无屑攻牙前钻头使对照表(抽牙用)

無屑攻牙前鑽頭使對照表(抽牙用)

螺丝攻牙钻孔径和滚造径对照表

螺丝攻牙钻孔径和滚造径对照表 本表所推选之钻头孔径，是针对攻牙加工时，能够很容易的了解钻孔直径；而依抿市售之标准钻头所选定的，在使用钻头的情况下，由于钻头的形状及尺寸、精度、被钻孔之材质等，对于所钻孔的尺寸、精度有很大的影响，所以使用本表之钻孔径，若有不当之处，应视实际壮况适当的变更钻头直径，本表是依据2级牙 最大最小最大最小G4-G6G7-G8G9G4-G6G7-G8G9 硬材软材M1.0*0.250.750.7850.729M12*1.011.0011.15310.917M1.0*0.250.860.88-No 2 - 56UNC 1.94-- W1/8 - 40 2.65 2.60M1.1*0.250.850.8850.829M12*0.511.5011.52011.400M1.1*0.250.960.98-No 3 - 48 2.23-- W5/32 - 32 3.25 3.20M1.2*0.250.950.9850.929M14*1.512.5012.67612.376M1.2*0.25 1.06 1.08-No 4 - 40 2.50-- W3/16 - 24 3.75 3.70M1.4*0.30 1.00 1.142 1.075M14*1.013.0013.15312.917M1.4*0.30 1.24 1.25-No 5 - 40 2.83-- W1/4 - 20 5.10 5.00M1.6*0.35 1.25 1.321 1.221M15*1.513.5013.67613.376M1.6*0.35 1.41 1.43-No 6 - 32 3.07-- W5/16 - 18 6.60 6.50M1.7*0.35 1.35 1.421 1.321M15*1.014.0014.15313.917M1.7*0.35 1.51 1.53-No 8 - 32 3.73 3.77- W3/8 - 168.007.90M1.8*0.35 1.45 1.521 1.421M16.1.514.5014.67614.376M1.8*0.35 1.61 1.63-No10 - 24 4.24 4.30- W7/16 - 149.409.30M2.0*0.40 1.60 1.679 1.567M16*1.015.0015.15314.917M2.0*0.40 1.78 1.80-No12 - 24 4.90 4.96- W1/2 - 1210.7010.50M2.2*0.45 1.75 1.838 1.713M17*1.515.5015.67615.376M2.2*0.45 1.95 1.98-1/4 - 20- 5.72- W9/16 - 1212.3012.00M2.3*0.40 1.90 1.979 1.867M17*1.016.0016.15315.917M2.3*0.40 2.08 2.10-5/16 - 18-7.24- W5/8 - 1113.7012.50M2.5*0.45 2.10 2.138 2.013M18*2.016.0016.21015.835M2.5*0.45 2.25 2.28-3/8 - 16-8.748.81 W3/4 - 1016.7013.50M2.6*0.45 2.20 2.238 2.113M18*1.516.5016.67616.976M2.6*0.45 2.35 2.38-7/16 - 14-10.2010.30 W7/8 - 919.5016.50M3.0*0.50 2.50 2.599 2.459M18*1.017.0017.15316.917M3.0*0.50 2.73 2.75-1/2 - 13-11.2711.82 W1 - 822.4019.30M3.0*0.60 2.40 2.440 2.280M20*2.018.0018.21017.835M3.5*0.60 3.17 3.20-No 2 - 64UNF 1.97-- W1-1/8 - 725.0024.80M3.5*0.60 2.90 3.010 2.850M20*1.518.5018.67618.376M4.0*0.70 3.62 3.65 3.69No 3 - 56 2.27-- W1-1/4 - 728.3028.00M4.0*0.70 3.30 3.422 3.242M20*1.019.0019.15318.917M5.0*0.80 4.56 4.60 4.64No 4 - 48 2.56-- M4.0*0.75 3.25 3.326 3.106M22*2.020.0020.21019.835M6.0*1.00 5.45 5.50 5.55No 5 - 44 2.66-- M4.5*0.75 3.80 3.878 3.688M22*1.520.5020.67620.376M7.0*1.00 6.45 6.50 6.55No 6 - 40 3.16-- M5.0*0.80 4.20 4.334 4.134M22*1.021.0021.15320.917M8.0*1.257.317.387.44No 8 - 36 3.78-- M5.0*0.90 4.10 4.170 3.930M24*2.022.0022.21021.835M10*1.509.189.259.32No 10- 32 4.39 4.43- M6.0*1.00 5.00 5.153 4.917M24*1.522.5022.67622.376M10*1.259.319.389.44No 12 -28 4.99 5.04- M7.0*1.00 6.00 6.153 5.917M24*1.023.0023.15322.917M12*1.7511.0411.1211.211/4 -28 5.85 5.90- SM1/8 - 40 2.735 - 2.688M8.0*1.25 6.80 6.912 6.647M25*2.023.0023.21022.835M12*1.2511.3111.3811.445/16 -247.367.41- SM1/8 - 44 2.769 - 2.722M9.0*1.257.807.9127.647M25*1.523.5023.67623.3763/8 -24-9.00- SM9/64 - 40 3.128 - 3.083M10*1.508.508.6768.376M25*1.024.0024.15323.9177/16 -20-10.4810.54 SM11/64 - 40 3.855 - 3.805M11*1.509.509.6769.376M26*1.524.5024.67624.3761/2 -20-12.0712.13 SM3/16 - 32 4.205 - 4.155M12*1.7510.3010.44110.160M27*2.025.0025.21024.835 SM3/16 - 28 4.143 - 4.093M14*2.0012.0012.21011.835M27*1.525.5025.67625.376SM7/32 - 32 5.003 - 4.955M16*2.0014.0014.21013.835M27*1.026.0026.15325.917 SM15/64 - 28 5.325 - 5.570M18*2.5015.5015.74415.294M28*2.026.0026.21025.835 SM1/4 - 40 5.890 - 5.735M20*2.5017.5017.74417.294M28*1.526.5026.67626.376SM1/4 - 28 5.721 - 5.366M22*2.5019.5019.74419.294M28*1.027.0027.15326.917最大最小 SM9/32 - 28 6.508 - 5.648M24*3.0021.0021.25220.752M30*3.027.0027.15226.752最大最小PS 1/16 - 28 6.50 6.632 6.490 SM11/32 - 288.092 - 8.432M27*3.0024.0024.25223.752M30*2.028.0028.21027.835No 1-64(1.854) 1.55 1.582 1.425PS 1/8 - 288.508.6378.495 SM3/8 - 288.880 - 8.015M30*3.5026.5026.77126.211M30*1.528.5028.67628.376No 2-56(2.184) 1.80 1.871 1.695PS 1/4 - 1911.4011.54911.341 SM7/16 - 2810.466 - 10.401M30*1.029.0029.15328.917No 3-48(2.515) 2.10 2.146 1.941PS 3/8 - 1915.0015.05414.846 SM7/16 - 1610.037 - 9.967M32*2.030.0030.21029.835No 4-40(2.845) 2.30 2.385 2.157PS 1/2 - 1418.5018.77318.489 SM1/2 - 2011.819 - 11.749M32*1.530.5030.67630.376No 5-40(3.175) 2.60 2.697 2.487PS 3/4 - 1424.0024.25923.975 SM9/16 - 2013.400 - 13.425最大最小M33*1.030.0030.25229.752No 6-32(3.505) 2.80 2.895 2.642PS 1 - 1130.2030.47130.111 M1.0*0.20.800.8210.783M33*2.031.0031.21030.835No 8-32(4.166) 3.40 3.530 3.302PS 1-1/4 - 1138.8039.13238.772 M1.1*0.20.900.9210.883M33*1.531.5031.67631.376No 10-24(4.826) 3.90 3.962 3.683PS 1-1/2 - 1144.8045.02544.665 M1.2*0.2 1.00 1.0210.983M35*1.533.5033.67633.376No 12-24(5.486) 4.50 4.597 4.344PS 2 - 1156.5056.83656.476 M1.4*0.2 1.20 1.221 1.183M36*3.033.0033.25232.752 1/4 - 20 5.10 5.257 4.979 M1.6*0.2 1.40 1.421 1.383M36*2.034.0034.21033.835 5/16 - 18 6.60 6.731 6.401 M1.7*0.2 1.45 1.500 1.460M36*1.534.5034.67634.376 3/8 - 168.008.1537.798 M3*0.5 2.63 - 2.60M1.8*0.2 1.60 1.621 1.583 7/16 - 149.409.5509.144M3.0*0.6 2.56 - 2.50M2.0*0.25 1.75 1.785 1.729 1/2 - 1310.8011.02310.592M3.5*0.6 3.06 - 3.03M2.2*0.25 1.95 1.985 1.929 9/16 - 1212.2012.44611.989使用绞刀时不使用绞刀时M4.0*0.7 3.49 - 3.45M2.3*0.25 2.05 2.610 2.001 5/8 - 1113.6012.86813.386PT 1/16 - 28 6.10 6.20 6.244 6.384 M4.0*0.75 3.45 - 3.41M2.5*0.35 2.20 2.221 2.121最大最小 3/4 - 1016.5018.84016.307PT 1/8 - 288.108.208.2498.388 M4.5*.75 3.96 - 3.92M2.6*0.35 2.20 2.246 2.186No 0-80(1.524) 1.25 1.305 1.182 7/8 - 919.5019.76119.177PT 1/4 - 1910.7011.0010.96211.174 M5.0*0.8 4.43 - 4.38M3.0*0.35 2.70 2.721 2.621No 1-72(1.854) 1.55 