工程机械搅拌设备用称重传感器的选型外文文献翻译、中英文翻译、外文翻译

MechanicalmixingequipmentworkswiththeselectionofloadcellThispaperengineeringmachinerymixingequipmentweighingsystemandthebasicrequirementsforspecialrequirements,proposedconstructionmachinerymixingequipmentweighingsystemusedtobeconsideredwhenthesensorseveralissues,thefocusofsensorprotectivestructureontheconstructionmachinerymixingequipmentreliabilityofoperation,pointingoutthatthecodegenerationIPTableprotectivelevelscannotcovermechanicalmixingequipmentworksfullprotectionofthesensorrequirements.Recommendationsdifferenttypesofmixingequipmentselectionofdifferentdefensivecapabilitiesofthesensor.WeighingSystemsensorsnormallyusedintheweighingsystemtoconsidertheamountoflimitedaccuracy,sensorinstallationspace,theenvironmentmayaffectthesensor,loadandthetypeofsensor,suchasthelifespanofvariousfactors.Engineeringmachinerymixingequipmentweighingsystemisnoexception.Theweighingsystemisdifferentbecauseofdifferentdemands,differentworkingconditions,tobeconsideredbyfocusingondifferentissuesonly.Engineeringmachinerymixingconcretemixingequipmentusuallyincludefloor(stations),theasphaltmixingplant,stabilizedsoilmixingconcretemixingplantsandshipsatsea,mixingthemwithconcretefloor(stations)themosttypical.Belowtheconcretemixingplant(stations)asanexampleforanalysis.1concretemixingplant(station)onthebasicrequirementsWeighingSystem1.1accurateweighingerroronthestrengthofconcreteisstronglyinfluenced,inparticularwater-cementratiomeasurementprecision,becausestrengthandwater-cementratioislinear.Therelevantnationalstandards,cement,water,additives,theadmixtureofdynamicmeasurementaccuracyof±1%,sand,stonedynamicmeasurementaccuracyof±2%.Quickmeetmixingstationdutycyclerequirements.varietythatmoneytothetypeofpre-selection,tofacilitatethetransformationtoadapttoavarietyofdifferentratioandcapacityrequirements.simplestructureweighingdevicestosimplestructure,solidandreliable,stableperformance,easyoperation.Clearly,theuseofelectronicweighingsystemsensormachineryweighingmorethanmeettherequirements.Therefore,theloadcellfloorintheconcretemixingstationstobemorewidelyused.However,objectivelyspeaking,comparedwiththemechanicalleverscalesinthe"solidandreliable,stableperformance,"asasensorelectronicweighingsystemhasmuchworktodo.2concretemixingstationsfloorintheloadcelloperatingconditionsForcommerceandthegeneralmeasurementofelectronicscalesagreatdifferenceis,inconcretemixingstationsfloorloadcellinaveryadverseoperatingconditions,stressenvironmentisverycomplex,andthegeneralelectronicproductscomparedtotheoperatingenvironment,agreaterrandomness.ambienttemperatureandhumidityConcretemixingstationisnormallyopenfloorinstallation,sensormaybesubjecttothesunandrain,temperaturedramaticchanges.Andmanyconstructionprojectsareinverybadnaturalconditionsinthemountainsorremoteareas.Therefore,wemustconsidergreatertemperaturerangeandhigherhumidityconditions.Concreteintheproductionprocessneedswater.Inthedeliveryofwaterandweighingprocessandalsohavealotofwaterinthegas,insomeformwithinrelativelysmallhumidenvironment.StirinthetemperaturecontrolintheHouse,therearehigh-temperatureandlow-temperatureconditionsofthedifferentrequirementsofcondition.Runninginthesummerwhenlow-temperatureconditiontothezero-belowcoldwindand力口冰stirring,thenbuildingacondensedwaterwillbewelldemonstratedhighhumiditybuilding.dustConcreteintheproductionprocessrequiresalargeamountofcement,coalashandtheappropriateamountofadmixture.Thesewereinthetransportationandpowderweighingprocesswillproducedust.Eventheaggregate,inthecourseoftransmissionhavealsodust.Someofthesedustsensorwillbeattachedtothesurface.Thedustandwatervaporinthecommonrole,thesensorwillbemoreseriouscorrosion.Therefore,thedamagepowderweighingsensorsusuallyweighthantheothersensorsmorefrequently.ShockandVibrationInthefeedprocess,theimpactofaggregatewillhave.Sensorsshouldbeabletobear5gacceleration.Stirintheprocess,willhavesustainedvibration,andvibrationwouldhavefatiguedamage.man-madeenvironmentMan-madeenvironmentistheproductreliabilitydesignoneofthefactorsthatmustbeconsidered.ConcreteMixingfloorinstalledattheconstructionsiteingeneral.Large-scaleuseoftemporaryworkersonsite,ofwhichaconsiderablenumberoftemporarylowlevelofeducation,lackofthenecessaryskills.Intermsoffacilities,suchasthemaintenanceandcleaningwork,thesensormaybeinthehigh-pressurewatersputtering,misoperationcausedoverload,andsoon.Clearly,thesensorshouldbeinsuchanenvironmentandalong-termreliableundertheconditionsoftheoperationistocarryoutsomespecialdesign.Thesebasicrequirementsandoperatingconditionscanbeusedasconcretemixingplant(stations)bytheloadcellselectionbasis.Threeconcretemixingplant(stations)tousewhenweighingsensortobeconsideredbytheSelectionProblems3.1weighingsensorpayloadcapacitydeterminationWeighingsensorpayloadcapacityusuallyHoppersensorratedload=+ratedthemselvesthatweight(0.6~0.7)xonlyafewsensorsInfactpeopleinthechoiceofsensorintegratedcapacityevenwhentheyconsiderthesizeandimpactloadselectedsafetyfactor.Safetyfactorwiththechoiceofsensorsensitivitycloselyrelated.Domesticandforeigncommonstrainloadsensorsensitivitymajorityof2mV/V,butthereare1mV/V,suchascolumnsensor;Also3mV/V,assomecantileversensorandsensorplateCentral;Twistedringsensorusually2.85mV/V.Stirupstairsintheuseofsensorsarebasically2mV/V.3.2weighingthechoiceofsensoraccuracyThechoiceofsensoraccuracyoftheweighingsystemtomeettheaccuracyrequirements,isnotone-sidedpursuitofthehighlevelsensoraccuracy.Inmulti-sensorcombinationusedonlywhenitsintegratederror△r=6/VnWhere,6onlyasinglesensoraccuracy,theuseofcombinationsofnisonlyafewsensors.CurrentlystirringupstairspopularS-typesensor,thecantileversensor,thesensorplatering,linear,hysteresis,repeatability,andtemperaturesensitivityeffectsofcreep,andotherkeyindicatorsvastmajorityofmanufacturersareisbetterthan0.05%,themajorityofmanufacturersbetterthan0.03%,somemanufacturersbetterthan0.02%.Itsintegratedsinglesensorerrorofclosetoorbetterthan0.1%.Multi-sensorcombinationonlyafteritsintegratederrorevensmaller.Itcanbesaidthatthegeneralloadcellmanufacturersofproductstomeettherequirements.Previously,manymanufacturersstirringfloor,itsprovisionsstaticaccuracyoftheweighingsystem,respectively0.1%and