PositiveDisplacementPumps—Rotary

APISTANDARD676

FOURTHEDITION,FEBRUARY2022

AP

AmaricanPetroleumlnstitute

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CopynghtAmenicanPetroleumIrattute

SpecialNotes

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Copyright◎2022AmericanPetroleumInstitute

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Foreword

NothingcontainedinanyAPlpublicationistobeconstruedasgrantinganyright,byimplicationorotherwise,forthemanufacture,sale,oruseofanymethod,apparatus,orproductcoveredbyletterspatent.Neithershouldanythingcontainedinthepublicationbeconstruedasinsuringanyoneagainstliabilityforinfringementofletterspatent.

Theverbalformsusedtoexpresstheprovisionsinthisdocumentareasfollows.

Shall:Asusedinastandard,"shall"denotesaminimumrequirementtoconformtothestandard.

Should:Asusedinastandard,"should"denotesarecommendationorthatwhichisadvisedbutnotrequiredtoconformtothestandard.

May:Asusedinastandard,"may"denotesacourseofactionpermissiblewithinthelimitsofastandard

Can:Asusedinastandard,"can"denotesastatementofpossibilityorcapability.

ThisdocumentwasproducedunderAPlstandardizationproceduresthatensureappropriatenotificationandparticipationinthedevelopmentalprocessandisdesignatedasanAPIstandard.QuestionsconcerningtheinterpretationofthecontentofthispublicationorcommentsandquestionsconcerningtheproceduresunderwhichthispublicationwasdevelopedshouldbedirectedinwritingtotheDirectorofStandards,AmericanPetroleumInstitute,200MassachusettsAvenue,NW,Suite1100,Washington,DC20001.Requestsforpermissiontoreproduceortranslatealloranypartofthematerialpublishedhereinshouldalsobeaddressedtothedirector.

Generally,APIstandardsarereviewedandrevised,reaffirmed,orwithdrawnatleasteveryfiveyears.Aone-timeextensionofuptotwoyearsmaybeaddedtothisreviewcycle.StatusofthepublicationcanbeascertainedfromtheAPIStandardsDepartment,telephone(202)682-8000.AcatalogofAPlpublicationsandmaterialsispublishedannuallybyAPI,200MassachusettsAvenue,NW,Suite1100,Washington,DC20001.

SuggestedrevisionsareinvitedandshouldbesubmittedtotheStandardsDepartment,API,200MassachusettsAvenue,NW,Suite1100,Washington,DC20001,standards@.

iii

Contents

Page

1Scope 1

2NormativeReferences 1

3TermsandDefinitions 4

4General 10

4.1UnitResponsibility 10

4.3PumpDesignations 10

5.1[]UnitsofMeasure 16

5.2StatutoryRequirements 16

5.3DocumentationRequirements 16

6BasicDesign 16

6.1Genera 16

6.2SelectionandRatingofPumpType 19

6.3Pressure-containingandPressure-retainingParts 19

6.4CasingConnections 20

6.5AuxiliaryConnections 21

6.6Flanges 2

6.7ExternalForcesandMoments 23

6.8RotatingElements 25

6.9MechanicalShaftSeals 26

6.10BearingsandBearingHousings 27

6.11VibrationLimits 28

6.12Lubrication 29

6.13Materials 30

6.14NameplatesandRotationArrowS 36

7.Accessories 36

7.1Drivers 36

7.2CouplingsandGuards 38

7.3BeltDrives 40

7.4Baseplates 41

7.5Pressure-limitingValves(PLVs) 43

7.6ControlsandInstrumentation 44

7.7AuxiliaryPiping 4

7.8PulsationandVibrationControlRequirementsforMultiphaseSkids 4

7.9SpecialTools 4

8Inspection,Testing,andPreparationforShipment 45

8.1Genera 45

8.2Inspection 45

8.3Testing 47

8.4PreparationforShipmen 51

9Vendor'sData 52

9.1Genera 52

AnnexA(informative)RotaryPumpDatasheets 53

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Contents

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Page

AnnexB(informative)FactorsAffectingTwinScrewPumpWearRateandVolumetricEficiency 64