1.612 1.474 1 - 822.2022.60621.971PT 3/8 - 1914.2014.5014.44814.658 M5.0*0.9 4.36 - 4.31M3.5*0.35 3.20 3.221 3.121No 2-64(2.184) 1.85 1.912 1.756 1-1/8 - 725.0025.34924.638PT 1/2 - 1417.6018.0017.97918.263 M6.0*1.0 5.30 - 5.25M4.0*0.5 3.50 3.599 3.459No 3-58(2.515) 2.10 2.197 2.025 1-1/4 - 728.2028.52427.813PT 3/4 - 1423.0023.5023.37823.663 M7.0*1.0 6.30 - 6.25M4.5*0.5 4.00 4.099 3.959No 4-48(2.845) 2.40 2.458 2.271 1-3/8 - 630.8031.11530.353PT 1 - 1129.0029.5029.45929.822 M8.0*1.07.28 - 7.23M5.0*0.5 4.50 4.599 4.459No 5-44(3.175) 2.70 2.740 2.551 1-1/2 - 634.0034.29033.528PT 1-1/4 - 1137.5038.0037.97638.339 M8.0*1.257.12 - 7.07M5.5*0.5 5.00 5.099 4.959No 6-40(3.506) 2.90 3.022 2.820 1-3/4 - 539.5039.82738.964PT 1-1/2 - 1143.4044.0043.86944.232 M6.0*0.75 5.30 5.378 5.188No 8-36(4.166) 3.50 3.606 3.404 2 - 4-1/245.2045.59344.679PT 2 - 1154.9055.5055.41255.844 M6.0*0.5 5.50 5.550 5.400No 10-32(4.826) 4.10 4.165 3.963 M7.0*0.75 6.30 6.378 6.188No 12-28(5.846) 4.60 4.724 4.496 M7.0*0.5 6.50 6.550 6.4001/4 - 28 5.50 5.588 5.360M8.0*1.07.007.153 6.9175/16 - 24 6.907.035 6.782 M8.0*0.757.307.3787.1883/8 - 248.508.6368.382最大最小M8.0*0.57.507.5207.4007/16 - 209.9010.0339.729No 12 - 32 4.700 4.826 4.623使用绞刀时不使用绞刀时2BA 4.0 - 4.2M9.0*1.08.008.1537.9171/2 - 2011.5011.60711.3291/4 - 32 5.600 5.690 5.4861/16 - 27 6.10 6.25 6.35 3BA M9.0*0.758.308.3788.1889/16 - 1812.9013.08112.7515/16 - 327.1007.2647.0871/8 - 278.338.438.74 4BA 3.0 - 3.2M10*1.258.808.9128.6475/8 - 1814.5014.68114.3513/8 - 328.7008.8658.6611/4 -1810.7211.1311.13 5BA 2.7 - 2.8M10*1.09.009.1538.9173/4 - 1617.5017.67817.3237/16 - 2810.20010.33810.1353/8 -1814.2714.2714.68 6BA 2.4 - 2.5M10*0.759.309.3789.1887/8 - 1420.5020.57520.2701/2 - 2811.80011.93811.7091/2 -1417.4817.8618.26 M10*0.59.509.5209.400 1 - 1223.2023.57123.1149/16 - 2413.20013.38613.1323/4 -1422.6323.0123.42 M11*1.010.0010.1538.9171-1/8 - 1226.5026.74626.2895/8 - 2414.80014.98614.732 1 -11-1/228.5828.9829.36 M11*0.7510.3010.37810.1881-1/4 - 1229.5029.92129.4643/4 - 2017.80017.95817.6781-1/4-11-1/237.3137.6938.10 M12*1.5010.5010.67610.3761-3/8 - 1232.8033.09632.6397/8 - 2021.00021.13320.8531-1/2-11-1/243.6644.0444.45 M12*1.2510.8010.91210.6471-1/2 - 1236.0036.27135.814 1 - 2024.00024.30824.028 2 -11-1/255.5855.9656.36规格钻孔径规格滚造径英制电器螺纹公制螺纹规格滚造径2级牙钻孔径NPT 英 制 管 螺 纹 英 制 管 螺 纹 规格标准径有效牙部之长度（最小）中之毋螺牙内径标准长度（最小）中 之毋螺牙内径 规格(UNC)标准径规格标准率规格(UNF)标准径2级牙钻孔径规格2级牙钻孔径规格(UNC)标准径2级牙钻孔径注:迫牙丝攻之钻孔径,在上表所列之数值,由于被加工材料之材质,硬度,形状,尺寸等之影响,多少会有所变动,因此于参考上表之同时,亦精增减若干。 规格2级牙钻孔径公 制 粗 螺 纹公 制 细 螺 纹规格精 度 等 级标准径2级牙钻孔径 规格标准径美 制 粗 螺 纹美制迫牙丝攻钻孔径 规格NPS 规格英 制 管 螺 纹 钻孔径 精 度 等 级 标准径公制迫牙丝攻钻孔径美 制 特 细 螺 纹钻孔径螺丝攻牙钻孔径和滚造径对照表钻孔径 公 制 细 螺 纹美 制 细 螺 纹英 制 螺 纹针车用螺纹规格

