丝锥用底孔钻头直径表
(螺纹牙型高度为75%时的推荐钻头尺寸)
| 准备攻丝的螺纹 | 钻头规格代码 | (最接近的英制分数规格) | 英制小数规格 |
| 0-80UNF | 3/64 | 3/64 | .0469 |
| 1-64UNC | #53 | - | .0595 |
| 1-72UNF | #53 | 1/16 | .0595 |
| 2-56UNC | #50 | - | .0700 |
| 2-64UNF | #50 | - | .0700 |
| 3-48UNC | #47 | 5/64 | .0785 |
| 3-56UNF | #45 | - | .0820 |
| 4-36UNS | #44 | - | .0860 |
| 4-40UNC | #43 | 3/32 | .0890 |
| 4-48UNF | #42 | 3/32 | .0935 |
| M3×0.60 | 2.5mm | - | .0984 |
| 1/8-40UNS | #38 | - | .1015 |
| 5-40UNC | #38 | - | .1015 |
| 5-44UNF | #37 | - | .1040 |
| 6-32UNC | #35 | 7/64 | .1100 |
| 6-36UNS | #34 | - | .1110 |
| 6-40UNF | #33 | - | .1130 |
| 6-48UNS | #31 | - | .1200 |
| M4×0.70 | 3.4mm | - | .1338 |
| M4×0.75 | 3.4mm | - | .1338 |
| 8-32UNC | #29 | - | .1360 |
| 8-36UNF | #29 | 9/64 | .1360 |
| 8-40UNS | #28 | - | .1405 |
| 3/16-24UNS | #26 | - | .1470 |
| 10-24UNC | #25 | 5/32 | .1495 |
| 3/16-32UNS | #22 | - | .1570 |
| 10-32UNF | #21 | 5/32 | .1590 |
| M5×0.90 | 4.2mm | - | .1653 |
| M5×0.80 | 4.3mm | - | .1693 |
| 12-24UNC | #16 | 11/64 | .1770 |
| 12-28UNF | #14 | 3/16 | .1820 |
| 12-32NEF | #13 | - | .1850 |
| 14-20UNS | #10 | - | .1935 |
| 1/4-20UNC | #7 | 13/64 | .2010 |
| 14-24UNS | #7 | - | .2010 |
| M6×1.00 | 5.2mm | - | .2047 |
| 1/4-24UNS | #4 | - | .2090 |
| 1/4-28UNF | #3 | 7/32 | .2130 |
| 1/4-32NEF | 7/32 | 7/32 | .2188 |
| 1/4-40UNS | #1 | - | .2280 |
| M7×1.00 | 6.1mm | 15/64 | .2401 |
| 5/16-18UNC | 字母F | 17/64 | .2570 |
| M8×1.25 | 6.9mm | 17/64 | .2716 |
| 5/16-24UNF | 字母I | - | .2720 |
| M8×1.00 | 7.1mm | - | .2795 |
| 5/16-32NEF | 9/32 | 9/32 | .2812 |
| M9×1.2 | 7.9mm | - | .3110 |
| 3/8-16UNC | 5/16 | 5/16 | .3125 |
| M9×0.75 | 8.3mm | - | .3268 |
| M9×1.00 | 8.1mm | - | .3189 |
*该螺纹仅用于火花塞
| 准备攻丝的螺纹 | 钻头规格代码 | (最接近的英制分数规格) | 英制小数规格 |
| 3/8-24UNF | 字母Q | 21/64 | .3320 |
| M10×1.50 | 8.7mm | - | .3425 |
| M10×1.25 | 8.9mm | 11/32 | .3503 |
| M10×1.00* | 9.1mm | - | .3583 |
| 7/16-14UNC | 字母U | 23/64 | .3680 |
| M11×1.50 | 9.7mm | - | .3818 |
| 7/16-20UNF | 25/64 | 25/64 | .3906 |
| M12×1.75 | 10.5mm | - | .4133 |
| M12×1.50 | 10.7mm | 27/64 | .4212 |
| 1/2-13UNC | 27/64 | 27/64 | .4219 |
| M12×1.25* | 10.9mm | 27/64 | .4291 |
| 1/2-20UNF | 29/64 | 29/64 | .4531 |
| 1/2-24UNS | 29/64 | 29/64 | .4531 |
| M14×2.00 | 12.2mm | - | .4803 |
| 9/16-12UNC | 31/64 | 31/64 | .4844 |
| M14×1.50 | 12.7mm | - | .4999 |
| M14×1.25* | 12.8mm | - | .5039 |
| 9/16-18UNF | 33/64 | 33/64 | .5156 |
| 5/8-11UNC | 17/32 | 17/32 | .5312 |
| M16×2.00 | 14.2mm | 35/64 | .5590 |
| 5/8-18UNF | 37/64 | 37/64 | .5781 |
| M16×1.50 | 14.7mm | - | .5787 |
| 11/16-11UNS | 19/32 | 19/32 | .5938 |
| M18×2.50 | 15.8mm | 39/64 | .5220 |
| 11/16-16UNS | 5/8 | 5/8 | .6250 |
| 3/4-10UNC | 21/32 | 21/32 | .6562 |
| M18×1.50* | 16.8mm | - | .6614 |
| 3/4-16UNF | 11/16 | 11/16 | .6875 |
| M20×2.50 | 17.8mm | 11/16 | .7008 |
| 7/8-9UNC | 49/64 | 49/64 | .7656 |
| 7/8-14UNF | 13/16 | 13/16 | .8125 |
| M22×1.50 | 20.9mm | - | .8228 |
| 7/8-18UNS* | 53/64 | 53/64 | .8281 |
| M24×3.00 | 21.4mm | 53/64 | .8425 |
| 1-8UNC | 7/8 | 7/8 | .8750 |
| M24×2.00 | 22.3mm | - | .8779 |
| 1-12UNF | 59/64 | 59/64 | .9219 |
| 1-14UNS | 15/16 | 15/16 | .9375 |
| 11/8-7 UNC | 63/64 | 63/64 | .9844 |
| 11/8-12 UNF | 13/64 | 13/64 | 1.0469 |
| 11/4-7 UNC | 17/64 | 17/64 | 1.1094 |
| 11/4-12 UNF | 111/64 | 111/64 | 1.1719 |
| 13/8-6 UNC | 17/32 | 17/32 | 1.2188 |
| 13/8-12 UNF | 119/64 | 119/64 | 1.2969 |
| 11/2-6 UNC | 111/32 | 111/32 | 1.3438 |
| 11/2-12 UNF | 127/64 | 127/64 | 1.4219 |
NPT螺纹底孔表
(螺纹牙型高度为75%时的推荐钻头尺寸)
| 准备攻丝的螺纹 | 钻头规格代码 | (最接近的英制分数规格) | 英制小数规格 |
| 1/8-27NPT | 字母R | - | .3390 |
| 1/4-18NPT | 7/16 | 7/16 | .4375 |
| 3/8-18NPT | 37/64 | 37/64 | .5781 |
| 1/2-14NPT | 45/64 | 45/64 | .7031 |
| 3/4-14NPT | 59/64 | 59/64 | .9219 |
| 1-11½ NPT | 15/32 | 15/32 | 1.1562 |
| 1¼-11 ½ NPT | 1½ | 1½ | 1.5000 |
| 1½-11 ½ NPT | 147/64 | 147/64 | 1.7344 |
| 2-11½ NPT | 27/32 | 27/32 | 2.2188 |
