丝锥用底孔钻头的直径表.doc

丝锥用底孔钻头的直径表 (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 M30.60 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 M40.70 3.4mm - .1338 M40.75 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 M50.90 4.2mm - .1653 M50.80 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 M61.00 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 M71.00 6.1mm 15/64 .2401 5/16-18UNC 字母F 17/64 .2570 M81.25 6.9mm 17/64 .2716 5/16-24UNF 字母I - .2720 M81.00 7.1mm - .2795 5/16-32NEF 9/32 9/32 .2812 M91.2 7.9mm - .3110 3/8-16UNC 5/16 5/16 .3125 M90.75 8.3mm - .3268 M91.00 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 M101.50 8.7mm - .3425 M101.25 8.9mm 11/32 .3503 M101.00* 9.1mm - .3583 7/16-14UNC 字母U 23/64 .3680 M111.50 9.7mm - .3818 7/16-20UNF 25/64 25/64 .3906 M121.75 10.5mm - .4133 M121.50 10.7mm 27/64 .4212 1/2-13UNC 27/64 27/64 .4219 M121.25* 10.9mm 27/64 .4291 1/2-20UNF 29/64 29/64 .4531 1/2-24UNS 29/64 29/64 .4531 M142.00 12.2mm - .4803 9/16-12UNC 31/64 31/64 .4844 M141.50 12.7mm - .4999 M141.25* 12.8mm - .5039 9/16-18UNF 33/64 33/64 .5156 5/8-11UNC 17/32 17/32 .5312 M162.00 14.2mm 35/64 .5590 5/8-18UNF 37/64 37/64 .5781 M161.50 14.7mm - .5787 11/16-11UNS 19/32 19/32 .5938 M182.50 15.8mm 39/64 .5220 11/16-16UNS 5/8 5/8 .6250 3/4-10UNC 21/32 21/32 .6562 M181.50* 16.8mm - .6614 3/4-16UNF 11/16 11/16 .6875 M202.50 17.8mm 11/16 .7008 7/8-9UNC 49/64 49/64 .7656 7/8-14UNF 13/16 13/16 .8125 M221.50 20.9mm - .8228 7/8-18UNS* 53/64 53/64 .8281 M243.00 21.4mm 53/64 .8425 1-8UNC 7/8 7/8 .8750 M242.00 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 .