle plant general arrangement drawing(as shown on page 27) illustrates the basedesign configuration for a single fuel(natural gas only), outdoor arrangementwith a cooling tower.

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 26

  • Figure 12 - SCC6-5000F 2x1 combined cycle plant general arrangement drawing

    SCC6-5000F plant arrangement diagrams

    26

    Key:

    1. SGT6-5000F Gas Turbine (GT) enclosure2. GT generator (TEWAC below inlet filter)3. GT air inlet filter4. Fuel gas filter/separator5. Rotor air cooler (kettle boiler type)6. Heat Recovery Steam Generator (HRSG)7. Fuel gas preheater8. Power control center9. Generator breaker10. Auxiliary transformer11. GT generator transformer12. Boiler feedwater pumps

    13. Steam turbine14. Surface condenser15. ST generator (TEWAC)16. Vacuum pumps17. Main condensate pumps18. Gland steam skid19. Lube oil skid20. Isolated phase bus duct21. ST generator transformer22. Cooling water pipe23. Cooling tower24. Cooling tower pump

    25. Demineralized water storage tank26. Compressed air system27. Control room building28. Roads29. Generation building (option)30. Bridge crane (option with generation

    building)Notes: The equipment shown is representativeinformation. This design is subject to change atthe discretion of Siemens. All dimensions shownare in feet and inches (metric). Cooling towerlocation to be determined by prevailing winds.

    2230

    26

    24

    23

    26

    16

    1417 18

    12

    25

    5

    6

    47

    1301315

    6

    8

    5

    1

    47

    28

    2

    38

    9

    1020

    27

    28

    11

    11

    20

    82

    3

    1914

    29

    8821

    208

    28

    2224

    23

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 27

  • SCC6-5000F plant arrangement diagrams

    27

    Figure 13 - SCC6-5000F 1x1 combined cycle plant general arrangement drawing

    Key:

    1. SGT6-5000F Gas Turbine (GT) enclosure2. GT generator (TEWAC)3. GT air inlet filter4. Fuel gas filter/separator5. Rotor air cooler (kettle boiler type)6. Heat Recovery Steam Generator (HRSG)7. Fuel gas preheater8. Power control center9. Generator breaker10. Auxiliary transformer11. GT generator transformer12. Boiler feedwater pumps

    13. Steam turbine14. Surface condenser15. ST generator (TEWAC)16. Vacuum pumps17. Main condensate pumps18. Gland steam skid19. Lube oil skid20. Isolated phase bus duct21. ST generator transformer22. Cooling water pipe23. Cooling tower24. Cooling tower pump

    25. Demineralized water storage tank26. Compressed air system27. Control room building28. Roads29. Generation building (option)30. Bridge crane (option with generation

    building)Notes: The equipment shown is representativeinformation. This design is subject to change atthe discretion of Siemens. All dimensions shownare in feet and inches (metric). Cooling towerlocation to be determined by prevailing winds.

    25

    26

    28

    7

    6

    12

    4

    5

    22

    24

    17

    148

    23 29

    8

    8 27

    1816

    1315

    19

    20 21

    30

    1 2

    8

    20

    38

    9 10

    28

    11

    28

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 28

  • Combined cycle performance

    The performance of combined cycle powerplants varies with the site conditions, theequipment selected, and the thermal cycledesign. For the SGT6-5000F gas turbinebased combined cycle turnkey plant, thecomponents and the cycle have beenselected to provide increased performance.

    With a turnkey plant scope, we control thedesign and supply of critical components,thus providing the customer with a singlepoint of contact for performance relatedissues. Turnkey combined cycle perform-ance is shown in the table below.

    Figures 14 through 19 provide factors to estimate the performance for differentcompressor inlet air temperatures and baro-metric pressures. Figure 20 (as shown onpage 30) is a typical cycle diagram for 2x1combined cycle configuration.

    Options are available to increase the plantoutput on hot days. An inlet air evaporatorcooler and/or supplemental HRSG firingcan be added to increase the plant output.The combined cycle 2x1 base and outputperformance (as shown on page 30)shows the typical base plant and typicalperformance enhanced plant data (includ-ing evaporative cooler and supplementalfiring options).

    SCC6-5000F plant performance

    28

    Typical SCC6-5000F turnkey combined cycle plant performance

    Plant designation SCC6-5000F 2x1 turnkey SCC6-5000F 1x1 turnkey

    Cooling configuration Cooling tower Once through Air-cooled Cooling tower Once through Air-cooled

    Net power (MW) 593.0 594.8 587.6 294.9 295.9 292.2

    Net heat rate Btu/kWh (kJ/kWh) 5983/(6312) 5965/(6293) 6039/(6371) 6013/(6344) 5995/(6325) 6069/(6403)

    Steam turbine back pressure in. Hg 1.58 1.00 2.48 1.58 1.00 2.48

    Conditions: Elevation: sea level; compressor inlet temp.: 59F, inlet and exhaust losses and auxiliary loads includes for net power.

