Srl Compressors

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Nuovo Pignone S.p.A.Via Felice Matteucci, 250127 Florence - ItalyTel. +39-055-423211Fax +39-055-4232800e-mail: info.geoil&[email protected]/geoilandgas

GE Power SystemsOil & Gas

GE Power SystemsOil & Gas

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Nuovo Pignone started productionof overhung-impeller centrifugalcompressors (SRL) in 1966. The firstunit with an integral gear wascompleted in 1979. With their simple, compact structureand excellent reliability, SRLcompressors are especially suited toa wide range of heavy dutyapplications with air, steam andother gases such as those employedin the Petrochemical Industry. The high efficiency, reliability andoperational flexibility of the SRL lineof compressors is the result of theadvanced centrifugal compressordesign achieved through: extensiveexperience with machines in serviceall over the world; continuousimprovement of the aerodynamicand mechanical design; use ofsophisticated computer designcodes; advanced manufacturingprocesses; and innovative R&Dprograms. Customers benefit fromNuovo Pignone’s advancedtechnology through improvement inplant productivity. The custom-built compressors in thisline are individually engineered tomeet each customer’s specificneeds using proven standardizedcomponents. SRL compressorscombine the advantages of custom-built machines (maximum efficiency,layout flexibility, materials selectionetc.) and standardization (proven,reliable components; availability ofspare parts).The SRL compressor series comesin a range of sizes. For each size thebaseplate, gearbox, stage volutes,cooler shells, oil and gas piping andauxiliaries are standardized.Machines can be produced to meetthe individual requirements of eachapplication through appropriateselection of key design factorsincluding:

- Number of stages

- Shaft rotational speed

- Diameter of impellers

- Height of impeller blades

- Exchange surface of coolers

Advantages of SRL Compressors- Simplicity of Installation

- Unit prepackaged and tested at factory- No special foundations required

- Superior Operation- High efficiency and reliability- High compression ratio- Wide range of flow rate- Optimum rotor balance for low vibration level

- Absence of Lube Oil in Process Gas- Advanced seal system options available

SRLSRL Centrifugal Compressors for Air and Process Gas

©2002 Nuovo Pignone S.p.A. all rights reserved(Any use or reproduction even if partial is prohibited without a specific written authorization)

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- Ease of Maintenance- Designed for maintainability- Accessibility of components

SRL design options

• Single or multi-shaft models

• Direct or gear (integral or separate) driven

• Fixed or variable speed drivers

(electric motor, steam or gas turbine, gas or diesel engine)

• Oil-free gas delivery system

• Automatic capacity control and safety system to reliably match any operating condition

• Auxiliary systems to meet international standards and customer specifications

Package conceptSRL compressors are usuallymounted on a single base togetherwith all auxiliaries (e.g. oil pumps, oilreservoir, control instruments) andare delivered fully assembled andtested. Outstanding reliability,ruggedness, low installation andoperating cost, plus ease ofmaintenance are the key features ofthese packages which are especiallydesigned for heavy-duty continuousservice.The packages are usually installedoutdoors and can be fully automatedfor remote control.

Compressor nomenclatureCasing sizes and number of impellersare indicated in the compressordesignation by the digits followingthe compressor model. For example,SRL 806 is the designation for a sixstage compressor, size 800. Theletter D before the compressordesignation indicates a double flowconfiguration. (DSRL)

SRL 1001 Propane compressor forQatar

SRLSRL Centrifugal Compressors for Air and Process Gas

- two cover flanges (suction and driver side). The seal area, is contained in the driver side cover and all the vent/supply channels to the seal are drilled in the cover. The shaft support is overhung and bolted to the driver side cover

- a diaphragm that shrouds the impeller

- a suction duct that guides flow to

the impeller’s leading edge- a discharge diffuser (vaneless or

vaned)- an aerodynamic internal volute.

Cast casingsCast casings are normally used forstandard air and steam machines, butmay also be adopted for low-pressureprocess gas applications. They consist

of the following main components:- a cast scroll- an end cover that can be bolted

either to a gearbox casing or to a shaft support

- a discharge diffuser (vaned or vaneless);- a suction duct- a diaphragm that shrouds the impeller.The scroll is generally fixed to the endflange with a simple split locking ringthat allows easy disassembly.

