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【英文标准名称】:Industrial-processcontrolvalves—Part8-4:Noiseconsiderations—Predictionofnoisegeneratedbyhydrodynamicflow
【原文标准名称】:工业过程控制阀.第8-4部分:噪声考虑.液体动力流产生噪声的预测
【标准号】:BSEN60534-8-4-2005
【标准状态】:现行
【国别】:英国
【发布日期】:2007-07-31
【实施或试行日期】:2007-07-31
【发布单位】:英国标准学会(GB-BSI)
【起草单位】:BSI
【标准类型】:()
【标准水平】:()
【中文主题词】:控制工艺学;控制阀;电气工程;排放;流体力学的;流体动力学(水);实验室试验;数学计算;计算方法;噪声;噪声排放;噪声测量;设备;预测;过程自动化;过程控制;声级;声功率;声压;声压级;符号;单位;阀门
【英文主题词】:Controltechnology;Controlvalves;Electricalengineering;Emissions;Hydrodynamic;Hydrodynamics;Laboratorytests;Mathematicalcalculations;Methodsofcalculation;Noise;Noiseemissions;Noisemeasurements;Plant;Precalculation;Processautomation;Processcontrol;Soundlevel;Soundlevels;Soundpower;Soundpressure;Soundpressurelevel;Symbols;Units;Valves
【摘要】:ThispartofIEC60534establishesamethodtopredictthenoisegeneratedinacontrolvalvebyliquidflowandtheresultingnoiselevelmeasureddownstreamofthevalveandoutsideofthepipe.Thenoisemaybegeneratedbothbynormalturbulenceandbyliquidcavitationinthevalve.Partsofthemethodarebasedonfundamentalprinciplesofacoustics,fluidmechanics,andmechanics.Themethodisvalidatedbytestdata.Noisegeneratedbyflashingflowisnotconsideredinthisstandard.Thetransmissionloss(TL)equationsarebasedonanalysisoftheinteractionbetweenthesoundwavesinsidethepipeandthecoincidencefrequenciesinthewallofthepipetakingintoaccountthatcommercialpipetolerancesallowarelativelywidevariationinthethicknessofthepipewall.Idealstraightpipingisassumed.Themethodcanbeusedwithallconventionalcontrolvalvestylesincludingglobe,butterfly,cage-type,eccentricrotary,andmodifiedballvalves.Testssofarhaveonlybeenconductedwithwater.Theapplicabilityofthismethodforfluidsotherthanwaterisnotknownatthistime.Thisstandardconsidersonlynoisegeneratedbyhydraulicturbulenceandfluidcavitation.Itdoesnotconsideranynoisethatmightbegeneratedbymechanicalvibrations,unstableflowpatterns,andunpredictablebehaviour.Inthetypicalinstallation,verylittlenoisetravelsthroughthewallofthecontrolvalvebody.Thenoiseismeasuredatthestandardmeasuringpointof1mdownstreamofthevalveand1mawayfromtheoutersurfaceofthepipe.Thispredictionmethodhasbeenvalidatedwithtestresultsbasedonwatercoveringmorethan90%ofallknownvalvetypesatinletpressuresofupto15bar.Thismethodisconsideredaccuratewithin??5dB(A)exceptintherangeofxF=xFz??0,1,whenxFziscalculatedusingequations(3a)or(3b).
【中国标准分类号】:N16
【国际标准分类号】:17_140_20;23_060_40;25_040_40
【页数】:30P.;A4
【正文语种】:英语


【英文标准名称】:Roundglassesforwatches-Mineralglasses-Denominations,essentialdimensions
【原文标准名称】:小型表的圆形表壳玻璃.矿物玻璃.名称.基本尺寸
【标准号】:DIN8253-3-1981
【标准状态】:作废
【国别】:德国
【发布日期】:1981-06
【实施或试行日期】:
【发布单位】:德国标准化学会(DIN)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:尺寸;作标记;密封件;无机玻璃;表面玻璃;表;玻璃
【英文主题词】:mineralglasses;seals;watch-glasses;marking;watches;dimensions;glass
【摘要】:
【中国标准分类号】:Y11
【国际标准分类号】:39_040_10
【页数】:2P;A4
【正文语种】:德语