螺纹的技术标准

目录TOC\o"1-5"\h\z修订履历3介紹41.1目的4範圍4螺牙8定义6分类82.3精度等级82.4螺纹标注92.5基本尺寸10铝合金10铝合金成分10公差12ISO12JIS12DIN12GB145参考文件15修订履历1.介绍目的定义产品的外观信息,包括:装配的公差,特殊的外观要求以及在允许范围内的和通用标准的偏差。范围适用于公司所生产的所有压铸件产品，客户特别规定的除外。2.螺牙2.1定义螺纹：在圆柱或圆锥表面上,沿着螺旋线所形成的具有规定牙形的连续凸起。内螺纹：在圆柱或圆锥内表面上所形成的螺纹。外螺纹：在圆柱或圆锥外表面上所形成的螺纹。有效螺纹：由完整螺纹和不完整螺纹组成的螺纹，不包括螺尾。公称直径：代表螺纹尺寸的直径。大径：与外螺纹牙顶或内螺纹牙底相切的假想圆柱或圆锥的直径。用d（外螺纹）或D（内螺纹）表示。中径：一个假想圆柱或圆锥的直径，该圆柱或圆锥的母线通过牙形上沟槽和凸起宽度相等的地方。该假想圆柱或圆锥称为中径圆柱或中径圆锥。中径用d2（外螺纹）或D2（内螺纹）表示。小径：与外螺纹牙底或内螺纹牙顶相切的假想圆柱或圆锥的直径。用di（外螺纹）或D1（内螺纹）表示。螺距：相邻两牙在中径线上对应两点间的轴向距离。螺纹精度：由螺纹公差带和旋合长度共同组成的衡量螺纹质量的综合指标。旋向：螺纹有右旋和左旋两种。内外螺纹旋合时，顺时针旋入的为右旋，逆时针旋入的为左旋。2.2分类螺纹密封（55°）非螺纹密封（55°）60°,1°47〃55°1°7〃圆柱内螺纹圆柱管螺纹圆锥管螺纹圆柱管螺纹圆锥内螺纹圆锥外螺纹英制RcRRp/Ps（旧）G/PFPT美制NPS美制NPSNPT国标RcRRp/PsG/PFNPT类型牙型放大图特征

代号标注示例用途及说明最常用的一种联接螺纹，直径相同时，细牙螺纹的螺距比粗牙螺纹的螺距小，粗牙螺纹不注螺距管道联接中的常用螺纹，螺距及牙型均较小，其尺寸代号以in为单位，近似地等于管子的孔径。螺纹的大径应从有关标准中查出，代号R表示圆锥外螺纹，R表示C圆锥内螺纹，R表P类型牙型放大图特征

代号标注示例用途及说明最常用的一种联接螺纹，直径相同时，细牙螺纹的螺距比粗牙螺纹的螺距小，粗牙螺纹不注螺距管道联接中的常用螺纹，螺距及牙型均较小，其尺寸代号以in为单位，近似地等于管子的孔径。螺纹的大径应从有关标准中查出，代号R表示圆锥外螺纹，R表示C圆锥内螺纹，R表P示圆柱内螺纹梯形螺纹TrvjN上一C-JI匚常用的两种传动螺纹，用于传递运动和动力，梯形螺纹可传递双向动力，细螺纹粗螺纹超细螺纹公制M英制UNFUNCUNEF常用螺纹的种类2.3精度等级螺纹精度是由螺纹公差带和旋合长度共同组成的衡量螺纹质量的综合指标。螺纹公差带代号包括中径公差带与顶径公差带代号。公差带代号是由表示其大小的公差等级数字和表示其位置的字母组成。如6H,6g等。螺纹公差带代号标注在螺纹代号之后，中间用一分开。如螺纹的中径公差带与顶径公差带代号不同，则分别注出。前者表示中径公差带，后者表示顶径公差带。如螺纹的中径公差带与顶径公差带代号相同，则只注一个代号。名称螺纹等级螺纹种类国家标准公制牙JIS1级2级3级公螺纹ISO4h6g8g母螺纹4H.5H5H.6H7H美制牙公螺纹JIS3A2A1AISO母螺纹JIS3B2B1BISO英制牙2级3级4级2.4螺纹标注当螺纹精度要求较高时，除标注螺纹代号外，还应标注螺纹公差带代号和螺纹旋合长度。2.4.1螺纹标记的标注格式为：螺纹代号——螺纹公差带代号（中径、顶径）——旋合长度1）公差带代号由数字加字母表示（内螺纹用大写字母，外螺纹用小写字母），如7H、6g等，应特别指出，7H，6g等代表螺纹公差，而H7，g6代表圆柱体公差代号。2）旋合长度规定为短（用S表示）、中（用N表示）、长（用L表示）三种。一般情况下，不标注螺纹旋合长度，其螺纹公差带按中等旋合长度（N）确定。必要时，可加注旋合长度代号S或L,如“M20-5g6g—L”。特殊需要时，可注明旋合长度的数值，如“M20-5g6g—30”。2.4.2、普通螺纹普通粗牙螺纹：特征代号M+公称直径+旋向+螺纹公差带代号（中径、顶径）一一旋合长度普通细牙螺纹：特征代号M+公称直径*螺距+旋向+螺纹公差带代号（中径、顶径）——旋合长度右旋螺纹省略不注，左旋用“LH”表示。M16—5g6g表示粗牙普通螺纹，公称直径16,右旋，螺纹公差带中径5g,大径6g，旋合长度按中等长度考虑。M16x1LH—6G表示细牙普通螺纹，公称直径16,螺距1,左旋，螺纹公差带中径、大径均为6G，旋合长度按中等长度考虑。2.4.3、管螺纹的标注

