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2023/2/161CHAPTER15YarnProperties2023/2/162

BasicTerminologyOtherProperties本节重点：BasicTerminology-YarnSize-YarnTwist2023/2/163OBJECTIVESTodescribethedifferencesbetweensingleand

plyyarns,andamongyarnsofvaryingsizes.TodiscussthepropertiesassociatedwithstapleandfilamentyamsTodiscusstheimportanceoftheamountand

directionoftwistinayarn,anddiscussthe

differencesinyarnpropertiesthatareassociatedwithyarnconstruction2023/2/164

Keywords全部Newwords1，3-7，9，16-19，21，24，26，28。2023/2/165

Intraditionaltextilemanufacturing,ithasbeencommontofirstmakeyarnfromfibers,thenproduceafabricfromtheyarn.Fabricsproduceddirectlyfromfibers(skippingtheyamstep)representagrowingtextilemarketsegment段，节，片段,buttraditionalwovenandknittedfabricsproducedbyintertwining（捻合，缠结）

yarnsstilldominatethemarket.Inadditiontoknittingyarnsandweavingyarns,sewingthreads,twine合股线，细绳，麻线forwrapping包装packages,andtherope绳索usedtotieasailboat帆船tothedock码头aremadebycombiningfibers.2023/2/166

Knowledgeoffundamentalyarnpropertiesprovidesabasisforunderstandingyarnselectionandmanufacturing.Inthischapter,thebasicterminology术语学ofyarnsispresented.Themeaningsoftermsusedtodescribesizeandtwistinyarnsareexplained,andtheimportanceofsuchpropertiesasstrengthandevennessarepointedout指出.Laterchaptersdescribetheprocessesusedtoformyarnswiththoseproperties.2023/2/167BasicTerminologyASTMD123definesyarnasacontinuousstrand[（绳、线的）股；缕；单纱，须条，绞合]oftextilefibers,filaments,ormaterialinaformsuitableforknitting,weaving,orother-wiseintertwining缠结toformatextilefabric.Yarnstructuresusedforpurposesotherthan不同于，除了fabricproductionmaybereferredtoas

cords（细绳，粗线),ropes绳索andthread.Threadisaspecifictermforyarnusedtojoinfabricsbytheprocesssewing2023/2/168

Whenshort-staplefibersaretwistedtogetherbytheprocessofspinning,theproductmaybereferredtoasastaple（短纤维）orspunyarn（短纤维）.Otherbindingmechanisms,suchaswrapping包裹，包缠shortfiberswithacontinuousfilamentorusinganadhesivetobindfiberstogether,arealsoused:theirproductsalsoreferredtoasspunyarns.2023/2/169

Asinglespunstrand,producedbyoneoftheprocessesabove,isreferredtoasasinglesyarn（单纱，单丝).Whentwoormoresinglestrandsarecombined,theyarnesaplyyarn（合股线）,witheachsinglestrandreferredtoasaply.Thetermsfilament,monofilament,andmultifilament,whichweredefinedinChapter6,areusedtodescribethefibersandtheyarnsproducedfromthem.2023/2/1610

Itispossibletocombinefilamentsandspunstrandstoformmorecomplexyarns（COMPOSITION复合纱).Manytypesofstrandsmaybecombinedtoformnoveltyyarnsfordesigninterestinafabric,orseveralsimplestrandsmaybecombinedtoprovidestrength.AclassificationsystetmforyarnsisshowninTable15.1.2023/2/1611TABLE15.1ClassificationofYarnsSingleYarnsPlyYarnsSpunYarnsHomogeneousspunyarns纯纺纱BlendedyarnsContinuousfilamentyarnsModifiedcontinuousfilamentyarnsCordsorcabledyarn粗索，巨缆Complexyarns复合纱Fancyyarns（花式纱线）2023/2/1612