AnnexC(informative)Inspector'sChecklist 69

AnnexD(informative)ContractDocumentsandEngineeringDesignData 71

AnnexE(informative)RotaryPumpVendorDrawingandDataRequirements(VDDRs) 76

AnnexF(informative)NetPositiveSuctionHead(NPSH)vsNetPositiveInletPressure(NPIP) 88

AnnexG(informative)TypicalP&DforMPPPumps 90

Bibliography 91

Figures

1SlidingVanePump(VaneinRotor) 11

2SingleLobePump 11

3ThreeLobePump 12

4ExternalGearPump 12

5InternalGearPump 12

6Progressing/ProgressiveCavityPump(PCP) 13

7TwinScrewPump(withTimedGears) 13

8Three-screwPump(withUntimedGears) 13

9RotaryPumpConsolidatedRangeChart(TypicalRangeinSIUnits) 14

10RotaryPumpConsolidatedRangeChart(TypicalRangeinUSCUnits) 15

Tables

1PumpClassificationTypeIdentification 10

2NozzleLoadings 23

46

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nd rds…………………………34

5TestTolerances 50

C.1Inspector'sChecklist 69

vi

Introduction

Thisstandardisbasedontheaccumulatedknowledgeandexperienceofmanufacturersandusersofrotarypositivedisplacementpumps.Theobjectiveofthisstandardistoprovideapurchasespecificationtofacilitatetheprocurementandmanufacturerofrotarypositivedisplacementpumpsforuseinpetroleum,chemical,andgasindustryservices.

Theprimarypurposeofthisstandardistoestablishminimumrequirements.Thislimitationinscopeisoneofcharterasopposedtointerestandconcem.

Energyconservationisofconcernandhasbecomeincreasinglyimportantinallaspectsofequipmentdesign,application,andoperation.Thusinnovative,energy-conservingapproachesshouldbeaggressivelypursuedbythemanufacturerandtheuserduringthesesteps.Alternativeapproachesthatmayresultinimprovingenergyutilizationshouldbethoroughlyinvestigatedandbroughtforth.Thisisespeciallytrueofnewequipmentproposals,sincetheevaluationofpurchaseoptionswillbebasedincreasinglyontotallifecostsasopposedtoacquisitioncostalone.Equipmentmanufacturers,inparticular,areencouragedtosuggestalternativestothosespecifiedwhensuchapproachesachieveimprovedenergyeffectivenessandreducedtotallifecostswithoutsacrificeofsafetyorreliability.

Thisstandardrequiresthepurchasertospecifycertaindetailsandfeatures.Althoughitisrecognizedthatthepurchasermaydesiretomodify,delete,oramplifysectionsofthisstandard,itisstronglyrecommendedthatsuchmodifications,deletions,andamplificationsbemadebysupplementingthisstandard,ratherthanbyrewritingorincorporatingsectionsthereofintoanotherstandard.

APIstandardsarepublishedasanaidtoprocurementofstandardizedequipmentandmaterials.Thesestandardsarenotintendedtoinhibitpurchasersorproducersfrompurchasingorproducingproductsmadetootherstandards.

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PositiveDisplacementPumps—Rotary

1Scope

Thisstandardcoverstheminimumrequirementsforrotarypositivedisplacementprocesspumpsandpumpunitsforuseinthepetroleum,petrochemical,andgasindustryservices.Controlled-volumepumps,hydraulicallydrivenpumpsandpositivedisplacementreciprocatingpumpsarenotincluded(seeAPI674forpositivedisplacementreciprocatingpumpsandAPI675forcontrolled-volumepumps).

Forrotarypositivedisplacementpumpsinauxiliaryservices(e.g.lubeoilsystems),manufacturer'sstandardwithdemonstratedexperienceisacceptable.

—AnnexAcontainsdatasheetswhichpurchasersareencouragedtouse(informative).

—AnnexBprovidesguidanceforfactorsaffectingtwinscrewefficiencies(informative).

