美制螺纹底孔直径表.docx

6.230
6.2
6.490
6.5
－
－
1/8‐28
8.235
8.2
8.495
8.5
8.191
8.2
1/4‐19
10.941
10.9
11.341
11.4
10.945
10.9
3/8‐19
14.428
14.4
14.846
14.9
14.388
14.4
1/2‐14
17.950
18
18.489
18.5
17.943
14
20
14
18
1/2”
12.70
13
18
12
16
9/16”
14.29
12
18
12
16
5/8”
15.88
11
/
11
14
11/16”
17.46
/
16
11
14
3/4”
19.05
10
/
10
12
13/16”
20.64
/
14
/
/
7/8”
22.23
9
/
9
11
15/16”
23.81
/
12
/
/
1”
25.40
8
12
8
t＞1毫米，dz=d-（1.04～1.06)t
式中t——螺距（毫米）
dz——攻丝前钻孔直径（毫米）
d——螺纹公称直径（毫米）
2.攻英制螺纹：
螺纹公称直径铸铁与青铜钢与黄铜
3/16"～5/8" dz＝25（d-1/n) dz＝25（d-1/n)+0.1

螺纹小径螺纹外径MaxMin Max Min Max Min Max Min Max Min 1-64UNC640.2360.3972A 1.83896 1.74244 1.58242 1.53162 1.366522B 1.42494 1.58242 1.59766 1.6637 1.8542 1.3973A1.8542 1.75768 1.59766 1.55956 1.381763B 1.42494 1.58242 1.59766 1.64592 1.8542 1.3971-72UNF720.210.3532A 1.83896 1.75006 1.61036 1.5621 1.419862B 1.4732 1.6129 1.6256 1.6891 1.8542 1.51133A1.8542 1.7653 1.6256 1.59004 1.43513B 1.4732 1.6129 1.6256 1.67386 1.8542 1.51132-56UNC560.2710.4542A 2.16916 2.06502 1.87452 1.82118 1.630682B 1.69418 1.87198 1.88976 1.96088 2.1844 1.70183A2.1844 2.08026 1.88976 1.84912 1.645923B 1.69418 1.87198 1.88976 1.9431 2.1844 1.70182-64UNF640.2360.3972A 2.16916 2.07264 1.91262 1.86182 1.696722B 1.75514 1.91262 1.92786 1.99644 2.1844 1.7783A2.1844 2.08788 1.92786 1.88976 1.711963B 1.75514 1.91262 1.92786 1.97866 2.1844 1.7783-48UNC480.3150.5292A 2.49682 2.38252 2.15392 2.0955 1.864362B 1.94056 2.1463 2.1717 2.2479 2.5146 1.99393A2.5146 2.4003 2.1717 2.12852 1.882143B 1.94056 2.1463 2.1717 2.22758 2.5146 1.99393-56UNF560.2710.4542A 2.49682 2.39268 2.20218 2.1463 1.958342B 2.02438 2.1971 2.21996 2.29108 2.5146 2.05743A2.5146 2.41046 2.21996 2.17932 1.976123B 2.02438 2.1971 2.21996 2.2733 2.5146 2.05744-40UNC400.3780.6352A 2.82448 2.69494 2.413 2.3495 2.067562B 2.15646 2.38506 2.43332 2.51714 2.8448 2.18443A2.8448 2.71526 2.43332 2.38506 2.087883B 2.15646 2.38506 2.43332 2.49428 2.8448 2.18444-48UNF480.3150.5292A 2.82702 2.71272 2.48412 2.42316 2.194562B 2.27076 2.45872 2.5019 2.58064 2.8448 2.26063A2.8448 2.7305 2.5019 2.45618 2.212343B 2.27076 2.45872 2.5019 2.56032 2.8448 2.26065-40UNC400.3780.6352A 3.15468 3.02514 2.7432 2.67716 2.397762B 2.48666 2.69748 2.76352 2.84734 3.175 2.52733A3.175 3.04546 2.76352 2.71526 2.418083B 2.48666 2.69748 2.76352 2.82702 3.175 2.52735-44UNF440.3440.5772A 3.15722 3.0353 2.7813 2.7178 2.468882B 2.55016 2.74066 2.79908 2.88036 3.175 2.57813A3.175 3.05308 2.79908 2.75082 2.486663B 2.55016 