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CASINGSWelded casingsWelded casings consist of thefollowing parts:- a scroll with the delivery nozzle in

a tangential position- an end cover that can be bolted

either to a gearbox casing or to a shaft support (the end cover contains the seal area; all the vent/supply channels to the seal are drilled in the cover)

- a suction duct to guide the flow through the impeller’s leading edge

- a diaphragm that shrouds the impeller - a discharge diffuser (vaneless or

vaned).The scroll is generally fixed to the endcover with a simple split locking ringthat allows easy disassembly.

Forged casingsForged casings are used for smalldiameter impellers and for high designpressures, and consist primarily of twopieces:- a scroll (produced from a single forging);- a diaphragm (with the dual

function of suction duct and discharge diffuser).

The scroll can be bolted either to agearbox casing or to a shaft support.It contains the seal area; all the vent/supplychannels to the seal are drilled in thecasing.The diaphragm shrouds the impellerand the discharge diffuser (vaned orvaneless type) is machined into it. Thediaphragm is fixed to the scroll bymeans of bolts or for very highpressures with shear rings.

Fabricated casingsFabricated casings are selected forlarge single impeller, directly drivencompressors, and consist of thefollowing parts:- one external housing (with the

delivery nozzle welded in a tangential position)

1 - Welded casing2 - Forged casings3 - Fabricated casing with internals

during assembly4 - Cast casings

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CCompressor Components

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INLET GUIDE VANESThe Inlet Guide Vane (IGV) systemallows wide capacity control of thecompressor with reduced energylosses.IGVs consist of a row ofaerodynamically shaped blades

1 - Vaned diffuser2 - Fully open inlet guide vanes3 - Rotor assembly during balancing

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IMPELLERSAll impellers used in Nuovo Pignonecentrifugal compressors come from anumber of standard families. Eachfamily contains a set of geometricallysimilar impellers with different flowcoefficients to match flowrequirements. All geometries havebeen tested in the company’s R & Dlaboratory.The following types of impellers areused on SRL compressors:- semi-open, 3D impellers for

high Mach number applications and/or when high tip speeds are needed (mainly air and steam applications);

- closed 3D impellers for lower-head, high flow applications;

- closed 2D impellers for small flow stages (ie, small process compressors or last stages of high discharge pressure machines).

Semi-open type impellers aremachined from heat-treated, solidforgings so that both the hub andblades are of uniform strength. Closedimpellers are welded to the shroud.Cast impellers may be used forspecial applications.The blades are generally backsweptto different angles in accordance withthe required performance.Each impeller is dynamically balancedand overspeed tested beforeassembly; the shafts are thendynamically re-balanced at low speedwith the impeller mounted.Nuovo Pignone has acquired vastexperience in manufacturing openand closed impellers with a largevariety of materials such as carbonsteel or stainless steels (ASTM A 705gr. 630, X12 Cr 13), materials toNACE requirements or specialmaterials (Titanium, INCONEL 718 orINCONEL 625).

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CCompressor Componentsplaced at the inlet of the stage. The blades can rotate around theiraerodynamic center in order to givethe suction flow a pre-swirl thatguarantees an optimum incidenceangle with the impeller’s leading edgeeven at reduced flows, minimizinginlet losses.

THE DISCHARGE DIFFUSERThe discharge diffuser can be eithervaneless or vaned (DGV).Vaned diffusers are used for highMach number machines to reducethermodynamic losses in the very highspeed impeller exit flow.

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- Gear meshing : The gear unit can berated in accordance with AGMA or with API Codes. The toothed portion of pinions is integrally forged with the shaft. The bull gear is shrunk on the low speed shaft.

- Shafts : The shafts are sized to transmit the gear rated power within the stress limits of AGMA Codes. They are made of one-piece, heat treated forged or hot-rolled alloy steel, and the entire length of the shaft is machined. Nuovo Pignone will take complete responsibility for the lateral and torsional analysis of the entire train.

- Radial bearings : The radial bearings are of the hydrodynamic fluid film, tilting-pad type for the high speed shaft and fixed profile type for the low speed shaft. The bearings are split for ease of assembly, equipped with anti-rotation pins and are firmly secured in the axial direction. The bearing design suppresses hydrodynamic instabilities and provides sufficient damping to limit rotor vibrations while the compressor is operating, loaded or unloaded, at the specified operating speed.