    Correction curves

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 29

  • 25

    SCC6-5000F plant performance

    29

    Correction curves

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 30

  • Fuel gas heater

    Two SGT6-5000F gas turbines

    SST-5000steam turbine

    CondenserRotor air heat exchanger(Kettle boiler)

    Two Heat RecoverySteam Generators (HRSGs)

    HP steam to steam turbine

    HRH steam to steam turbine

    CRH steam to HRSG

    LP induction steam to steam turbine

    HP IP LP LP

    SCC6-5000F plant performance

    30

    Figure 20 - Cycle diagram with drum-type boiler

    Combined cycle 2x1 base and output enhanced performance

    Operating conditions Base plant Plant with performance options

    Evaporator cooler No Yes

    Supplemental firing No Yes

    Ambient temperature (F/C) 59/15 105F

    Relative humidity (%) 60 35

    Barometric pressure (psia/bars) 14.69/1.033 14.69/1.033

    Fuel Natural gas Natural gas

    Fuel heating value (LHV) 21511 Btu/lb 20980 Btu/lb

    Fuel heating value (LHV) 50034 kJ/kg 48800 kJ/kg

    Fuel HHV/LHV ratio 1.1 1.1

    Generator power factor 0.9 0.9

    ST backpressure (in.-HgA/mbar) 1.5/50 3.19/108

    ST throttle pressure (psia/bars) 1817/125 2277/157

    ST throttle temperature (F/C) 1050/565 1050/565

    ST reheat pressure (psia/bars) 351/24 442/30

    ST reheat temperature (F/C) 1050/565 1050/565

    Gross plant output (MW) 598 (1) 592.9 (2)

    Net plant output (MW) 590 (1) 580.1 (2)

    Net plant heat rate (btu/kWh) 5960 (1) 6227 (2)

    Net plant efficiency (%) 57.2 (1) 54.8 (2)

    (1) based on once through cooling (2) based on cooling tower

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 31

  • The reliable SGT6-5000F gas turbinetechnology can be used in low-Btu fuel(syngas) applications, such as IntegratedGasification Combined Cycle (IGCC) andBitumen upgrader projects where syngasfuel is available.

    The SGT6-5000F gas turbine has beenanalyzed for operation in syngas applica-tions. Few changes are needed whencompared to a natural gas fueled gasturbine. The major change is to a dualfuel (syngas and natural gas) combus-tion system specifically designed forIGCC and other syngas applications.Other changes include the addition of a fuel mixing skid, local N2 storage forpurging the fuel system during start upand shut down, control system changes,and additional monitoring systems need-ed due to the high H2 and CO fuel.

    The modified combustion system wasdesigned to operate on either syngas ornatural gas or both. The syngas capabledesign is a diffusion combustor derivedfrom the proven DF42 combustion systemutilized on natural gas and distillate oil fueled SGT6-5000F engines and onsyngas/natural gas in two W501D5 gasturbines at the LGTI IGCC project from1987 to 1995. The fuel nozzle is designedto accommodate multi-fuel operation,diluent injection, fuel transfers and co-firing. The gas turbine combustor coverplates are modified for syngas operation.

    Syngas is the primary fuel for IGCC applications. Natural gas is used for startup and as a backup fuel. During the startup process at 30% load, the gas turbineis transitioned to syngas and taken tobase load. The principal components ofthe syngas system are located outsidethe turbine enclosure.

    After the syngas flows through the syngassaturator and heater in the BOP piping, itis blended with N2 (as a diluent) at theblending station and supplied to the inletof the syngas strainer. Exiting the syngasstrainer, the syngas is routed throughsimilar components as the natural gassystem including the overspeed trip,throttle, and isolation valves and into the syngas manifold.

    Based on the proven SCC6-5000F 2x1combined cycle plant, a nominal 600 MWIGCC power island design has beendeveloped (as shown in Figure 21). Thisincludes a steam bottoming cycle that isfully integrated with the gasificationisland and a larger steam turbine to maximize plant output.

    In addition to the power island Siemensequipment scope of supply may includemost of the major compression solutionsfor todays IGCC plants, including air separation units, main air compressorsand O2, N2 and CO2 compression solu-tions. Depending on the needs of theIGCC project, Siemens can participate in a broader role in the project up to and including supplying the total plantas a member of an EPC Consortium.

    The SPPA-T3000 control system normallysupplied with a SCC6-5000F 2x1 com-bined cycle plant can be expanded tocontrol the entire IGCC plant, includingthe gasification island(s), gas clean-upsystems and the air separation unit(s).

    Integrated gasification combined cycle plant application

    31

    Local N2 Storage

    Figure 21 - SGT6-PAC 5000F for syngas applications

    Syngas Mixing Skid

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:48 PM Page 32

  • siemens.com/energy

    Published by and copyright 2008:Siemens AGEnergy SectorFreyeslebenstrasse 191058 Erlangen, Germany

    Siemens Power Generation, Inc.4400 Alafaya TrailOrlando, FL 32826-2399, USA

    Order No. E50001-W210-A104-V2-4A00Printed in USA1360, 806 COLMAM WS 0708.5

    All rights reserved.Trademarks mentioned in this document are the property of Siemens AG, its affi liates, or their respective owners.

    Subject to change without prior notice.The information in this document contains general descriptions of the technical options available, which may not apply in all cases. The required technical options should therefore be specifi ed in the contract.

    4008_SGT6_5000 June 2008.qxd 8/22/08 3:47 PM Page 1