—AnnexCcontainsaninspector'schecklist(informative)

—AnnexDcontainsinformationonContractDocumentsandEngineeringDesignData(informative)

—AnnexEcontainsformswhichmaybeusedtoindicatevendordrawinganddatarequirements(VDDRs)

(informative)

—AnnexFgivesguidanceregardingnetpositivesuctionhead(NPSH)vsnetpositiveinletpressure(NPIP)(informative).

—AnnexGprovidesatypicalP&IDformultiphasepumpskids(informative).

Thisstandardrequiresthepurchasertospecifycertaindetailsandfeatures.Abullet[]atthebeginningofaparagraphindicatesthateitheradecisionby,orfurtherinformationfrom,thepurchaserisrequired.Furtherinformationshouldbeshownonthedatasheets(seeexampleinAnnexA)orstatedinthequotationrequestandpurchaseorder.

2NormativeReferences

Thefollowingreferenceddocumentsareindispensablefortheapplicationofthisdocument.Fordatedreferences,onlytheeditioncitedapplies.Forundatedreferences,thelatesteditionofthereferenceddocument(includinganyamendments)applies.

APIRecommendedPractice500,RecommendedPracticeforClassificationofLocationsforElectricalInstallationsatPetroleumFacilitiesClassifiedasClassI,Division1,andDivision2

API500,ClassificationofLocationsforElectricalInstallationsinPetroleumRefineries

APIRecommendedPractice520,Sizing,Selection,andnstallationofPressure-RelievingDevicesinRefineries;Part/-SizingandSelection

APIRecommendedPractice520,Sizing,Selection,andInstallationofPressure-relievingDevicesinRefineries;PartIl—Installation

APIStandard526,FlangedSteelPressureReliefValves

APIStandard541,Form-woundSquirrel-cageInductionMotors—500HorsepowerandLargerAPIStandard546,BrushlessSynchronousMachines—500kVAandLarger

1

2APLSTANDARD676

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APIStandard547,General-purposeForm-woundSquirrel-cageInductionMotors—250HorsepowerandLargerAPIRecommendedPractice578,MaterialVerificationProgramforNewandExistingAlloyPipingSystems

APIStandard611,General-purposeSteamTurbinesforPetroleum,Chemical,andGasIndustryServicesAPIStandard613,SpecialPurposeGearUnitsforPetroleum,Chemical,andGasIndustryServices

APIStandard614,Lubrication,Shaft-sealing,andControl-oilSystemsandAuxiliariesAPIStandard671,SpecialPurposeCouplingsforRefineryServices

APIStandard677,General-PurposeGearUnitsforPetroleum,ChemicalandGasIndustryServicesAPIStandard682,Pumps—ShaftSealingSystemsforCentrifugalandRotaryPumps

APIRecommendedPractice686,MachineryInstallationandInstallationDesign

APIRecommendedPractice688,PulsationandVibrationControlinPositiveDisplacementMachinerySystemsAPIStandard691,Risk-basedMachineryManagement

ABMA7,1Shaft,HousingFitsforMetricRadialBallandRollerBearings(ExceptTaperedRollerBearings)ConformingtoBasicBoundaryPlans

ABMA9,LoadRatingsandFatigueLifeforBallBearings

ABMA11,LoadRatingsandFatigueLifeforRollerBearings

ABMA20,RadialBearingsofBall,CylindricalRollerandSphericalRollerTypes-MetricDesignAGMA6013,StandardforIndustrialEnclosedGearDrives

AGMA6091,StandardforGearmotor,ShaftMountedandScrewConveyorDrivesAGMA9000,FlexibleCouplings—PotentialUnbalanceClassification

AGMA9002,BoresandKeywaysforFlexibleCouplings(InchSeries)

ASAS2.19,2MechanicalVibration—BalanceQualityRequirementsofRigidRotors—Part1:DeterminationofPermissibleResidualUnbalance,IncludingMarineApplications