- Thrust bearings : The thrust bearings are designed for equal thrust capacity in both directions, and are sized for continuous operation under all specified conditions including all external forces transmitted by the couplings or by the gear mesh. The thrust bearings of high speed shafts can be the thrust collar type (standard for multi-stage compressors) or the tilting pad type for single impeller shafts with high axial thrust. Thrust bearings of low speed shafts are generally the hydrodynamic tapered land type (a tilting pad arrangement can be supplied on request).

SHAFTSUnless the compressor is integrallygeared, the shaft is machined from asingle forging of 40NiCrMo7 (AISI 4340). The impeller can beoverhung mounted at the end of theshaft by means of a frontal Hirthcoupling, by a flange (for high speedapplications), or hydraulically fittedwith a tapered coupling. Thrust collarscan be either replaceable ornon-replaceable.

SUPPORT CASINGThe support casing of the compressor(except for the Integrally Geared type)contains the compressor journal andthrust bearings. The journal bearingsare of the hydrodynamic fluid filmtype, tilting pad type for higherspeeds, or built to Customerspecifications. The bearings are split for ease ofassembly, equipped with anti-rotationpins and are firmly secured in theaxial direction. The bearing design suppresseshydrodynamic instabilities andprovides sufficient damping to limitrotor vibrations while the compressoris operating (either loaded orunloaded) at the specified operatingspeed. The thrust bearings are of thetilting pad type designed for equalthrust capacity in both directions andsized for continuous operation underall specified conditions including allforces transmitted by the coupling orby the impeller.

INTEGRAL GEARBOXThe integral gearbox consists of a bullgear and high speed pinions, with asingle-helical gear mesh.- Casing : The gearbox casing is

horizontally split. The lower part is fixed to the baseplate and the compressor stages are fixed to it.The gearbox casings can be either cast or fabricated.

1 - 3D Semi-open impeller2 - Support casing with shaft3 - Gearbox for a 6-stage electric motor

driven SRL 806 compressor4 - Gearbox for a 4-stage steam turbine

driven (direct input) DSRL 504compressor

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SHAFT ARRANGEMENTWith Integrally Geared compressors,many shaft arrangements are possiblein order to suit the required duty. Inparticular, the bull-gear can be drivendirectly by an electric motor (standard

- Dry gas seals : Used when treatedgases cannot be discharged, into the atmosphere.Seals can be supplied in several configurations:1. A tandem seal ring with

intermediate labyrinth.2. A tandem seal ring without

intermediate labyrinth.3. A double (face to face)

arrangement.4. A single ring arrangement.5. Single, tandem or double

arrangement with carbon ring third-stage seal (in order to limit nitrogen buffer gas consumption).

The face of the seal’s rotating ring is recessed over more than 50 percent of its surface by groovesfrom 7.5 to 10 micrometers in depth etched into the face material. They extend to the dam against which the process gas forms a seal.The grooves are the key to non-contact operation of the seal. They serve two vital functions: 1. Provide hydrostatic separation of the sealing faces (utilizing only the pressure of the process gas, without rotation of the seal). 2. Generate a pumping action due to viscous drag through the gas, thus creating hydrodynamicseparating forces between the faces, or lift-off.

- Oil mechanical seals: Supplied for special types of service in which polymerization of the gas is possibleand no clean buffer gas is available, or at the customer’s request. Seals are supplied in easily replaceable cartridges.

solution) or by a turbine (gas orsteam); the number of pinions canvary (depending on the size of thestage casings) from one to four.

SEALSThe following types of seals can beinstalled on SRL compressors:- Labyrinth seals : Commonly used

when non-toxic gases are handled orwhen operating pressures are low. The seal material can be either aluminium alloy or stainless steel.