非常全的攻丝钻孔直径表

螺纹底孔直径 一、螺纹底孔直径计算式 螺纹底孔直径可参照表1、表2的公式计算，也可查表3至表11。 表1 加工米制普通螺纹底孔钻头直径D的计算公式 适用范围 1 D = d – t 式中 d：螺纹的公称直径 t：螺距 （1）螺距t<1； （2）工件材料塑性较大； （3）孔扩张量适中。 2 D = d – (1.04～1.08)t （1）螺距t<1； （2）工件材料塑性较小；（3）孔扩张量较小。 表2 加工英制螺纹底孔钻头直径的计算公式 (mm) 螺纹公称直径 (英寸) 铸铁与青铜 钢与黄铜 3/16"～5/8" D = 25.4·(d - 1/n) D = 25.4·(d - 1/n) + 0.1 3/4"～1 1/2" D = 25.4·(d - 1/n) D = 25.4·(d - 1/n) + 0.2注：n—每英寸牙数

·2· 二、螺纹底孔直径表 表3 米制粗牙螺纹攻丝前用的钻头直径(mm) 螺 纹 小 直 径 级 别 公称直径 螺距5H max 6H max 7H max 5H、6H、7H min 钻头 直径 1 1. 2 1.6 2 2.5 3 4 5 6 8 10 12 14 16 18 20 22 24 0.25 0.25 0.35 0.4 0.45 0.5 0.7 0.8 1 1.25 1.5 1.75 2 2 2.5 2.5 2.5 3 0.785 0.985 1.301 1.657 2.112 2.571 3.382 4.294 5.007 6.859 8.612 10.371 12.135 14.135 15.649 17.649 19.649 21.152 1.321 1.679 2.138 2.599 3.422 4.334 5.153 6.912 8.676 10.441 12.210 14.210 15.744 17.744 19.744 21.252 2.639 3.466 4.384 5.217 6.982 8.751 10.531 12.310 14.310 15.854 17.854 19.854 21.382 0.729 0.929 1.221 1.561 2.013 2.459 3.242 4.134 4.917 6.647 8.376 10.106 11.835 13.835 15.294 17.294 19.294 20.754 0.75 0.95 1.25 1.60 2.05 2.50 3.30 4.20 5.00 6.80 8.50 10.2 12.0 14.0 15.5 17.5 19.5 21.0