ThemanufacturingprocessesforspunyarnsareincludedinChapter16.FilamentyarnsandmodificationsoffilamentyarnsaredescribedinChapterI7.Thetermcordisappliedlooselytoavarietyofstrandsincludingcables缆,hawsers粗绳，缆,ropes,andbraidedparachutecords.Inmostcasestheindividualstrands,orplies,oftheseyarnsaresimilarinconstructionandmaybeeitherspunorfilamentproducts.Theyareeventhroughout遍及，贯穿，始终thelengthofthestrandThemethodofjoiningthepliesdetermineswhetherthematerialisdescribedascable,hawser,orrope.Complexandfancyyarnsusuallycombineplieswithdifferentsurfacetextures.TheseyarnsaredescribedingreaterdetailinChapter18.2023/2/1613YARNSIZETheconceptofrelatinglineardensitytothefinessofatextilestrandwasintroducedwiththediscussionoffiberdenierandtexinChapter3.denier,tex,andotherrelatedtermsarealsousedtodenote指示,表示theyarnnumberingsystermsthatdescribethelineardensityofyarns.theseyarnnumberingsystermshavebeendevelopedtodescribetherelativesize,orfineness,ofayarnasamathematicalrelationshipbetweenthelengthofastrandofyarnanditsmass.Themathematicalequationusedtocalculateyarnnumber(纱线支数)mayuselengthasaconstant,makingitadirectnumbering编号systerm,oritmayusemassasaconstant,producinganindirectyarnnumber.2023/2/1614DirectSystems

Indirectyarnnumberingsystems,suchasthedenierandtexsystem,thenumericalsolutiontotheequationincreasesastheyarngetsthicker.Thus,thereisadirectrelationshipbetweenyarnnumberandyarnsize.Thelengthofmaterialremainsconstantandthemass(onwhichtheyarnnumberisbased)changes.Theconstantlengthusedinthedeniersystemis9000meters;inthetexsystemitis1000meters.If9000metersofayarnweighs9grams,itisa9-denieror1-texyarn;if1000metersofitweighs9grams,itisa9-texoran81-denieryarn.

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BothASTMandtheInternationalStandardsOrganization(ISO)havemendedthetexsystemasthestandardyarnnumberingsystem.Amajorreasonforitsadoptionistheeasewithwhichyarnnumberscanbesimplymeasuringalengthofyarnandthencarefullyweighingit.Asanexample,a60mlengthofyarnweighs0.120grams.Withtheformulatex=(grams×1000)/metersitiscalculatedthat1000metersoftheyarnwouldweigh2grams,soitisa2-texyarn.2023/2/1616IndirectSystemsInindirectyarnnumberingsystems,thereisaninverserelationshipbetweenyarnnumberandthefinenessoftheyarn.Themassoftheyarnremainsconstantandthelength(onwhichtheyarnnumberisbased)varies,so,asthediameteroftheyarnincreases,theyarnnumberdecreases.Manyindirectyarnnumberingsystemsareinusethroughouttheworld.Thecotton,woolen,andworsted精纺systemsarethethreeusedmostfrequentlyintheUnitedStates.2023/2/1617

Traditionally,thecottonsystemwasusedtodescribetheyarnsproducedonshort-staplecottonspinningmachinery,andthewoolenandworstedsystemswereusedtodescribeyarnsspunonlong-staplewoolspinningmachinery,andthewoolenandworstedsystemisusedtodescribeyarnsspunonothersystemsaswell,becausemanufacturer'sfamiliaritywiththesystemhaspreconditioned前提v.预处理theconceptofaspecificsizeassociatedwithacottonyarnnumber.2023/2/1618

Thetermyarncountisoftenusedinsteadofthetermyarnnumberinindirectyarnnumberingsystems.Cottoncountofyarnsappearsinthetextileliterature,abbreviatedasNe(for“number,English”)or,lessfrequently,cc(for“cottoncount（英制棉纱支数)”).Thecottoncountisthenumberof840-ardhanks(绞，亨克)thatweighapound.2023/2/1619

Ahank绞isaskein(绞纱，绞丝）ofyarn;an840-yardcottonhankisaskeinofyarnmeasuring840yards.If10hanksofyarn(8400yards)weigh1pound,theyarncountis10.Themostcommonwaytowritethisis“10Ne,”indicatingthecountoftheyarnandthesystemusedtodeterminethecount.Theformulaforcottoncountiscottoncount=yards/(840×pounds)

Themorehanksittakestoweighapound,thehighertheyarncountandthefinertheyarn.A1Neyarnisacoarseyarn,whereasa100Neyarnisaveryfineyarn;thereisaninverserelationshipbetweenyarncountandyarnfineness.Highcountsincottonyarnsindicatefineyarns;lowcountsindicatecoarseyarns.2023/2/1620

Thefinenessofretail零售的cottonandcotton-blendsewingthreadsisgivenincottoncount.Themostwidelyavailableproducttodayislabeledas"50."Insomeareas,very-fine-count100threadisavailableforsewingfine,sheerfabrics.Thecountofyarnsspunonalong-staplesystemmaybedesignatedbyavarietyofsystems.Twoofthemostcommonaretheworstedcountandthewoolenrun（粗纺毛纱支数),basedon560-yardand1600-yardhanks,respectively.Themassineachcaseis1

pound.Aworstedcountwouldbecalculatedwiththeformulaworstedcount（精纺毛纱支数）=yards/(Ibs×560)2023/2/1621DesignatingPly（纱线股数，合股）Asingle-ply,orsingles,yarnisdesignatedwithaslash斜线markandanumeralone(/1)ortheyarnnumberandtheletter“s.”Thus,either“20/1”or“20s”couldbeusedtorefertoa20cotton-countsinglesyarn.Atwo-plyyarnisdesignatedby“/2.”A60/3Nesewingthread(线)isayarnmadebycombiningthree60-countcottonpiles.Ifthethree-plyyarnweremeasuredandweighedasasingleyarn,itwouldappeartobea20Neyarn.2023/2/1622YARNTWIST(n.捻，v.捻合)Fibersareusuallytwistedtogetherbytheprocessofspinningtoproduceayarnthatwillwithstandtherigors严厉，苛刻ofweavingorknitting.Thedirectioninwhichthefibersaretwistedandtheamountoftwistinsertedaffectthepropertiesofyarnsandtheproductsthatcanbemadefromtheyarns.Twistaffectsstrength,luste,rabrasionresistance,hand,absorbency,andflexibility.2023/2/1623DirectionTwistisinsertedbyrotatingfiberstrandsineitheraclockwise顺时针orcounterclockwisedirection.ThedirectionoftwistisdefinedbytheletterSorZ(Figure15.1).AnS-twistyarnisoneinwhichthespiraloftheyarnisparalleltothecenterbaroftheletterS:likewisefora

Z-twistyarn.Aspindlerotatingcounterclock-wiseproducesanStwist:aspindlerotatingclockwiseproducesaZtwist.2023/2/1624FIGUBE15.1DiagramofSandZtwistsinyarns2023/2/1625

MostyarnsspunoncottonsystemshaveaZtwist.Thetraditiongoesbacktomedieval中世纪的，原始的times.Theconsumerprotectionlawsofthecraft工艺，手艺guilds行会，协会decreed颁布，法令，政令thatcottonandlinenwouldbespunwithanStwist.Inmoderntimes近代，现代,becausemostofthepeoplewhooperateandrepairspinningframesareright-handed,theequipmentisdesignedtospinZ-twistyarnstomaximizetheirefficiency.2023/2/1626AmountTheamountoftwistinayarnisexpressedasturnsperinch(tpi)ofyarnlength.Yarnsthathavelowlevelsoftwistaresofterandhavemoreloft,orbulk蓬松:theyareusuallyweakerthanyarnswithmoretwist.Ingeneral,theshorterthefiberbeingspun,themoretwistisrequiredtogivestrength.Atsomepoint,however,theoptimumtwistwillhavebeeninserted,andadditionalturnswilldecreasethestrengthoftheyarn.Pasttheoptimum,thefibersintheyarnaremoreperpendicularthanparalleltothelengthoftheyarn.2023/2/1627

Theoptimumtpiinayarnisdirectlyrelatedtoitsfineness.Fineyarnsusuallyrequireahighertpithancoarseyarn.Toachievesimilarpropertiesinyarnsofvariouscounts,theconceptofthetwistmultiple,ortwistmultiplier(TM捻系数),isused.TheTMistheratioofthetpitothesquarerootofthecottoncountoftheyarn,anditmaybeusedasameasureofthehardness硬度oftwistintheyarn.