0.3%respectively.Thus,theuseofsingle-sensorweighingonly,individualindicatorsof0.05%ofthesensorwillsatisfy0.3%precisionweighingrequirements.Theuseofthreeovertheweigh-sensor,singleindicators0.05%sensorscanalsomeet0.1%accuracyrequirements.Itmustbepointedoutisthattheaccuracyoftheweighingsystemisstaticprecision,whiletheconcreteisthenationalstandardsrequiredynamicaccuracy,whichisduetotheconstantweighingofrawmaterialsforthematerialinthebodyofgravityweighingtheimpactoferrorsincreasedsignificantly.Above0.1%and0.3%respectively,theabilityofstaticaccuracyreached1%and2%ofthedynamicaccuracyforfeedingsystemwiththedesign.Now,manymanufacturersprovisionsoftheaccuracyofitsweighingsysteminthe0-ratedweighingthatmoneywithinthecement,water,additives±1%,sand,stone±2%.Notes,ready-mixedconcretenationalstandardsrequirethatphysicalmeasurementaccuracy,andgeneralmeasurementinstruments0~20%oftherelativeerrorgreater,orconcretemixingplant(station)providestheindustrystandardinthe20~100%oftheweightingofthemeetcement,water,additives±1%,sand,stone±2%ofthemorepracticalmeasurestoallowsomedeviation.Amorereasonableapproachistheuseofprecisionweighinginstrumenttaggingindustryterminologytoexpressthatasacumulativehopperscalesshouldbeusedinautomaticweighingaccuracyofthegradingmarks1.0and2.0.Suchscaletestprojectinlinewiththepurposes,includingbothmaterialstesting(determiningtheaccumulatederror)alsoincludesstatictest.AutomaticWeighingatitsmaximumallowableerrorinTable1.Criteriausedinastaticloadtestandnon-automaticweighing,shouldmeettherequirementsinTable2.Usually1.0weighdesignforthe1000points,2.0Balanceofdesignfor500points.Wecanseethattherangeinthehigh-1.0scaleerroris0.15%,2.0Balanceoferroris0.3%,notmanufacturersthanbeforeprovisionsof0.1%and0.3%statichighaccuracy.Butinthelowrangeofaccuracyisindeedincreased.Undersuchcircumstancestheneedtoconfirmtheselectioninthelowrangeofthesensorcanalsomeettherequirements.Accordingtoweighthedegreeofchoiceofthesimplestsensoris1,000pointsmethodofselectionof1000attheweigh-insensors,500hoursoftheweigh-selection500pointsofthesensors.Nationalstandardsinweighingsensoraccuracyistousethedegreetoexpress,butbecauseofvariousreasons,mostproductionplantsthatstillusesingleindicatorsensoraccuracy.Accordingtoindividualuserstocalculateindicatorsintegratedprecisionerror.Chooseuptroublepoint.Theconcretemixingofforeigndevelopedcountriesfloorgeneralwithprecisionweighingsystemtothedegreethat,inthe1000Indexing.Theymayberelatedtotheuseofhigh-performanceconcretehighproportionofthe.Astheeconomyandthecontinuousdevelopmentoftechnology,ultra-high-risebuilding,longbridges,large-scalewaterconservancyprojects,aswellasotherexposedtotheharshenvironmentintheconstructionofconcreteperformanceraisedhigherandhigherdemands,concretetechnologyhasalsoenteredthehigh-techage,theproportionofhigh-performanceconcretecontinuousimprovement.Inadditiontoproducinghigh-performanceconcretecorrectselectionofrawmaterials,determineareasonableprocessparameters,theconstructiontechnologyofcontrolisalsoveryimportant.Stiringredientsintheconcretefloor,theaccuracyofthesystemisimportant.3.3