格式为：特征代号（圆柱管螺纹用G表示，圆锥管螺纹用NPT表示）+尺寸代号+公差等级代号+旋向G1A--LH表示英制非螺纹密封管螺纹，尺寸代号1in，右旋，公差等级为A级。Rcl/2表示英制螺纹密封锥管螺纹，尺寸代号l/2in，右旋。基本尺寸2.5.1公制螺纹公制细牙内螺纹规格标准径公制细牙内螺纹规格标准径6H精度DmaxDminM2.5*0.352.152.1842.121M3.0*0.352.652.6842.621M3.5*0.353.153.2213.121M4.0*0.503.503.5993.459M4.5*0.504.004.0993.959M5.0*0.504.504.5994.459M5.5*0.505.005.0994.959M6.0*0.755.255.3785.188M7.0*0.756.256.3786.188M8*0.757.257.3787.188M8*1.007.007.1536.917M9*0.758.258.3788.188M9*1.008.008.1537.917M10*0.759.259.3789.188M10*1.009.119.1538.917M10*1.258.758.9128.647Mll*0.7510.2510.37810.188Mll*1.0010.0010.1539.917M12*1.0010.7510.91210.647M12*1.2510.5010.67610.376M12*1.5011.0011.15310.917M14*1.0013.0013.15312.917M14*1.2512.7512.91212.647M14*1.5012.5012.67612.376M15*1.014.0014.15313.917M15*1.5013.5013.67613.376M16*1.015.0015.15314.917M16*1.5014.5014.67614.376M17*1.016.0016.15315.917M17*1.5015.5016.67615.376公制粗牙内螺纹规格标准径6H精度DmaxDminM1.4*0.31.101.161.075M1.6*0.351.251.3211.221M1.8*0.351.451.5211.421M2.0*0.41.601.6791.567M2.2*0.451.751.8381.713M2.5*0.452.052.1382.013M3.0*0.52.502.5992.459M3.5*0.62.903.012.85M4.0*0.73.303.4223.242M4.5*0.753.753.8783.688M5.0*0.84.204.3344.134M5.5*0.55.005.0994.959M6.0*1.005.005.1534.917M7.0*1.006.006.1535.917M8.0*1.256.756.9126.647M9.0*1.257.757.9127.647M10*1.508.508.6768.376Mll*1.509.509.6769.376M12*1.7510.2510.4410.106M14*2.0012.0012.2111.835M15*1.5013.5013.67613.375M16*2.0014.0014.2113.835M17*1.5015.5015.67615.376M18*2.5015.5015.74415.294M20*2.5017.5017.74417.294M22*2.5019.5019.74419.294M24*3.0021.0021.25220.752M27*3.0024.0024.25223.752M30*3.5026.5026.77126.211公称尺寸大径中径小径UNC粗牙UNF公称尺寸大径中径小径UNC粗牙UNF细牙0-801.5241.3181.1811-641.8541.5981.4251-721.8541.6261.4372-562.1841.891.6942-642.1841.9281.7553-842.5152.1721.9413-562.5152.222.0244-402.8452.4332.1564-482.8452.5022.2715.5.2统一标准螺纹公称尺寸大径中径小径UNC粗牙UNF细牙'9/16-1214.28812.91311.996'9/161814.28813.37112.761‘5/1114.87514.37613.376‘5/81814.87514.95814.348'3/4-1019.05017.39916.301‘3/41619.05018.01917.337‘7/8-922.22520.39119.169'7/81422.22521.04620.265'1-825.40023.33821.963M18*1.516.5016.67616.376M18*2.016.0016.2115.835M20*1.019.0019.15318.917M2O*1.5O18.5018.67618.376M20*2.018.0018.2117.835M22*1.021.0021.15320.917M22*1.5020.5020.67620.376M22*2.020.0020.2119.835M24*1.023.0023.15322.917M24*1.5022.5022.67622.376M24*2.022.0022.2121.835M25*1.024.0024.15323.917M25*1.523.5023.67623.376M25*2.023.0023.2122.835M26*1.5024.5024.67624.376M27*1.026.0026.15325.917M27*1.525.5025.67625.376M28*1.027.0027.15326.917M28*1.526.5026.67626.376M28*2.026.0026.2125.835M30*1.029.0029.15328.917M3O*1.5O28.5028.67628.376M30*2.028.0028.2127.835M30*3.027.0027.25226.752