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StatedasaformulaTM=tpi/sqr(Ne)whereTM=twistmultiplierTpi=turnsperinchtwistNe=cottonyarncountCottonknittingyarnsarespunwitha2to3TM;fillingyarnsforweavingmayhavea3to4TM;andwarpyarnsforweavingmayhavea4to5TM.Hard-twistyarnssuchascrepeyarns绉纱arespunwitha5to7TM.Whentoomuchtwistisaddedtotheseyarns,theyarnmaydeveloptorque扭矩andkink扭结，弯曲andsnarl缠结,makingitdifficulttoweaveorknit.2023/2/1629

Liveliness回弹性andbalancearetermsusedtodescribethistendencyofyarnstodeveloptorque.Abalancedyarn(Figure15.2)isonethatwillhanginaloopwithoutkinking扭结,doubling成双,ortwistingitself.Alively活泼的,orunbalanced,yarnisonewithenoughtwisttosetupatorqueeffect.Itwilluntwistandretwistonitself,oftensnarlingorkink(扭结，纠缠，小辫子；扭结纱；纬缩）ing.2023/2/1630

Onemethodofcontrollingtorqueandusingittoadvantageistocombinepliestwistedinoppositedirectionstoformapliedyarn.Thefinalyarnhasthepropertiesdescribedinatightlytwistedyarn,butthelivelinesshasbeencontrolled.Itisalsopossibletouseatwist-settingfinish,whichallowsmillstoweavehigh-twistcrepeyarns.2023/2/1631OtherPropertiesDURABIUTYTensilestrengthandabrasionresistanceareimportantindeterminingthedurabilityofyarnsforweavingandknittingandinpredictingtheperformanceofyarnsinotherenduses.Variationsinyarnconstruction(forexample,finenessandtwist),inadditiontofibercontent,affectthedurabilityofayarn.2023/2/1632FiberCohesion（内聚力，抱合力）Yarnstrengthdependssomewhatonfibercohesion.

Iflongfibersaremadeparallel(aligned)toprovidemaximumcontactbetweenfibers,itispossibletoproduceacohesiveyarnstrongerthantheyarnproducedbyspinningthesamefiberswithoutaligning矫正(路线),(直线)对准them.Longfibersalsoproduceamorecohesive,andhencestronger,yarnthanshortfibers.2023/2/1633TwistTwistaffectsbothstrengthandabrasionresistance.Lowtwistproducesayarnthatpullsmoreeasily.Thefibersarenotheldinthestrandasfirmly,sowithanydisturbance(骚动,动乱,打扰,干扰,骚乱,搅动abrasion)morefiberendsprotrudefromthesurfaceoftheyarn.Theyattractotherbitsoffiber,producingpillsonthesurfaceoftheyarn.Pillingcausedbyabrasionisoftenaproblemwithyarnsmanufacturedfromshortfiberslooselytwistedtogether.2023/2/1634

Astwistinayarnincreases,strengthincreasesandpillingdecreases.Asarule,strengthandabrasionresistanceimprovetoapointandthenbegintodeclineasthefibersemoreperpendiculartothelengthwiseaxisoftheyarn.2023/2/1635Ply

AfinesingleyarnisweakerthanacoarseyarnofthesameTM.Onemethodofincreasingthestrengthoffineyarnsistoproduceapliedyarnofthesameapparentcount.Withweavingmachinesoperatingatincreasinglyhigherspeeds,fine-countplyyarnsarebeingusedinplaceofsingleyarnstoreducefabricdefectscausedbyyarnbreakageduringmanufacture.Sewingthreadisoftenproducedbycombiningthreepliesofveryfinecounttoproduceayarnwithhighstrength,abrasionresistance,andtwistbalance.Highstrengthisalsorequiredinpackagingtwines合股线,细绳,麻线andropes.Thecombiningofseveralpliesproducesamaterialstrongerthanasingleplyofsimilartotaldiameter.2023/2/1636EVENNESSIfthediameterofayarnisconstantthroughoutitslength,theyarnisperfectlyeven.Fewyarnsexhibitperfectevenness;mosthaveanoccasionalthickorthinplaceinthestrand,andinyarnstheremaybeneps（棉结，毛结，麻粒）orknots,offibersthatfromthickplaces.Suchyarnsmayproducefabricdefectsthataffectappearanceandperformance.Whenunevenplacesrecur复发,重现,再来,anundesirablepatternmaybeproducedinafabric.Controlofevennessisanimportantcomponentofyarnqualitycontrol(Figure15-3).2023/2/1637FIGURE15.3TestingtheevennessofyarnswithUsterequipmentintheCottonIncorporatedlab­oratories.2023/2/1638

Insomecasesunevennessisdesirable.Manynoveltyyarnsareproducedbyincludingthickandthinplaces,orslubsofwithintheyarn.Tobeeffectivetheirrecurrencemustbecontrolled.2023/2/1639BLENDINGFIBERSItispossibletobalancedesirableandundesirablepropertiesbyblendinggenericfibersdur