sensorstructureformsofchoiceCommonlyusedapull-typeS-shapedsensors,theplatecenterringandringcruciatetendons,suchasplate.Crosscenterringreinforcementplatehighaccuracysensors,anti-partialcontainsexcellentperformance,buthigherpricesarenormallyonlyusedinhigh-precisionmeasurementoccasions.MixingupstairsiscommonlyusedS-typesensorsandsensorplateCentral.S-typesensorwhichitshighaccuracy,anti-partial-carryingcapacity,atthesametimecanbringoverloadprotection,thewiderangeofuseoftheadvantagesofthelargest.Popularpressuresensorofacantileverbeam,Spoke,column,bridge,suchasring-twisting.Consideredaccuracy,rangeofinstallation,priceandotherfactors,thevastmajorityofproductionplantstochoosestirringfloorofthecantilever.3.4loadtypeofconsiderationConcreteproductionmainlyusessand,gravel,cementandwater,additives,admixture.Severalmaterialsweightheimpactofafewstoneasthegreatest.Inthelargefamilyofelectronicscales,suchisnotthegreatestimpact,thesensorcangenerallybearoverloadsituation.Fromtheauthorofthesurvey,thesensoroverloadanddamageduetothesituationfromtimetotime.Forexample,acontrolsystemfault,causingheavymaterialdisposalandthenext,causingoverload.Alsotheuseofhumanfactorsduringtheoverload,especiallythesmallrangesensorfortheoperatorstampedeScaleFrameandoverloaddamagethingshappenfromtimetotime.Thereforesensor,sensorswhetherWeighingSystemOverloadProtectionforthereliableoperationofacertaininfluence.Sensorperformanceindicatorshavetwowiththis,firstallowingoverload,firstlimitoverload.Allowoverloadreferstoshedtheload,sensorperformanceindicatorsunchanged.Limitoverloadreferstotheloadsensordoesnotproduceharmfulpermanentmechanicaldeformation.Generaloverloadsensorallowsfor150%,andoverloadlimitin200%~300%.Someofthesensorwithoverloadprotectionarelikelytoexceedthescopeofone.SensorssuchasPutianfactoryCFCKN-1-becauseoftheirspecialsensordesign,allowingtheloadashighas500%.Suchfrequentoverloadsensorinthecasecanreliablywork.3.5sensorprotectionratingSensorIPprotectionlevelsthatareusuallyused.GeneralsensormanufacturerssaidtheirproductshavereachedIP67level,asmallnumberofmanufacturersofsomeproductstoIP68level.WeknowthattheIPcodeisexpressedbynotmorethan72.5kVvoltageelectricalproductsprotectiveshellofgrading.Nationalstandards"GB4208-93shellprotectionlevels",IP67meanstheproductcandust,andagainstshort-termimmersion;IP68meanstheproductcandust,andagainstcontinueddivingimpact.Itmustbepointedoutisthatsuchprotectiondoesnotincludemechanicaldamage,corrosion,orexternalinfluencessuchashumidenvironmentalconditions.Usuallyinvolvingsuchprotectionprovidedbytherelevantproductstandards.Weighingsensorsandgeneralelectricalproductsandsecondaryproductsofdifferentinstruments,itisalsoaforcecomponentintheoperationofconstantlybeingproducedandtheroleofdeformation.Thereisalsolikelytobeshock,impactorimpactsuchamechanicaldamage,dustandwatervaportothemorecommonunderseverecorrosionandinextremelyhumidconditionsrunning.ThisisGB4208-93underthetestconditionsarequitedifferent.Haveencounteredsuchasituation:aweigh-oreminesonselectedimportssensor,alargesteelladleweighontheselectionofaninternationallyrenownedbrandssensors,arewelded,sealedandverybeautiful,toIP68level.Butinactuallifeveryshortscene.Inthelastresortcircumstances,thetrialofPutiansensorplantproducts.Theaccidentcameastheresultoftheirservicelifeinexcessofimportssensor.Oneinalargesteelladleweighonthesensorhasbeeninoperationforsevenyears,arestillrunning.Inthesetwoexamples,thefactistheprotectionofdistinction.First,therewerestillnoshellcasing;Second,welddesign.Third,sealingmaterials.Generallyspeaking,thedesignisbetterthannoshellcasingdesign;Thedesignoftheweldseamshouldbeavoidedasfaraspossiblebyforce.Intheunavoidablecircumstances,willhavetocheckweldstrength,inparticularthefatiguestrength.Fatiguecracksarecausedminortidalleadentry,theimportantreasonsforsensorfailure.Theaforementionedweldingofaworld-renownedbrandsensoratthescenesealedthereasonsfortheshortlifeofexcessiverelianceontheweldingissealed,theinternalstraintabletsonlyathinplasticseallevel,onceweldcracks,moisturesensorontheroleintherapidfailure.Insealingmaterialsneedtoberemindedthat,throughIP67half-hoursoakingtestsensorsmaynotbeabletoknow,sensor-standarddampheatinthe12-cycletest.Subjecttotheimpactofpricecompetition,manycanceledsensorplantprotectionframes,pull-typesensorisevenworse.ThecurrentdomesticproductionofS-typesensor,thesensorplateCentralalmostcanceledshell.Indeed,onmanyoccasionsthereisnothingwrongwithdoingso.However,insuchaconcretemixingplantenvironmentalconditions,maynotbethebestchoice.IplantforthedesignoftheThreeGorgesProjectmixingplantproductionCFCKN-1Caseclosureweldingsensorservicelifeupto10years.WehaveseentheUnitedStatesandJapanupstairsEuropeconcretemixingwiththepull-typesensoriswiththeprotectionofthemajorityoftheshell.Theythinkthatshouldbeasemi-permanentsensordevices,lifeshouldnotbelessthan106times.Yearsofpracticehasprovedthat,CFCKN-1-S-typesensorandsensorordinarycomparedtoaminimumthefollowingadvantages:shellthickness,andagainstmechanicaldamage,inparticularthestronganti-collisionoutside;welddepth,corrosionresistancetowearalongtime;overloadprotectiongapiswithintheshell,donotdustordebrisaccumulatedbyblocking;Weighingsensordesignisareasonableshellweighingdevice"solidandreliable,stableperformance,"animportantguaranteeforselection,mustbeseriouslyconsidered.360differenttypesofmixingtheselectionofloadcellbreakdownLargeandmedium-sizedwaterconservancyprojectsofconcretemixingplant,urbancommercialconcretemixingplant,smallirrigationworksandhighwayconstructioninthecountyusedintheconcretemixingplantsizespecifications,theuseofcontinuous-time,theinstallationlocationsenvironmentalconditionsareverydifferentfromtheproductionofconcreteperformancerequirementsareverydifferent.Therefore,thereliabilityofthesensor,theprotectivepropertiesingradesalsohavedifferentrequirements,shouldbetreateddifferently.Longhoursofcontinuousoperation,harshenvironmentalconditionsandtheproductionofhigh-performanceconcretemixingplantshouldchoosereliability,ahighlevelofprotectionsensors.Theremainingrequirementscanbeappropriatelyreduced.Forrunningontheconcretemixingvesselatsea,itisalsonecessarytoconsidertherequestofanti-saltspray,notindividuallyelaboratehereonthe.