5-403.1752.7642.487‘1-1225.40024.02623.1095-443.1752.7092.55111/8-728.57526.21824.6486-323.5052.992.64711/81228.57527.20126.2846-403.5053.0942.81711/4-731.75029.39327.8238-324.1643.653.30711/41231.75030.37629.4598-364.1643.7083.40113/8-634.92532.17430.343‘10-244.8264.1383.6813/81234.92533.55132.63410-324.8264.313.96711/2-638.10035.34933.518‘12-245.4864.7984.34111/21238.10036.72635.809‘12-285.4864.8974.50313/4-544.45041.15138.951'1/4-206.355.5244.972-41/250.80047.13544.690'1/4-286.355.7615.36721/4-41/257.15053.48551.0395/16-187.9387.0216.41121/2-463.50059.37556.626‘5/16247.9387.2496.79223/4-469.85065.72562.976'3/8-169.5258.4947.805‘3/476.20072.07569.326'3/8-249.5258.8378.39731/4-482.55078.42575.6767/16-1411.1129.9349.14931/2-488.90084.77582.0267/16-2011.11210.2879.73833/4-495.25091.12588.376‘1/2-1312.711.4310.584'4-4101.60097.47594.726‘1/2-2012.711.87411.326UNEF螺牙基本尺寸代号螺纹牙数标准径大径小径1/4325.65.695.4865/16327.17.2647.0873/8328.78.8658.6617/162810.210.33810.1351/22811.811.93811.7099/162413.213.38613.1325/82414.814.98614.7323/42017.817.95817.6787/8202121.13320.8531202424.30824.0285.5.3NPT、G螺纹基本尺寸NPT螺纹基本尺寸G(PF)螺纹基本尺寸NPT螺纹基本尺寸代号螺纹牙数大径代号螺纹牙数大径中径小径代号螺纹牙数大径中径小径‘1/16277.8957.1426.389‘1/16287.7237.1426.5611/82710.2429.4898.7361/8289.7289.1478.5661/41813.61612.48711.3581/41913.15712.30111.4453/81817.05515.92614.7973/81916.66215.80614.951/21421.22319.77218.3211/21420.95519.79318.6313/41426.56825.11723.6665/81422.91121.74920.587111.533.22831.46129.6943/41426.44125.27924.11711/411.541.98540.21838.4517/81430.20129.03927.87711/211.548.05446.28744.5211133.24931.7730.291211.560.09258.32556.55811/81137.89736.41834.93921/2872.69970.15967.61911/41141.9140.43138.9523888.60886.06883.52811/21147.80346.32444.85431/28101.31698.77696.23613/41153.74652.26750.78848113.973111.433108.89321159.61458.13556.65658140.952138.412135.87221/41165.7164.23162.75268167.792165.252162.71221/21175.18473.70572.22688218.441215.901213.36123/41181.53480.05578.576108272.312269.772267.23231187.88486.40584.926128323.032320.492317.95231/211100.3398.85197.3725.5.4RP螺纹基本尺寸RP螺纹基本尺寸代号螺纹牙数大径中径小径‘1/16287.7237.1426.5611/8289.7289.1478.5661/41913.15712.30111.4453/81916.66215.80614.951/21420.95519.79318.6313/41426.44125.27924.11711133.24931.7730.29111/41141.9140.43138.95211/21147.80346.32444.84521159.61458.13556.65621/21175.18473.70572.22631187.88486.40584.9262.6挤牙丝攻攻牙底孔径公制螺纹（非圆丝攻）美制螺纹（非E圆丝攻）螺纹标准2级螺纹用下孔径螺纹标准2级螺纹用下孔径