2.74066 2.54508 2.86004 3.175 2.57816-32UNC320.4720.7942A 3.48488 3.33248 2.96926 2.89814 2.542B 2.6416 2.8956 2.98958 3.08356 3.5052 2.70513A3.5052 3.3528 2.98958 2.93624 2.560323B 2.6416 2.8956 2.98958 3.05816 3.5052 2.70516-40UNF400.3780.6352A 3.48488 3.35534 3.0734 3.00736 2.727962B 2.8194 3.0226 3.09372 3.18008 3.5052 2.87023A3.50523.375663.093723.042922.748283B2.81943.012443.093723.157223.50522.8702公称直径螺纹规格牙数牙高螺距公差代号螺纹外径钻孔直径0.073（#1）1.8540.086(#2)2.1840.099(3#)2.515螺纹中经公差代号螺纹小径螺纹中径0.112(#4)2.8450.125(#5)3.1750.138(#6）3.505螺纹小径螺纹外径MaxMin Max Min Max Min Max Min Max Min 公称直径螺纹规格牙数牙高螺距公差代号螺纹外径钻孔直径螺纹中经公差代号螺纹小径螺纹中径8-32UNC320.4720.7842A 4.14274 3.99034 3.62712 3.55346 3.197862B 3.302 3.5306 3.64998 3.7465 4.1656 3.45443A4.1656 4.0132 3.64998 3.5941 3.220723B 3.302 3.52806 3.64998 3.7211 4.1656 3.45448-36UNF360.4210.7062A 4.14528 4.00558 3.68808 3.61696 3.304542B 3.4036 3.6068 3.7084 3.79984 4.1656 3.45443A4.1656 4.0259 3.7084 3.65506 3.324863B 3.4036 3.59664 3.7084 3.77698 4.1656 3.454410-24UNC240.631.0582A 4.8006 4.61772 4.11226 4.02844 3.540762B 3.683 3.9624 4.13766 4.24688 4.826 3.73383A4.826 4.64312 4.13766 4.07416 3.566163B 3.683 3.9497 4.13766 4.21894 4.826 3.733810-28UNS 280.540.9072A 4.8006 4.6355 4.21132 4.1275 3.718562B 3.8354 4.064 4.23672 4.34594 4.826 3.860810-32UNF320.4720.7842A 4.80314 4.65074 4.28752 4.21132 3.858262B 3.9624 4.1656 4.31038 4.40944 4.826 3.98783A 4.826 4.6736 4.31038 4.25196 3.881123B 3.9624 4.16814 4.31038 4.38404 4.826 3.987810-36UNS 360.4210.7062A 4.80314 4.66344 4.34594 4.26974 3.96242B 4.064 4.2164 4.3688 4.46786 4.826 4.038610-40UNS 400.3780.6352A 4.80314 4.6736 4.39166 4.318 4.043682B 4.1402 4.2926 4.41452 4.5085 4.826 4.089410-48UNS 480.3150.5292A 4.80568 4.69138 4.46278 4.39674 4.175762B 4.2418 4.3688 4.4831 4.56946 4.826 4.216410-56UNS 560.2710.4542A 4.80822 4.70408 4.51358 4.45008 4.269742B 4.3434 4.445 4.53136 4.61264 4.826 4.305312-24UNC240.631.0582A 5.461 5.27812 4.77266 4.6863 4.201162B 4.3434 4.5974 4.79806 4.90982 5.4864 4.49583A5.4864 5.30352 4.79806 4.73202 4.226563B 4.3434 4.58978 4.79806 4.88188 5.4864 4.495812-28UNF280.540.9072A 5.461 5.2959 4.87172 4.79044 4.378962B 4.4958 4.7244 4.89712 5.0038 5.4864 4.5723A5.4864 5.3213 4.89712 4.83616 4.404363B 4.4958 4.71678 4.89712 4.97586 5.4864 4.57212-32UNEF320.4720.7842A 5.46354 5.31114 4.94792 4.86918 4.518662B 4.6228 4.826 4.97078 5.07492 5.4864 4.5723A5.4864 5.334 4.97078 4.90982 4.541523B 4.6228 4.8133 4.97078 5.04952 5.4864 