ASME.BoilerandPressureVesselCode(BPVC),3SectionV:Non-destructiveExaminationASME.BPVC,SectionVII:PressureVessels;Division1

ASME.BPVC,SectionIX:WeldingandBrazingQualifications

ASMEB1.1,UnifiedInchScrewThreads(UNandUNRThreadForm)

ASMEB1.20.1,PipeThreads,GeneralPurpose(Inch)

ASMEB16.1,GrayIronPipeFlangesandFlangedFittings(Classes25,125and250)

1AmericanBearingManufacturersAssociation,2025MStreet,NW,Suite800,Washington,DC20036,

2AmericanSubcontractorsAssociation,1004DukeStreet,Alexandria,Virginia22314,

.

3ASMEInternational,3ParkAvenue,NewYork,NewYork10016-5990,

.

PosITIVEDiSPLACEMENTPuMPs-RoTARY3

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ASMEB16.5,PipeFlangesandFlangedFittingsNPS1/2ThroughNPS24Metric/lnchStandard

ASMEB16.11,ForgedFittings,SocketWeldingandThreadedASMEB16.42,DuctileIronPipeFlangesandFlangedFittingsASMEB16.47,LargeDiameterSteelFlanges

ASMEB17.1,KeysandKeyseatsASMEB31.3,ProcessPiping

AWSD1.1,4StructuralWeldingCode—Steel

DIN910:2004,?Heavy-dutyHexagonHeadScrewPlugsEN287,6QualificationTestofWelders—FusionWelding

EN953,SafetyofMachinery—Guards—GeneralRequirementsfortheDesignandConstructionofFixedandMovableguards

HI3.1-3.5,7RotaryPumpStandardsforNomenclature,Definitions,ApplicationsandOperationHI3.68,RotaryPumpTest

IEC60079,ExplosiveAtmospheres

IEEE841,?StandardforPetroleumandChemicalIndustry-SevereDutyTotally-enclosedFan-cooled(TEFC)SquirrelCageInductionMotors—UptoandIncluding370Kw(500Hp)

ISO7,Pipethreadswherepressure-tightjointsaremadeonthethreads—Part1:Dimensions,tolerancesanddesignation

ISO7,Pipethreadswherepressure-tightjointsaremadeonthethreads-Part2:Verificationbymeansoflimitgauges

ISO228-1,Pipethreadswherepressure-tightjointsarenotmadeonthethreads—Part1:Dimensions,tolerancesanddesignation

ISO261,/SOgeneral-purposemetricscrewthreads—Generalplan

ISO262,/SOgeneral-purposemetricscrewthreads—Selectedsizesforscrews,boltsandnuts

ISO724,/SOgeneral-purposemetricscrewthreads—Basicdimensions

ISO965,/SOgeneral-purposemetricscrewthreads—Tolerances

ISO1940-1,Mechanicalvibration—Balancequalityrequirementsforrotorsinaconstant(rigid)state—Part1:specificationandverificationofbalancetolerances

4AmericanWeldingSociety,550NWLeJeuneRoad,Miami,Florida33126,

.

5DeutschesInstitutfürNormungE.V.,Burggrafenstrasse6,10787Berlin,Germany,

www.din.de.

6EuropeanCommitteeforStandardization,AvenueMarnix17,B-1000,Brussels,Belgium,

www.cen.eu.

7HydraulicInstitute300InterpaceParkway,Suite280,3rdfloor,Parsippany,NJ07054,

.

8InternationalElectrotechnicalCommission,3ruedeVarembé,POBox131,CH-1211,Geneva20,Switzerland,

www.iec

ch.

9InstituteofElectricalandElectronicsEngineers,445HoesLane,Piscataway,NewJersey08854,

.