准铝合金牌号化学成分（％）SiFeCuMnMgZnNiSnAlADC129.6-12.0W1.31.53.5W0.5W0.3W1W0.5W0.2余量ADC6W1.0W0.6W0.100.40.62.64.0W0.4W0.1W0.1余量A41311.013.0W1.3W1W0.35W0.1w0.05W0.5w0.15余量A3807.5-9.5W1.33.04.0W0.5W0.1W3W0.5w0.35余量精度最大-最小（咬合率）M1.75*0.35RH41.54-1.58(100-75%)M2*0.4RH41.81-1.85精度最大-最小（咬合率）M1.75*0.35RH41.54-1.58(100-75%)M2*0.4RH41.81-1.85(100-75%)M2.3*0.4RH42.11-2.15(100-75%)M2.5*0.45RH42.28-2.33(100-75%)M2.6*0.45RH42.38-2.43(100-75%)M3*0.5M3.5*0.6RH52.76-2.81(100-75%)RH53.20-3.26(100-75%)M4*0.7RH63.65-3.70(100-85%)M5*0.8M6*lRH64.95-4.66(100-85%)RH75.48-5.57(100-85%)3.铝合金3.1铝合金成分NO.2-56UNC-64UNFRH41.96-2.02(100-65%)RH31.98-2.04(100-65%)NO.3-48UNC-56UNFRH42.25-2.32(100-65%)RH42.29-2.357(100-65%)NO.4-40UNC-48UNFRH52.52-2.60(100-70%)RH42.57-2.64(100-70%)NO.5-40UNC-44UNFRH52.86-2.93(100-70%)RH42.88-2.95(100-70%)NO.6-32UNC-40UNFRH53.09-3.17(100-70%)RH53.19-3.26(100-70%)NO.8-32UNC-36UNFRH63.76-3.84(100-75%)RH53.80-3.88(100-75%)NO.10-24UNC-32UNFRH64.26-4.35(100-80%)RH54.41-4.48(100-80%)NO.12-24UNC-28UNFRH64.92-5.01(100-80%)RH55.00-5.08(100-80%)1/4-20UNC-28UNFRH65.66-5.76(100-80%)RH55.86-5.93(100-80%)最大-最小（咬合率）4.公差制造零件时，为了使零件具有互换性，要求零件的尺寸在一个合理范围之内，由此就规定了极限尺寸。制成后的实际尺寸，应在规定的最大极限尺寸和最小极限尺寸范围内。允许尺寸的变动量称为尺寸公差，简称公差。标准公差：标准公差IT的数值由基本是标准所列的用以确认公差带大小的任一公差。标准公差分为20个等级，即：IT01、IT02、IT1至IT18。IT表示标准公差，数字表示公差等级。IT01公差数值最小，精度最高；IT18公差数值最大，精度最低。基本尺寸：设计给定的尺寸。极限尺寸：允许尺寸变动的两个极限值，它是以基本尺寸为基数来确定的。偏差：某一实际尺寸减其基本尺寸所得的代数差。极限偏差：即指上偏差和下偏差。最大极限尺寸减其基本尺寸所得的代数差就是上偏差；最小极限尺寸减其基本尺寸所得的代数差就是下偏差。尺寸公差：允许尺寸的变动量。即最大极限尺寸与最小极限尺寸之差；也等于上偏差和下偏差代数差的绝对值。4.1ISOISO2768-1(GB/T1804-92)表1线性尺寸的极限偏差数值公差Limitsinmmfornominalsizesinmm符号描述0.5-33〜66~3030~120120~40040010001000~20002000~4000ffine±.05±.05±.1±.15±.2±.3±.5—mmedium±.1±.1±.2±.3±.5±.8±.2±ccoarse±.2±.3±.5±.8±.2±±vverycoarse—±.5±.5±.5±±±Fornominalsizesbelow0,5mmthelimitmeasuresaretobeindicateddirectlyatthenominalmeasure.表2倒角半径与倒角高度尺寸的极限偏差数值公差Limitsinmmfornominalsizesi