公英制螺纹对照表

英语和公制对照表“英寸”统一螺纹在“英寸”国家广泛使用。这种类型的螺纹分为三个系列：粗螺纹系列UNC、细螺纹系列UNF、UNFF超细螺纹系列，外加一个固定螺距系列UN。标记方法：螺纹直径.每英寸齿数系列代码.精度等级示例：粗齿系列3/8-16unc-2a细齿系列3/8-24unf-2a超细齿系列3/8-32 UNFF-2a固定齿距系列3/8-20 UN-2a第一个数字3/8表示螺纹的外径，单位为英寸，换算成公制单位毫米乘以25.4，即3/3/825.4=9.525毫米；第二和第三位数16、24、32和20是每英寸的齿数(长度为25.4毫米的齿数)；排在第三位的文本代码为UNC、UNF、UNFF和UN，最后两个2A是精度等级。根据统一的螺纹标准，公称尺寸可以有不同的螺距。例如，1/2有13颗牙齿，16颗牙齿，20颗牙齿和32颗牙齿。该标准规定，13颗牙为粗牙，20颗牙为细牙，28颗牙为超细牙。16齿和32齿被称为恒定齿距，这与粗齿和细齿没有区别。英制螺纹外径公制对照表英寸公制英寸公制英寸公制4#2.91-5/841.2754-5/8117.4755#3.21-3/444.454-3/4120.656#3.51-7/847.6254-7/8123.8257#3.9250.851278#4.22-1/853.9755-1/4133.3510#4.82-1/457.155-3/8136.52512#5.52-3/860.3255-1/2139.714#/1/46.352-1/263.55-5/8142.8751/83.1752-5/866.6755-3/4146.051/46.352-3/469.855-7/8149.2255/167.9362-7/873.0256152.43/89.525376.26-1/4158.757/1611.1133-1/879.3756-3/8161.9251/212.73-1/482.556-1/2168.2759/1614.2883-3/885.7256-5/8171.455/815.8753-1/288.96-3/4174.6253/419.053-5/892.0256-7/8177.87/822.2253-3/495.257184.15125.43-7/898.1257-1/4187.3251-1/828.5754101.67-3/8190.51-1/431.754-1/4107.957-1/2193.6751-3/834.9254-3/8111.1257-5/8196.851-1/238.14-1/2114.37-3/4200.025英美联盟公制规格底部出口规格底部出口1-64UNC1.55M1.0*0.250.752-56UNC1.8M1.1*0.250.853-48UNC2.1M1.2*0.250.954-40UNC2.3M1.4*0.31.15-40UNC2.6M1.6*0.351.256-32UNC2.8M1.7*0.351.358-32UNC3.4M1.8*0.351.4510-32UNC4.1M2.0*0.41.610-24UNC3.9M2.2*0.451.7512-24UNC4.5M2.3*0.41.914-20UNC5.1M2.5*0.452.1516-18unc6.6M2.6*0.452.238-16UNC8M3.0*0.52.5716-14UNC9.4M3.0*0.62.412-13UNC10.8M3.5*0.62.9916-12UNC12.2M4.0*0.73.358-11UNC13.6M4.0*0.753.2534-10UNC16.5M4.5*0.73.878-9UNC19.5M5*0.84.21 - 8UNC22.2M5*0.94.1118-7UNC25M6*1.05114-7UNC28.2M7*1.06138-6UNC30.8M8*1.256.8112-6UNC34M9*1.257.8134-5UNC39.5M10*1.58.52-412UNC45.2M11*1.59.5英美螺纹的螺距是根据每英寸长度的齿数计算的。外径根据螺纹牌号的首码数计算(4#、5#、6#、7#、8#、10#、12#的特殊外径见表1)示例：1/4-20 UNC1/4*25.4=6.35(螺纹外径)25.4/20=1.27(间距)M12*1.7510.3M14*2.012M16*2.014M18*2.515M20*2.517M22*2.519M24*3.021M27*3.024M30*3.526.5螺纹电极外径和螺距参考表英美联盟公制规格外径规格外径1-64UNC1.45M1.0*0.250.652-56UNC1.7M1.1*0.250.753-48UNC2.0M1.2*0.250.854-40UNC2.2M1.4*0.31.05-40UNC2.5M1.6*0.351.156-32UNC2.7M1.7*0.351.258-32UNC3.3M1.8*0.351.3510-32UNC4.0M2.0*0.41.510-24UNC3.8M2.2*0.451.6512-24UNC4.4M2.3*0.41.814-20UNC5.0M2.5*0.452.0516-18unc6.5M2.6*0.452.138-16UNC7.9M3.0*0.52.4716-14UNC9.3M3.0*0.62.312-13UNC10.7M3.5*0.62.8916-12UNC12.1M4.0*0.73.358-11UNC13.5M4.0*0.753.1534-10UNC16.4M4.5*0.73.778-9UNC19.4M5*0.84.11 - 8UNC22.1M5*0.94.0118-7UNC24.9M6*1.04.9114-7UNC28.1M7*1.05.9138-6UNC30.7M8*1.256.7112-6UNC33.9M9*1.257.7134-5UNC39.4M10*1.58.42-412UNC45.1M11*1.59.4英美螺纹的螺距是根据每英寸长度的齿数计算的。示例：1/4-20 UNC1/4*25.4=6.35(螺纹外径)2