Typical seal arrangement1 - Labyrinth seal2 - Tandem dry gas seal3 - Double dry gas seal4 - Mechanical oil seal

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LEGEND1 - Oil reservoir2 - Suction strainer3 - Oil pump4 - Relief valve5 - Oil cooler6 - Oil filter7 - Oil accumulator8 - Run-down tank

- Locally mountedinstrument

- Panel mountedinstrument

LG - Level glassLSL - Low level switchLAL - Low level alarmPI - Pressure indicatorPCV - Pressure control

valvePSL - Low pressure

switchPAL - Low pressure

alarm and stand-bypump start-up

PSLL - Minimum pressureswitch

PALL - Minimum pressureshut-down

PSH - High pressureswitch

PAH - High pressurealarm

PDISH - High diff. pressureindicator and switch

PDAH - High diff. pressurealarm

TI - Temperatureindicator

TSH - High temperatureTAH - High temperature

alarmTSHL - High/low

temperature switchFG - Flow glass

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Lube oil systemA force-fed lube oil system ensuresthat the journal and thrust bearings areproperly lubricated. The system canbe designed compliant with either API614 or API 672 and is suitable forcontinuous compressor operation. It generally consists of:

• oil reservoir

• steam turbine or electric motor driven pumps (the main pump can also be driven by the compressor/gearbox low speed shaft)

• full-flow oil coolers

• twin oil filter allowing cartridges to be changed during operation

• automatic by-pass valve to control oil pressure at the bearing manifold

• monitoring and safety instrumentation.The lube oil console can be either ona separate skid or integrated on themain baseplate with the machine.

Seal oil systemThe seal oil system supplies filtered oilto the mechanical seals at the correctpressure and temperature, and can beeither derived from the lube oil systemor completely separate. The system is designed in accordancewith API 614 and is suitable forcontinuous compressor operation.It generally consists of:

• oil reservoir

• electric motor driven pumps

• full-flow oil coolers

• twin filter allowing cartridges to be changed during operation

• Overhead tank with level or pressure control

• automatic seal oil traps

• monitoring and safety instrumentation.The seal oil console can be either on aseparate skid or integrated on the

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LEGEND1 - Oil reservoir2 - Oil pump3 - Relief valve4 - Oil cooler5 - Oil filter6 -Seal OiI Trap7 -Degassing tank



LG - Level glassLSL - Low level switchLAL - Low level alarmPI - Pressure indicatorPDCV - Diff. pressure control

valvePDISL- Diff. pressure indicator

and switchPDAL - Low diff. pressure

alarmPDALL - Low diff. pressure

shut-downPDISH - High diff. pressure

indicator and switchPDAH - High diff. pressure

alarmTI - Temperature

indicatorTSH - High temperature

switchTAH - High temperature

alarmTSHL - High/low

temperature switchFG - Flow glass

EH

TSHL

PIPI

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PDISL

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1 - Typical API 614 lube oil system diagram

2 - Typical API 672 lube oil system diagram

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3 - Typical seal oil diagram

AAuxiliaries

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Compressor control panelThe control panel implements thecompressor start/stop sequence logic,alarm annunciator sequence logic,capacity control logic etc. The PLC is programmed prior toshipment and includes a serialcommunication interface RS422 withModbus protocol for connection to asupervision and control system (i.e. DCS, PC, telemaintenance etc.).The control panel front includes avideo terminal connected to the PLC,which provides the following functionsorganized in pages:

• top level diagram

• unit controls to start / stop and control the compressor, auxiliary motors and heaters (with status display)

• process data monitoring (pressure, temperature, level)

• alarm display

• shutdown display

• surge controller monitoring

• hour meter

• event recorder.If field instrumentation includesanalogue signals from pressure and

temperature transmitters, the operatorinterface can perform additionalfunctions:

• operating parameter display

• PLC set point adjustment

• trend recording of process dataThe compressor vibration monitoringsystem is also located on the controlpanel.

LEGENDA - ImpellerB - Balancing lineC - Seal gasE - PurgeE1 - BufferE2 - PurgeF - Increasing speed gearL1 - Primary ventL2 - Secondary ventS - Frame



- Function on PLC anddisplay (I.O.P.)

FI - Flow indicatorFO - Flow orificePCV - Pressure control valvePDIC - Pressure differential

indicator controllerPDIT - Pressure differential

indicator transmitterPDI - Pressure differential

indicatorPIT - Pressure indicator

transmitterPI - Pressure indicator

SEAL GASFOR START UP

PI

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PI

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FO

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PITPAH

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PI

PITPAH

PAL I

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PDIPDAH

PI

PDI

PI

FI

PI

BUFFER/PURGE GAS

L3 TO SAFE AREA

L2

L3 TO FLARE

PIPITPAHH I

PDIPDITPDAH I

PDIT

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1 - Dry gas seal control panel for a 4 stage SRL 254 compressor

2 - Typical tandem dry gas seal system diagram

3 - Typical control panel

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Dry gas seal systemThe dry gas seal control systemsupplies filtered gas (either process orother clean gas) and nitrogen buffer gasto the dry gas seals at the correctpressure. The system is designed basedon Nuovo Pignone’s extensive experiencewith this type of sealing system.It generally consists of:

• twin filters allowing cartridges to be changed during operation

• control valves for adequate buffering of the seals

• monitoring and safety instrumentationThe seal gas system can be either ona separate console or integrated onthe main baseplate with the machine.