4APLSTANDARD676

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ISO3744,Acoustics—Determinationofsoundpowerlevelsofnoisesourcesusingsoundpressure-Engineeringmethodinanessentiallyfreefieldoverareflectingplane

ISO5753,Rollingbearings—Radialinternalclearance

ISO6708:1995,Pipeworkcomponents—DefinitionandselectionofDN(nominalsize)ISO7005-1,Metallicflanges—Steelflanges

ISO7005-2,Metallicflanges—Castironflanges

ISO8501-1,Preparationofsteelsubstratesbeforeapplicationofpaintsandrelatedproducts—Visualassessmentofsurfacecleanliness—Part1:Rustgradesandpreparationgradesofuncoatedsteelsubstratesafteroverallremovalofpreviouscoatings

ISO14120,Safetyofmachinery-Guards—Generalrequirementforthedesignandconstructionoffixedandmovableguards

ISO14691,Petroleum,petrochemicalandnaturalgasindustries—Flexiblecouplingsformechanicalpowertransmission—General-purposeapplications

MSSSP-55,QualityStandardforSteelCastingsforValves,Flanges,FittingsandOtherPipingComponents—VisualMethodforEvaluationofSurfaceIrregularities

NACEMR0103,10MaterialsResistanttoSulfideStressCrackinginCorrosivePetroleumRefiningEnvironmentsNACEMR0175,MaterialsforUseinH?S-containingEnvironmentsinOilandGasProduction

NACE.CorrosionEngineer'sReferenceBook

NFPA70,11NationalElectricalCode

SSPCSP6,12CommercialBlastCleaning

2.2Allreferencedstandards,totheextentspecifiedinthetext,arenormative.

2.3Notesareinformative,unlesscontainedinafigureortable.

2.4Theeditionsofstandards,codes,andspecificationsthatareineffectatthetimeofpublicationofthisstandardshall,totheextentspecifiedherein,formapartofthisstandard.Theapplicabilityofchangesinstandards,codes,andspecificationsthatoccuraftertheinquiryshallbemutuallyagreeduponbythepurchaserandthevendor

3TermsandDefinitions

Forthepurposesofthisstandard,thefollowingtermsanddefinitionsapply

3.1

alarm

Presetvalueofameasuredparameterthatsendsawarningofaconditionthatrequirescorrectiveaction.

10NACEInternational(formerlytheNationalAssociationofCorrosionEngineers),1440SouthCreekDrive,Houston,Texas77218-8340,

.

"NationalFireProtectionAssociation,1BatterymarchPark,Quincy,Massachusetts02169-7471,

.

12TheSocietyforProtectiveCoatings,4024thStreet,6thFloor,Pittsburgh,Pennsylvania15222,

.

PosITIVEDiSPLAGEMENTPuMPS-ROTARY5

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3.2

anchorbolt

Asleevedstudorthreadedbarusedtoattachthebaseplatetothesupportstructure(concretefoundationorsteelstructure).

3.3

baseplate

Componentonwhichthedrivetrainandpumparebolted,whichisthenfastenedtothesupportstructureusinganchorbolts.

3.4

capacity

Flowratei.e.volumeperunittime.

3.5

certifiedmaterialtestreport

CMTR

Certifiedreportdocumentingtheactualchemicalcompositionorphysicalpropertiesofcriticalmaterials.

3.6

criticalspeed

shaftrotationalspeedatwhichtherotor-bearing-supportsystemisinastateofresonance.

3.7

datumelevation

ElevationtowhichvaluesofNPSHarereferred(concretefoundationorsteelstructuretowhichthebaseplateisattached);alsoseeparagraphdefiningNPSH(see3.39).

3.8

design

Vendor'scalculatedparameter.

NOTEAtermusedbytheequipmentvendortodescribevariousparameterssuchasdesignpower,designpressure,designtemperature,ordesignspeed.Itisnotintendedforthepurchasertousethisterm.

3.9

differentialpressure

Changeinenergyofthepumpedliquidduetoitspressurechangeinthepump.Typically,thedischargepressureminusthesuctionpressure.

3.10

displacement

Volumetransferredfromthesuctiontodischargeperrevolutionoftherotor(s).Inpumpsincorporatingtwoormorerotorsoperatingatdifferentspeeds,thedisplacementisthevolumetransferredperrevolutionofthedrivingrotor.

