NPT螺纹简要尺寸管子公称尺寸

1、NPT螺纹简要尺寸管子公称尺寸in1/161/81/43/81/23/411%1%22%33%4管子外径in0.31250.4050.5400.6750.8401.0501.3151.6601.9002.3752.8753.5004.0004.500mm7.910.313.717.121.326.733.442.248.360.373.088.9101.6114.3每英寸牙数27181411%8螺距：mm0.94081.4111.8142.2093.175旋合长度：mm4.0644.1025.7866.0968.1288.61110.16010.66811.07417.32319.45620.

2、85321.438旋合中径：mm7.1429.48912.48715.92619.77225.11731.46240.21846.28758.32570.15986.06898.776111.433NPT代表美国标准管螺纹(NationalPipeTapered),NPTF则是干密封式美国标准管螺纹。两者基本牙型是一样的，不同点是：螺纹牙高不一样。NPT可能有过盈也可能有间隙，但NPTF没有间隙；NPT内外螺纹均为圆锥，而NPTF外螺纹是圆锥，内螺纹则有圆锥、圆柱两种；NPT有右旋也有左旋，NPTF只有右旋一种旋向。NPTFNPTM螺纹是什么意思？NPT：National(American)P

3、ipeThread美国管螺纹。F：Female内螺纹。M：Male外螺纹。国家螺纹管标准ANSIB1.20.1CharacteristicsofNPT（alsoknownasANSI/ASMEB1.20.1PipeThreads,GeneralPurpose）:该标准规定:taperedthread1o47锥形螺纹1度47分truncationofrootsandcrestsareflat顶部和根部的截断面是平的60othreadangle60度的螺纹断面角pitchismeasuredinthreadsperinch单位罗纹数以每英寸计算Note!Pipesizesdonotrefertoa

4、nyphysicaldimensions.Theoutsidediameterofapipeorfittingmustbemeasuredandcomparedtoatableforsizeidentification.A3/4NPTpipethreadhasanoutsidediameter-OD-of1.050inches.备注：管的尺寸不是指物理容积。管的外部直径和属性必须以下面这个表格来确定。例如：一个标准为3/4NPT的管外部直径为1.050英寸。Eachthreadsizehasadefinednumberofthreadsperinch-TPI,orpitch.The3/4NPT

5、pipethreadhas14threadsperinch.BoththeTPIandODofthethreadarerequiredforpositiveidentificationofthreadsizebecausemorethanonesizehavethesameTPI.每种罗纹管每英寸有固定的罗纹数（单位的罗纹数）。TPI或pitch就是单位的罗纹数。3/4NPT标准的罗纹管每英寸有14条罗纹。由于不同的标准中可能会出现同样的单位罗纹数。因此每个标准必须有固定的单位的罗纹数（TPI）和固定的外部直径（OD）。NPT-AmericanStandardPipeTaperThread1）

6、PipeSize管的尺寸(inches)ThreadsperInch单位罗纹数TPI-pitchOutsideDiameter外部直径OD(inches)管的尺寸单位罗纹数外部直径1/16270.3131/8270.4051/4180.5403/8180.6751/2140.8403/4141.050111-1/21.3151/411-1/21.6601-1/211-1/21.900211-1/22.3751/282.875383.5001/284.000484.500585.563686.625888.62510810.75012812.75014814.00016816.0001)Thet

7、aperis1/16inchinaninch,whichisthesameas3/4inchinafoot(angle1o47)1)锥度为每英寸1/16英寸和每英尺3/4英寸是一样的。NPTthreadsarenotinterchangeablewithNPS-NationalPipeStraight-threads.国家螺纹管标准和美国标准直管螺纹NPTthreadsmaylooksimilartoISO7/1threads.However,ISOandNPTthreadsshouldnotbemixed.ISOthreadshave55otaperangleversus60oforNPT.TheNPTrootandcrestconfigurationsarealsodifferentfromISO.ForISOthreadspitchisusuallymeasuredinmillimeters(maybeexpressedinInch).Thepitcharedifferent.国家螺纹管标准可能会像ISO7/1国际标准化组织的