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AAuxiliaries

Flow Control:by adjustable guide vanesby suction throttlingby speed variationby discharge throttling

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OPERATION CONTROLThe following methods are available tocontrol flow and suction or dischargepressures under varying processconditions:

• compressor speed variation : this method is utilized when a compressoris driven by a variable speed driver

• discharge throttling : a valve is fitted in the discharge piping so thatpressure at the compressor outlet nozzle may increase while maintaining the normal value downstream of the valve

• suction throttling : a valve is fitted in the suction piping so that suction or discharge pressure can be regulated according to the process requirements

• adjustable inlet guide vanes : these vanes alter the gas flow direction as it enters the impeller, thus varying the pressure ratio and flow of the compressor. These guide vanes can be placed before each compression stage

ANTISURGE CONTROLShould a flow below the compressorsurge limit be required a by-pass mustbe used. Part of the compressed gasis recirculated to raise the compressorsuction flow above the surge limit.The system is standard for allcentrifugal compressors and comesinto operation as a relief mechanismor when other control system optionsare not capable of handling excessflow or pressure.When air or inert gas is beingcompressed it may be blown-off to the atmosphere instead of beingrecirculated.

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1 - Operation control2 - Indoor facilities for performance tests

or full-load tests with inert gas

GGeneralTEST FACILITIESCompressor components are subjectto a long series of tests in order toguarantee perfect matching to theirdesign specifications. Casings aresubmitted to hydraulic or pneumaticpressure testing, depending on thetype of service. Impellers are checkedwith ultrasonic and dye penetrantliquids. Facilities allow overspeedtesting of single impellers.All compressors are mechanicallytested before delivery. The test drivermay be an electric motor, a steamturbine (the test facility is equippedwith a complete plant for production ofsteam at 55 bar and 500°C) or a gasturbine.When Nuovo Pignone supplies acomplete compressor unit with motor,steam or gas turbine driver, a stringmechanical test can be carried out on the complete train.Performance testing with air or other gases in a closed loop can also be carried out. Nuovo Pignone has uprated and updated its test facilities with the construction of a new test room designed for maximumflexibility to adapt to various testconditions and requirements.

Full-load, full-pressure tests (includingflammable gases) to check rotorstability as well as performance ofmachines or complete systems canalso be carried out.A number of outdoor full load test rigsare available at the Florence and Massashops providing Nuovo PignoneCustomers with test facilities to meetvirtually any need.

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performance prediction in allapplications.Advanced knowledge of non-stationary flow phenomena and highspeed rotor dynamics has led to theunsurpassed reliability andavailability of these machines.

QUALITY ASSURANCEThe Nuovo Pignone QualityAssurance group is centered inFlorence and has a staff of over 60people stationed throughout theCompany’s plants. One of thefundamental duties of the group isthe development of quality standardsand assistance in the correctapplication of all quality assuranceprocesses in all productdevelopment, manufacturing, andtesting operations. Speciallaboratories certified by Sinal, areequipped for measuring mechanicalproperties, chemical and opticalemission spectrometric analyses,fatigue tests and macro andmicrographic examinations (scanningelectron microscopy). A calibrationroom certified by SIT for checking andcalibrating lengths, forces andtemperatures is also available.Nuovo Pignone’s Quality AssuranceSystem has been certified to meetISO 9001 standards for design,manufacture, installation and after-sales service of centrifugalcompressors, centrifugal pumps,reciprocating compressors, gas andsteam turbines, gas expanders, heatexchangers and pressure vessels byLloyd’s Register Quality AssuranceLtd., one of the most authoritativeinternational certificationorganizations.