丝锥和钻头的参数对照表

丝锥和钻头的参数对照表公制粗牙螺紋 JIS B 0209-1982(單位：mm) 螺纹尺寸钻头直 徑崁合度區分：中2級 下孔徑 崁合度區分：中2級 內螺紋小徑 最小直徑最大直徑 M 1 × 0.250.75 0.78 (80%) 0.729 0.785 1.1 × 0.250.85 0.88 (80%) 0.829 0.885 1.2 × 0.250.95 0.98 (80%) 0.929 0.985 1.4 × 0.3 1.1 1.14 (80%) 1.075 1.142 1.6 × 0.35 1.25 1.32 (75%) 1.221 1.321 1.8 × 0.35 1.45 1.52 (75%) 1.421 1.521 2 × 0.4 1.6 1.65 (80%) 1.567 1.679 2.2 × 0.45 1.75 1.8 3 (75%) 1.713 1.838 2.5 × 0.45 2.1 2.13 (75%) 2.013 2.138 3 × 0.5 2.5 2.59 (75%) 2.459 2.599 3.5 × 0.6 2.9 3.01 (75%) 2.850 3.010 4 × 0.7 3.3 3.39 (80%) 3.242 3.422 4.5 × 0.75 3.8 3.85 (80%) 3.688 3.878 5 × 0.8 4.2 4.31 (80%) 4.134 4.334 6 × 1 5 5.13 (80%) 4.91 7 5.153 7 × 1 6 6.13 (80%) 5.917 6.153 8 × 1.25 6.8 6.85 (85%) 6.647 6.912 9 × 1.257.8 7.85 (85%) 7.647 7.912 10 × 1.58.5 8.62 (85%) 8.376 8.676 11 × 1.59.5 9.62 (85%) 9.376 9.676 12 × 1.7510.3 10.40 (85%) 10.106 10.441 14 × 212 12.2 (85%) 11.835 12.210 16 × 214 14.2 (85%) 13.835 14.210 18 × 2.515.5 15.7 (85%) 15.294 15.744 20 × 2.517.5 17.7 (85%) 17.294 17.744 22 × 2.519.5 19.2 (85%) 19.294 19.744 24 × 321 21.2 (85%) 20.752 21.252 27 × 324 24.2 (85%) 23.752 24.252 30 × 3.526.5 26.6 (90%) 26.211 26.771 33 × 3.529.5 29.6 (90%) 29.211 29.771 36 × 432 32.1 (90%) 31.670 32.270 39 × 435 35.1 (90%) 34.670 35.270 42 × 4.537.5 37.6 (90%) 37.129 37.799 45 × 4.540.5 40.6 (90%) 40.129 40.799 48 × 543 43.1 (90%) 42.587 43.297

攻牙下孔径对照表

建議下孔徑Recommended Tap Drill Sizes ◎公製牙

● ● D1：Minor diameter of JIS Class 2 internal thread. But, the minor diameters D1 shown in ( ) are of JIS Class I internal threads because their nominal sizes are not specified in JIS Class 2. ● * Marked sizes have been eliminated from JIS since 1969. ◎公製牙

● The reccommended tap drill sizes indicated above are for JIS Class 2 Metric threads. ● D1：Minor diameter of JIS Class 2 internal thread. But, the minor diameters D1 shown in ( ) are of JIS Class I internal threads because their nominal sizes are not specified in JIS Class 2. ◎美製牙─ UNC，UNF

● The recommended tap drill sizes indicated above are for JIS Class 2B UNC & UNF threads, and ANSI BI . Ia Class 2B UNEF & UN threads. ● D1：Minor diameter of internal thread. For UNC and UNF threads, according to JIS Class 2B; For UNEF and UN threads, according to ANSI BI . Ia, Class 2B. ◎英製牙─ BSW ● The recommended tap drill sizes indicated above are for JIS Class 2 Whitworth threads. ● Generally, the tap drill sizes in column A are used for producing holes; When holes tend to be cut oversized, the tap drill sizes in column B should be selected. ● These tap drill sizes are in accordance with JIS B 1004-1966, while the nominal sizes with a * mark are in accordance with BSW (Please refer to page 135).