3.11

drivetraincomponents

Itemoftheequipmentusedinseriestodrivethepump(e.g.motor,gear,turbine,engine,fluiddrive,clutch).

3.12

gasvolumefraction

GVF

Ratioofvolumeofgastothatofthetotalvolumeofthefluid(oil,water,andgas)atpumpsuctiontemperatureandpressure,thefractionbeingexpressedasapercentage.

6APLSTANDARD676

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3.13

hold-downbolt

mountingbolt

Afastener,suchasastudwithnuts,holdingtheequipmenttothebaseplate.

3.14

hydrostatictestpressure

Statictestpressureusedforleaktesting.

3.15

inspectionandtestplan

ITP

Singleproject-specificdocumentusedtoconsolidateallinspectionandtestrequirements,acceptancecriteria,androlesandresponsibilities;typically,withextendedscopeforheavydutypumpsincomplexpackages,

3.16

maximumallowablecasingpressure

MACP

Maximumpressureforwhichthevendorhasdesignedthepressure-containmentcomponentsatthespecifiedoperatingtemperature.

3.17

maximumallowableworkingpressure

MAWP

Maximumcontinuouspressureforwhichthevendorhasdesignedtheequipment(oranyparttowhichthetermisreferred)whenhandlingthespecifiedfluidatthespecifiedmaximumoperatingtemperature.

3.18

maximumcontinuousallowablespeed

Highestrotationalspeed(revolutionsperminute)atwhichthemachine,as-builtandtested,iscapableofcontinuousoperationwiththespecifiedfluidatanyofthespecifiedoperatingconditions.

3.19

minimumdesignmetaltemperature

Lowestmeanmetaltemperature(throughthethickness)expectedinservice,includingoperationupsets,auto-refrigeration,andtemperatureofthesurroundingenvironment.

3.20

multiphasefluid

Aprocessstreamcomprisedoftwoormorephaseswhereonephaseisagas,andonephaseisaliquidandparticulatemaybepresent.

3.21

multiphasepump

MPP

Pumpdesignedtosuccessfullyhandlefluidswithatleastbothgasandliquidpresentintheprocessstream.

3.22

netpositiveinletpressure

NPIP

Minimumpressuredeterminedatthedatumelevationminusthevaporpressureofthefluidatthemaximumoperatingtemperatureatanyspecifiedpoint.

3.23

netpositiveinletpressureavailable

NPIPA

NPIPdeterminedbythepurchaserfromtheNPSHAandsystemdesigndata.

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3.24

netpositiveinletpressurerequired

NPIPR

MinimumNPIPrequiredbythepumptoachievetherequiredperformancewiththespecifiedfluidatanyspecifiedpoint,asdeterminedbyvendor.

3.25

netpositivesuctionhead

NPSH

Totalabsolutesuctionheaddeterminedatthesuctionnozzleandreferredtothedatumelevationminustheheadofthevaporpressureofthefluid.

NOTEItisexpressedasheadofwater,infeet(meters).

3.26

netpositivesuctionheadavailable

NPSHA

MinimumvalueofNPSHdeterminedtobeavailableunderanyspecifiedoperatingcondition,accountingforlinelosses,understeadystateflowconditions.

NOTENPSHAisavalueprovidedbythepurchaserandwhichthepurchaserusestocalculatetheNPIPA(see3.23).NPSHAisafunctiononlyofthesystemupstreamofthepumpandtheoperatingconditionsandisindependentofpumpdesign.

3.27

netpositivesuctionheadrequired

NPSHR

MinimumvalueofNPSHdeterminedtoberequiredunderanyspecifiedoperatingcondition,basedonsteadystateflow.

NOTENPSHRisavalueprovidedbythevendorbytakingtheequipmentrequirements,whicharebasedonthecenterlineofinletreferencepointandadjustingittotheundersideofthebaseplate.ItcorrelatestotheNPIPR(see3.24).

3.28

nominalpipesize

NPS

Designation,usuallyfollowedbyasizenumberdesignationnumber,correspondingapproximatelytotheouts