工程机械搅拌设备用称重传感器的选型本文阐述了工程机械搅拌设备称重系统的基本要求和特殊要求，提出了工程机械搅拌设备称重系统选用传感器时需要考虑的几个问题，重点分析了传感器防护结构对工程机械搅拌设备运行可靠性的影响，指出IP代码所代表的防护等级不能涵盖工程机械搅拌设备对传感器的全部防护要求。建议不同类型的搅拌设备选用不同防护能力的传感器。称重系统中选用传感器通常要考虑称重系统的量限、准确度、传感器的安装空间、周围环境对传感器的可能影响、加载的类型以及传感器的寿命等诸方面因素。工程机械搅拌设备的称重系统也不例外。只是不同的称重系统由于要求不同，工作条件不同，所要考虑的问题侧重点有所不同罢了。工程机械搅拌设备通常包括混凝土搅拌楼（站）、沥青搅拌站、稳定土拌和厂以及海上混凝土搅拌船等，其中以混凝土搅拌楼（站）最为典型。下面就以混凝土搅拌楼（站）为例进行分析。混凝土搅拌楼（站）对称重系统的基本要求准确称量误差对混凝土的强度影响很大，特别是水灰比计量精度，因为强度和水灰比是线性关系。相关国家标准规定，水泥、水、外加剂、掺合料的动态计量精度为±1%，砂、石料的动态计量精度为±2%。快速满足搅拌楼站工作循环的要求。种类多称量值预选的种类要多，变换要方便，以适应多种配比和不同容量的要求。结构简单称量装置要结构简单，牢固可靠，性能稳定，操作容易。显然，采用传感器电子称重系统较之机械秤更能满足要求。因此，称重传感器在混凝土搅拌楼站中得到了越来越广泛的应用。但是，客观地说，与机械杠杆秤相比，在“牢固可靠，性能稳定”方面，传感器电子称重系统还有很多工作要做。混凝土搅拌楼站中称重传感器的运行条件与一般用于商贸计量的电子秤的一个很大的不同之处在于，混凝土搅拌楼站中称重传感器处于相当恶劣的运行条件中，应力环境十分复杂，与一般的电子产品的运行环境相比，有更大的随机性。环境温度和湿度混凝土搅拌楼站通常是露天安装，传感器可能遭受日晒雨淋，温度剧烈变化。而不少工程建设项目是在自然条件相当恶劣的山区或边远地区。所以，必须考虑更大的温度范围，更高的湿度条件。混凝土在生产过程中需要水。在水的输送和称量过程中也会产生不少水气，在一定的小范围内形成较为潮湿的环境。在温控搅拌楼中，则有高温工况和低温工况的不同要求。夏天运行在低温工况时要通入零度以下的冷风以及加冰搅拌，这时楼内会出现冷凝水，足见楼内湿度之高。粉尘混凝土在生产过程中需要大量的水泥、煤粉灰以及适量的外加剂。这些粉状物在输送和称量过程中会产生粉尘。即使是骨料，在输送过程中也有粉尘产生。这些粉尘有一部分会附着在传感器表面。在粉尘和水气的共同作用下，传感器将受到较为严重的腐蚀。所以，粉料秤传感器的损坏通常要比其他秤的传感器更频繁一些。冲击与振动在进料过程中，砂石料会产生冲击。传感器应能承受5g的加速度。在搅拌过程中，会产生持续的振动，而振动会产生疲劳破坏。人为环境人为环境是产品可靠性设计时必须考虑的因素之一。混凝土搅拌楼一般安装在施工现场。工地上大量使用临时工，其中相当多的临时工文化水平较低，缺少必要的技能。在设备的维修和清洗等工作中，很有可能发生传感器受到高压水的溅射，误操作引起过载等情况。显然，传感器要在这样的环境条件下长期可靠的运行，是要进行一些特殊设计的。上述基本要求和运行条件可以作为混凝土搅拌楼（站）用称重传感器的选型的依据。混凝土搅拌楼（站）用称重传感器选型时需要考虑的几个问题称重传感器载荷容量的确定称重传感器载荷容量通常按下式计算传感器额定载荷=料斗自重＋额定称重量（0.6~0.7）x传感器只数事实上人们在选择传感器容量时往往还要综合考虑冲击载荷的大小以及选定安全系数.安全系数的选择又与传感器的灵敏度有密切关系．国内外常见的应变式称重传感器灵敏度多数为2mV/V,但是也有1mV/V的，如柱式传感器；也有3mV/V的，如部分悬臂梁式传感器和板环式传感器；扭环式传感器则通常是2.85mV/V。目前在搅拌楼上使用的传感器基本上都是2mV/V的。称重传感器准确度的选择传感器准确度的选择以满足称量系统的准确度要求为准，不必片面追求过高的传感器准确度等级。在多只传感器组合使用时，其综合误差按下式计算6r=6/Yn式中，6为单只传感器的准确度，n为组合使用的传感器只数。目前搅拌楼上常用的S型传感器、悬臂梁式传感器、板环式传感器，其线性、滞后、重复性、灵敏度温度影响、蠕变等主要指标绝大多数厂家均优于0.05%，大多数厂家优于0.03%，部分厂家优于0.02%。其单只传感器的综合误差都接近或优于0.1%。多只传感器组合后其综合误差就更小了。可以说一般称重传感器生产厂家的产品都能满足要求。以前，不少搅拌楼生产厂家规定其称重系统的静态精度分别为0.1%和0.3%。这样，对于使用单只传感器的秤而言，单项指标为0.05%的传感器就可以满足0.3%精度的秤的要求。对于使用三只以上传感器的秤而言，单项指标0.05%的传感器也能满足0.1%精度的要求。需要指出的是，上述精度是称重系统的静态精度，而混凝土国家标准要求的是动态精度，这是由于原材料不断地向称量机构供料在重力的冲击下称量误差明显增加。上述0.1%和0.3%的静态精度能否保证分别达到1%和2%的动态精度还与供料系统的设计有关。现在，不少厂家规定其称重系统的精度在0~额定称量值的整个称量范围内为水泥、水、外加剂±1%，砂、石料±2%。须知，预拌混凝土国家标准要求的是实物计量精度，而一般计量仪器在0~20%范围相对误差较大，因此，还是混凝土搅拌楼（站）的行业标准中规定的20~100%的称量段满足水泥、水、外加剂±1%，砂、石料±2%的计量允许偏差更为实际一些。更为合理的精度标注方式是采用衡器行业的术语来表述，即作为累计料斗秤，应采用自动称量准确度的等级标志1.0和2.0。这类秤的检定项目与用途相适应，既包括物料试验（确定累计误差）也包括静态检定。其自动称量时的最大允许误差见表一。在用标准载荷进行静态检定和进行非自动称量时，应满足表二的规定。通常将1.0级秤设计为1000分度，2.0级秤设计为500分度。可以看出，在高量程端1.0级秤的误差为0.15%，2.0级秤的误差为0.3%，并不比以前厂家规定的0.1%和0.3%静态精度高。但是在低量程段精度要求确实是提高了。在这种情况下需要确认所选用的传感器在低量程段能否也满足要求。按秤的分度数选择传感器最简单的方法就是1000分度的秤选用1000分度的传感器，500分度的秤选用500分度的传感器。称重传感器国家标准中准确度就是用分度数来表示的，但是由于多方面的原因，目前大多数生产厂仍用单项指标表示传感器的精度。用户再根据单项精度指标算出综合误差。选用起来麻烦一点。国外发达国家的混凝土搅拌楼称重系统精度一般用分度数来表示，规定为1000分度。可能与他们使用高性能混凝土所占比例高有关。随着经济和技术的不断发展，超高层建筑、超长桥梁、大型水利工程以及其他暴露在严酷环境中的建筑对混凝土的性能提出了越来越高的要求，混凝土技术也进入了高科技时代，高性能混凝土的应用比例不断提升。生产高性能混凝土除了要正确选用原材料、确定合理的工艺参数外，施工工艺的控制也是十分重要的。混凝土搅拌楼中配料系统的准确度是其中重要的一环。传感器结构形式的选择常用的拉式传感器有S形，板环式以及中心十字筋板环式等。中心十字筋板环式传感器精度