4.57212-36UNS 360.4210.7062A 5.46354 5.32384 5.00634 4.93014 4.879342B 4.7244 4.8768 5.0292 5.12826 5.4864 4.800612-40UNS 400.3780.6352A 5.46354 5.334 5.05206 4.9784 4.66092B 4.8006 4.953 5.07492 5.1689 5.4864 4.851412-48UNS 480.3150.5292A 5.46608 5.35178 5.12318 5.05714 4.836162B 4.9022 5.0292 5.1435 5.22986 5.4864 4.978412-56UNS560.2710.4542A5.468625.364485.173985.110484.930142B5.00385.10545.191765.273045.48644.97840.164（#8）4.1660.19（#10）4.8260.216（#12）0.486螺纹小径螺纹外径MaxMin Max Min Max Min Max Min Max Min 公称直径螺纹规格牙数牙高螺距公差代号螺纹外径钻孔直径螺纹中经公差代号螺纹小径螺纹中径1/4-20UNC200.7561.271A 6.32206 6.01218 5.49656 5.35432 4.810761B 4.9784 5.2578 5.5245 5.70992 6.35 5.10542A 6.32206 6.11632 5.49656 5.40258 4.810762B 4.9784 5.2578 5.5245 5.64896 6.35 5.10543A6.35 6.14426 5.5245 5.45338 4.83873B 4.9784 5.25018 5.5245 5.61594 6.35 5.10541/4-24UNS 240.63 1.0582A 6.32206 6.13918 5.63372 5.53974 5.062222B 5.207 5.461 5.66166 5.78358 6.35 5.30861/4-27UNS 270.560.9412A 6.3246 6.15442 5.71246 5.62356 5.204462B 5.334 5.5626 5.73786 5.85216 6.35 5.41021/4-28UNF280.540.9071A 6.3246 6.07568 5.73532 5.60832 5.242561B 5.3594 5.588 5.76072 5.92582 6.35 5.41022A 6.3246 6.1595 5.73532 5.6515 5.242562B 5.3594 5.588 6.82752 5.86994 6.35 5.41023A 6.35 6.1849 5.76072 5.69722 5.267963B 5.3594 5.5626 6.82752 5.842 6.35 5.41021/4-32UNEF320.4720.7842A 6.3246 6.1722 5.80898 5.7277 5.379722B 5.4864 5.6896 5.83438 5.94106 6.35 5.554983A6.35 5.6896 5.83438 5.77342 5.405123B 5.4864 5.66166 5.83438 5.91312 6.35 5.554981/4-36UNS 360.4210.7062A 6.32714 6.18744 5.86994 5.7912 5.488942B 5.588 5.7404 5.8928 5.9944 6.35 5.61341/4-40UNS 400.3780.6352A 6.32714 6.1976 5.91566 5.842 5.570222B 5.6642 5.8166 5.93852 6.03504 6.35 5.79121/4-48UNS 480.3150.5292A 6.32968 6.21538 5.98678 5.9182 5.697222B 5.7658 5.8928 6.0071 6.09854 6.35 5.79121/4-56UNS 560.2710.5452A 6.32968 6.22554 6.03504 5.969 5.79122B 5.8674 5.969 6.05536 6.13918 6.35 5.94365/16-18UNC180.8411.4111A 7.907027.57428 6.99008 6.83514 6.228081B 6.4008 6.7317.020567.221227.9375 6.52782A 7.907027.68604 6.99008 6.88848 6.228082B 6.4008 6.7317.020567.155187.9375 6.52783A7.93757.716527.02056 6.94436 6.258563B 6.4008 6.68027.020567.119627.9375 6.52785/16-20UN200.7561.272A 7.907027.701287.08152 6.97992 6.395722B 6.5532 6.8587.1127.244087.9375 6.746243A7.93757.731767.1127.0358 6.42623B 6.5532 6.80727.1127.211067.9375 6.746245/16-24240.631.0581A 79095.67.635247.221227.08152 6.649721B 6.78187.03587.249167.42957.9375 6.90882A7.909567.726687.221227.12724 