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GGeneral

e Pride &The Commitment

RESEARCH AND DEVELOPMENTResearch and Development plays an important role in Nuovo Pignone’sstrategies and therefore receivessubstantial resources.One of the main objectives iscontinuous updating and improvementof existing products to extend the state-of-art in the traditional Oil & Gasapplications such as natural gas,fertilizers, methanol, refining and relatedchemical industries.New products are developed drivenby customer needs in applications

that fit within Nuovo Pignone’sbusiness strategy and expertise.Research on centrifugal compressorsaccounts for a substantial portion ofthe company’s total research activity.Nuovo Pignone’s test laboratory isequipped with a number of advancedtest facilities both for developing andtuning major compressor components(stages, seals, bearings) and forperforming all kinds of stress, vibrationand rotor dynamic investigations.Besides testing, continuous effort isdedicated to development andimprovement of analytical tools usedin the fluid dynamic, structural androtor dynamic design of componentsand complete compressors.Many years of analytical andexperimental research work oncomponents has led to establishing awide selection of standardized stages,each individually tested and tuned andapplication engineering tools thatprovide maximum reliability in

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1 - Modal analysis of centrifugalimpeller by holographic interferometry with a laser system

2 - ISO 9001 certification

ServiceS

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CUSTOMER SERVICENuovo Pignone provides the users ofits machines with prompt, efficient andtechnologically advancedmaintenance and repair service to guarantee high machine efficiency,continuity of operation and maximumsafety. This service includes:

• Technical support

• Periodic visits to plants

• Diagnostic analysis of installations

• Overhauls, repairs and conversions of installed machinery

• Customized original spare parts supplies

• Maintenance contracts

• Personalized training courses for customers’ personnel.

SERVICE ORGANIZATIONNuovo Pignone Global Services is anorganization dedicated to meetingcustomer service needs.It is fully integrated with the newproduct engineering andmanufacturing organizations toprovide state-of-the-art solutions to theinstalled fleet. Global Servicesoperates a Service Shop adjacent tothe main production plant in Florencefor the high tech overhaul andrefurbishment of machines andcomponents. A warehouse containingover 40,000 different parts ismaintained and a moderncomputerized parts managementsystem is in place to insure rapiddelivery of replacement parts on eithera scheduled or an emergency basis.

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1 - Computerized system for spare parts warehouse management

2/3 - Customer Training features shop visit

A global service network ensures rapidresponse to maintenance needsanywhere in the world.This organization consists of:

• Service centers in strategic locationsworldwide

• Traveling Service Teams which maintain contact with users through periodic visits to plants

• Authorized shops which carry out machine maintenance with Nuovo Pignone technology.

Service contractsHighly-skilled engineers, an extensivespare parts inventory and an efficientglobal service network allow NuovoPignone to offer its customers tailor-made service packages.

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GeneralAir compressors are used in airseparation, synthetic fibre and fertilizerplants as main process gascompressors, and in all industrial plantsas service air compressors.

Technical dataThe inlet flow for such machines canvary from 10,000 to 200,000 m3/h (6,000to 120,000 cfm), with a max. dischargepressure of up to 50 bar (730 psi).

Main characteristicsAir compressors are generally multi-shaft, integrally geared type, singleor multi-stage (up to 6 stages).Compressors are modularized in order to meet varying Customer needs.High compression efficiencies areacheived by using 3-D impellersspecially designed for this service.Inlet Guide Vanes are available for eachcompression stage, permitting extremelylarge compressor turndown with highefficiencies throughout the range. Sealsare generally labyrinth type (single, drygas type for last stages of high pressureapplications). Multi-stage compressorsare equipped with inter-coolers with anintegral condensed water separator.

DriversDrivers for this type of compressor aregenerally electric motors, but it is alsopossible to use steam and gas turbines(either as a direct driver or through anintermediate gearbox).

Package arrangementIn multi-stage compressors, coolers arelocated below the compressor togetherwith the lube oil system in order toprovide a very compact arrangement ofthe unit. Lube oil systems can be eitherseparate or integrated on the maincompressor baseplate.

Applicable codes and standardsCompressors may be designed eitheraccording to API 617 or API 672, orcustomized to Customer’s specificrequirements.