螺丝攻牙孔径对照表

螺丝攻牙钻孔径对照表 美制（粗）挤牙丝攻钻孔径 公制挤牙丝攻钻孔径 美制细牙螺纹 公制细牙螺纹 规格精度max min 规格精度max min 2-56UNC RH4 2.02 1.96M1.0 0.25RH40.920.90最大最小最大最小3-48RH4 2.32 2.25M1.1 0.25RH4 1.02 1.00螺丝牙外径 M7.0 0.50 6.50 6.550 6.4004-40RH5 2.60 2.52M1.2 0.25RH4 1.12 1.10No.0-80（1.524） 1.25 1.305 1.182M8.0 1.00 7.007.153 6.9175-40RH5 2.93 2.86M1.4 0.30RH4 1.294 1.270No.1-72（1.854） 1.55 1.612 1.474M 8.0 0.757.307.3787.1886-32RH5 3.17 3.09M1.6 0.35RH4 1.45 1.40No.2-64（2.184） 1.85 1.912 1.756M8.0 0.507.507.5207.4008-32RH6 3.83 3.75M1.7 0.35RH4 1.58 1.54No.3-56（2.515） 2.10 2.197 2.025M 9.0 1.008.008.1537.91710-24RH6 4.35 4.26M2.0 0.40RH4 1.85 1.81No.4-48（2.845） 2.40 2.458 2.271M9.0 0.758.308.3788.18812-24RH6 5.01 4.92M2.3 0.40RH4 2.15 2.11No.5-44（3.175） 2.70 2.740 2.551M10.0 1.258.808.9128.6471/4-20RH6 5.76 5.66M2.5 0.45RH4 2.33 2.28No.6-40（3.505） 2.90 3.022 2.820M10.0 1.009.009.1538.9175/16-18RH77.297.18M2.6 0.45RH4 2.43 2.38No.8-36（4.166） 3.50 3.606 3.404M10.0 0.759.309.3789.1883/8-16RH78.788.66M3.0 0.50RH5 2.81 2.76No.10-32（4.826） 4.10 4.165 3.963M10.0 0.509.509.5209.4007/16-14RH710.2510.11M3.5 0.60RH5 3.26 3.20No.12-28（5.486） 4.60 4.724 4.496M11.0 1.0010.0010.1539.9171/2-13RH811.7811.62M4.0 0.70RH6 3.70 3.651/4-28 5.50 5.588 5.360M11.0 0.7510.3010.37810.1889/16-12RH1013.2713.14M5.0 0.80RH6 4.66 4.595/16-24 6.907.035 6.782M12.0 1.5010.5010.67610.3765/8-11RH1114.7614.62M6.0 1.00RH7 5.57 5.483/8-248.508.6368.382M12.0 1.2510.8010.91210.6473/4-10RH1217.8817.67M7.0 1.00RH7 6.57 6.487/16-209.9010.0339.729M12.0 1.0011.0011.15310.9177/8-9RH1220.8520.68M8.0 1.00RH77.577.481/2-2011.5011.60711.329M12.0 0.5011.5011.52011.4001-8 RH13 23.84 23.65 M8.0 1.25RH77.417.349/16-1812.9013.08112.751M14.0 1.5012.5012.67612.376M10 1.00RH79.579.485/8-1814.5014.68114.351M14.0 1.0013.0013.15312.917美制（细）挤牙丝攻钻孔径 M10 1.25RH79.419.343/4-1617.5017.67817.323M15.0 1.5013.5013.67613.376规格精度max min M10 1.50RH79.289.187/8-1420.5020.67520.270M15.0 1.0014.0014.15313.9172-64UNF RH3 2.04 1.98M12 1.00RH711.5711.181-12 23.3023.57123.114M16.0 1.5014.5014.67614.3763-56RH4 2.35 2.29M12 1.25RH711.4111.051-1/8-1226.5026.74626.289M16.0 1.0015.0015.15314.9174-48RH4 2.64 2.57M12 1.50RH711.2811.481-1/4-1229.6029.92129.464M17.0 1.5015.5015.67615.3765-44RH4 2.95 2.88M12 1.75RH811.1511.341-3/8-1232.8033.09632.639M17.0 1.0016.0016.15315.9176-40RH5 3.26 3.19M14 1.50RH913.3013.211-1/2-12 36.00 36.271 35.814 M18.0 2.0016.0016.21015.8358-36RH5 3.88 3.80M14 2.00RH1013.0412.92M18.0 1.5016.5016.67616.37610-32RH5 4.48 4.41M16 1.50RH915.3015.21M18.0 1.0017.0017.15316.91712-28RH5 5.08 5.00M16 2.00RH1015.0414.92M20.0 