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AAir Compressors

3

SRL 450

SRL 600

SRL 800

SRL 900

SRL 1000

6 STAGES

5 STAGES

4 STAGES

3 STAGES

2 STAGES

1 STAGE

100

50

40

30

20

1098765

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110 20 30 40 50 60 70 80 90 100 200.000

SUCTION VOLUME FLOW (m 3/h)

DIS

CH

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GE

PR

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SU

RE

(B

AR

)

1 - Performance range2 - SRL 453 service air compressor installed in an Alfa Romeo

workshop in Milan - Italy (17000 Nm3/h from 1 to 8 bar-abs)

3 - SRL 806-Air compressor for GE’s test bed in Schenectady, NY - USA (4900Nm3/h;

Suct. press. 1 bar-abs; Disch. press. 27.8 bar-abs; Inst. power 7550 kW)

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GeneralThis type of compressor is mainlyused as a booster in petrochemicalapplications, or as a recyclecompressor in polyethylene andpolypropylene plants.Axial inlet flow guarantees an optimumaerodynamic design, and thereforevery high efficiency. Due to theirrugged mechanical design, this typeof machine delivers very highreliability.Almost all gases can be handled bythis type of compressor withappropriate construction materials andseal systems.

Technical dataFlows can vary from 5,000 to 120,000m

3/h (3,000 to 70,000 cfm), with

discharge pressure up to 50 bar (730 psi).

Main characteristicsSeveral configurations are available to cover all applications of this type of machine.Impellers are 3-D, backswept, semi-open or closed type, overhungmounted on the shaft. The thrustbearing is located between the twojournal bearings and is of the tilting-pad type.A special design, with internal spiralvolutes (to avoid any dead-point in theflow), is available for process gas thatmay polymerize during operation (forexample in PP and PE plants).Inlet Guide Vanes are available forfixed-speed units to increase theoperating range of the compressorwhile maintaining high efficiency.Seals can be dry gas, mechanical oilor labyrinth type, depending on theservice requirements.

DriversThis type of unit can be driven eitherby an electric motor (directly coupledor via an external gearbox to increase

speed), or by a steam or a gas turbine(directly coupled or via an externalgearbox to increase or decreasespeed).

Package arrangementThe baseplate generally accommodatesboth the compressor and its driver.The lube oil system can be eitherintegrated with the main machinebaseplate or provided as a separateconsole.

Applicable codes and standardsGenerally designed according to API 617, or customized to Customer’sspecific needs.

1 - SRL 801 for a polyethylene plant (during assembly)(871,000 Nm3/h from 25 to 26.3 bar-abs2,300 kW installed power)

2 - SRL 1001 propane booster compressor (594,000 Nm3/h from 12.3 to 15.6 bar-abs4,800 kW installed power)

3 - SRL 451 propane compressor directly driven by an NG 32/25 steam turbine(168,000 Nm3/h from 33 to 47.5 bar-abs1,800 kW installed power)

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PProcess Gas Compressors (Single Stage - Directly Driven)

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flow guarantees an optimumaerodynamic design, and thereforevery high stage efficiency. Due to its rugged mechanical design,this types of machine delivers veryhigh reliability.Almost all types of gases can behandled by this compressor designwith appropriate construction materialsand seal systems.

Technical dataFlows can vary from 500 to 50,000m3/h (300 to 30,000 cfm), withdischarge pressure up to 100 bar(1,500 psi).

Main characteristicsSeveral configurations are available to cover all applications of this type of machine.Impellers are 3-D or 2-D, backsweptsemi-open or closed type, overhungmounted on the shaft. The thrustbearing is located on the pinion shaftand is of the thrust collar type. Thejournal bearings of the pinions are thetilting-pad type.Inlet Guide Vanes are available toincrease the operating range of thecompressor with low impact onefficiency.Seals can be of the dry gas, mechanicaloil or labyrinth type, depending on theservice requirements.

DriversThis type of unit can be driven directlyeither by an electric motor, or by asteam or a gas turbine.

Package arrangementThe baseplate generallyaccommodates both the compressorand its driver. The lube oil system canbe either integrated with the mainmachine baseplate or provided as aseparate console.

Applicable codes and standardsGenerally designed according to API617 or customized to Customer’sspecific requirements.