2.0018.0018.21017.8351/4-28RH5 5.93 5.86M18 1.5RH1017.3117.22M20.0 1.5018.5018.67618.3765/16-24RH67.467.38M18 2.5RH1116.7816.63M20.0 1.0019.0019.15318.9173/8-24RH69.058.96M20 1.5RH1019.3119.22M22.0 2.0020.0020.21019.8357/16-20RH710.5410.44M20 2.5 RH11 18.78 18.63 M22.0 1.5020.5020.67620.3761/2-20RH712.1212.02M22.0 1.0021.0021.15320.9179/16-18RH913.6613.55最大最小M24.0 2.0022.0022.21021.8355/8-18RH915.2515.14螺丝牙外径 M24.0 1.5022.5022.67622.3763/4-16RH1018.3218.22 1. 外径-牙距?0.45=下孔＜D-P?0.45＞No.1-64（1.854） 1.55 1.582 1.425M24.0 1.0023.0023.15322.9177/8-14RH1121.3821.27 2. Dn=D-0.2P-0.00403?P?f1+0.0127?n No.2-56（2.184） 1.80 1.871 1.695M25.0 2.0023.0023.21022.8351-12RH12 24.4124.28 ＜例＞M3?0.5RH6 2级母螺纹攻牙 咬合率90%No.3-48（2.515） 2.10 2.146 1.941M25.0 1.5023.5023.67623.376Dn=3-0.2?0.5-0.00403?0.5?90+0.0127?6No.4-40（2.845） 2.30 2.385 2.157M25.0 1.0024.0024.15323.917 =2.80 No.5-40（3.175） 2.60 2.697 2.487M26.0 1.5024.5024.67624.376山数 山数 Dn=下孔径 D=基准外径 P=牙距No.6-32（3.505） 2.80 2.895 2.642M27.0 2.0025.0025.21024.835每25.4mm 每25.4mm f1=咬合率 n=RH 精度 No.8-32（4.166） 3.40 3.530 3.302M27.0 1.5025.5025.67625.3761000.254012 2.1167No.10-24（4.826） 3.90 3.962 3.683M27.0 1.0026.0026.15325.917800.317511 2.3091No.12-24（5.486） 4.50 4.597 4.344M28.0 2.0026.0026.21025.835720.352810 2.54001/4-20 5.10 5.257 4.979M28.0 1.5026.5026.67626.376640.39699 2.82225/16-18 6.60 6.731 6.401M28.0 1.0027.0027.15326.917600.42338 3.17503/8-168.008.1537.798M30.0 3.0027.0027.25226.752560.45367 3.62867/16-149.409.5509.144M30.0 2.0028.0028.21027.835480.52926 4.23331/2-1310.9011.02310.592M30.0 1.5028.5028.67628.376440.57735 5.0800规格吋 mm 9/16-1212.2012.46611.989M30.0 1.0029.0029.15328.917400.63504 1/2 5.6444 No. 0 0.0600 1.5245/8-1113.6013.86813.386M32.0 2.0030.0030.21029.835360.70564 6.350010.0730 1.8543/4-1016.6016.84016.307M32.0 1.5030.5030.67630.376320.79383 1/27.257120.0860 2.1847/8-919.6019.76119.177M33.0 3.0030.0030.25229.752280.90713 1/47.815430.0990 2.5151-8 22.3022.60621.971M33.0 2.0031.0031.21030.83524 1.058338.466740.1120 2.8451-1/8-725.0025.34924.638M33.0 1.5031.5031.67631.37620 1.27002 7/88.834850.1250 3.1751-1/4-728.2028.52427.813M35.0 1.5033.5033.67633.37618 1.41112 3/49.236460.1380 3.5051-3/8-630.8031.11530.353M36.0 3.0033.0033.25232.75216 1.58752 5/89.676280.1640 4.1661-1/2-634.0034.29033.528M36.0 2.0034.0034.21033.83514 1.81432 1/2 10.1600 100.1900 4.8261-3/4-539.5039.82738.964M36.0 1.50 34.50 34.67634.376 13 1.9538 12 0.2160 5.486 2-4-1/2 45.20 45.593 44.679 美制螺丝外径公厘（mm ）换算表 美制粗牙螺纹 规格标准径2级牙钻孔径NRT 下孔径计算式 2级牙钻孔径规格 标准径 2级牙钻孔径牙距mm 牙距mm 规格 标准径 山数节距换算表