GeneralThis type of compressor is used inseveral petrochemical processes,either for low-flow/high pressureapplications, or for high-flow/lowpressure applications.The integrally geared compressorfeatures a bull gear and from one to

four high speed pinions. One or twoimpellers can be mounted on eachpinion shaft. The multi-shaftconfiguration allows frequentintercooling, and therefore bettercompression efficiency compared to traditional in-linecentrifugal compressors. Axial inlet

1 - SRL 251 natural gas recycle compressors(2,200 Nm3/h from 1 to 1.5 bar-abs70 kW installed power)

2 - SRL 253 dichloromethane compressor all in AISI316stainless steel materials,(500 Nm3/h from 1 to 5 bar-abs455 kW installed power)

3 - SRL 254 natural gas booster compressor (70,700 Nm3/h from 33 to 68 bar-abs2,500 kW installed power)

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GeneralRising energy costs have led to ademand for high efficiency machinesfor energy recovery.Steam compressors are employed invarious sectors, such as the agriculture-food Industry, chemical industry, paperindustry and desalination plants.Another application of SRLcompressors is in Geothermal powerstations to extract non-condensablegases from the steam turbinecondensator.

Technical dataFlows can vary from 5,000 to 250,000m3/h (3,000 to 150,000 cfm) perimpeller, with discharge pressure up to10 bar (150 psi).

Main characteristicsSteam compressors are of the integrallygeared type, single or multi-stage (up to6 stages) machines.The compressors are modularized, for flexibity in meeting Customerrequirements.High pressure ratios together with highcompression efficiencies are reachedby using 3-D open impellers speciallydesigned for this service.Inlet Guide Vanes are available for eachcompression stage to provide a largeturndown for the compressor with highefficiencies throughtout the range.Labyrinth type seals are always used.

DriversDrivers for this type of compressor canbe either electric motors or steamturbines (as a direct driver).

Package arrangementThe baseplate generally accommodatesboth the compressor and its driver. Thelube oil system can be either integratedwith the main machine baseplate orprovided as a separate console.

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SRL COMPRESSOR

1 - SRL 903 for geothermal application (4,200 Nm3/h from 0.1 to 1.2 bar-abs550 kW power)Directly driven by a steam turbine

2 - SRL 1001 steam compressor for a food industry(101,000 Nm3/h from 0.8 to 1.6 bar-abs3,850 kW installed power)

3 - Typical process diagram for a food industry application

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SSteam Compressors

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1. SRL 601Polypropylene recycle compressorinstalled in Tarragona, Spain- Flow 229,000 Nm3/h - Suct. Press. 14.5 bar-abs- Disch. Press. 15.6 bar-abs- Inst. Power 850 kW

2. SRL 603Air+carbon monoxide compressorinstalled in Geel, Belgium- Flow 265,00 Nm3/h - Suct. Press. 1 bar-abs- Disch. Press. 5.3 bar-abs- Inst. Power 2,600 kW

3. SRL 454Air compressor for a Caprolactam plant in Shijiazhuang, ChinaThe compressor is driven by a steam turbine through an external gearbox- Flow 17,000 Nm3/h - Suct. Press. 1 bar-abs- Disch. Press. 13 bar-abs- Inst. Power 2,350 kW

4. SRL 454Psa tail gas compressor installed in Tula, Mexico- Flow 21,300 Nm3/h - Suct. Press. 1.1 bar-abs- Disch. Press. 9 bar-abs- Inst. Power 2,800 kW

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5. SRL 603 and SRL 453Compressor for an air fractionating plant in Middle East- Flow 27,000/18,000 Nm3/h - Suct. Press. 0.8/0.8 bar-abs- Disch. Press. 7.5/9 bar-abs- Inst. Power 2,800/2,060 kW

6. SRL 601Recycle gas compressor for an EO/EG plant in Pralca, VenezuelaSingle stage compressor, electric motor, driven through an external gearbox speed increaser- Flow 238,000 Nm3/h - Suct. Press. 19 bar-abs- Disch. Press. 23 bar-abs- Inst. Power 1,750 kW

7. SRL 801Nitric acid compressor installed in Ambes, FranceThe compressor is driven by a steam turbine through an expander - Flow 168,000 Nm3/h - Suct. Press. 4.6 bar-abs- Disch. Press. 11.5 bar-abs- Inst. Power 7,250 kW

8. SRL 903For geothermal applicationinstalled in Le Prata, Italy- Flow 4,200 Nm3/h - Suct. Press. 0.1 bar-abs- Disch. Press. 1 bar-abs- Inst. Power 550 kW

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Srl Compressors

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