6.649722B 6.78187.03587.249167.371087.9375 6.90883A7.93757.754627.249167.18058 6.677663B 6.7818 6.995167.249167.34067.9375 6.90885/8-27UNS 270.560.9412A 7.91217.741927.299967.21106 6.791962B 6.90887.13747.249167.439667.93757.03585/8-28UN280.540.9072A7.91217.7477.322827.236466.830062B6.95967.16287.348227.459987.93757.03580.25"6.350.3125"7.9375螺纹小径螺纹外径MaxMin Max Min Max Min Max Min Max Min 公称直径螺纹规格牙数牙高螺距公差代号螺纹外径钻孔直径螺纹中经公差代号螺纹小径螺纹中径3A7.93757.77247.348227.28218 6.855463B 6.95967.129787.348227.432047.93757.03585/8-32UNEF320.4720.7842A 7.91217.75977.31527.3152 6.967222B 7.08667.26447.421887.528567.93757.142483A7.93757.78517.360927.36092 6.992623B 7.08667.231387.421887.500627.93757.142485/8-36UNS 360.4210.7062A 7.914647.774947.45744 5.32137.07392B 7.16287.34067.48037.58197.93757.142485/8-40UNS 400.3780.6352A 7.914647.78517.503167.42957.157722B 7.2397.39147.526027.622547.93757.3665/8-48UNS 40.3120.3150.5292A 7.917187.802887.574287.50577.287262B 7.3667.4937.59467.686047.93757.3663/8-16UNC180.8411.4111A 9.491989.13138.460748.295647.599681B 7.79788.15348.493768.709669.5257.93752A 9.491989.253228.460748.348987.599682B 7.79788.15348.493768.638549.5257.93753A9.5259.286248.493768.409947.63273B 7.79788.082288.493768.602989.5257.93753/8-18UNS 180.841 1.4112A 9.491989.2718.575048.465827.813042B 8.0018.33128.608068.75039.5258.02643/8-20UN200.7561.272A 9.494529.288788.669028.564887.983222B 8.15348.43288.69958.836669.5258.333743A9.5259.319268.69958.620768.01373B 8.15348.374388.69958.69959.5258.333743/8-24UNF240.631.0581A 9.497069.222748.808728.663948.237221B 8.3828.6368.836668.836669.5258.43282A 9.497069.314188.808728.71228.237222B 8.3828.6368.836668.961129.5258.43283A 9.5259.342128.836668.7638.265163B 8.3829.44888.836668.5130649.5258.43283/8-27UNS 270.560.9412A 9.497069.326888.884928.793488.376922B 8.5098.73768.912869.032249.5258.61063/8-28UN280.540.9072A 9.497069.331968.907788.816348.415022B 8.53448.7638.935729.052569.5258.61063A9.5259.35998.935728.867148.442963B 8.53448.702048.935729.024629.5258.61063/8-32UNEF320.4720.7842A 8.569969.34728.983988.897628.554722B 8.66148.86469.009389.121149.5258.83923A9.5259.37269.009388.945888.580123B 8.66148.811269.009389.09329.5258.83923/8-36UNS 360.4210.7062A 9.49969.35999.04248.961128.658862B 8.7638.94089.06789.174489.5258.83923/8-40UNC400.3780.6352A 9.502149.37269.090669.011928.745222B 8.83928.99169.113529.215129.5258.83920.39" 9.9060.390-27UNS270.560.9412A9.878069.707889.265929.174488.757922B8.899.11869.293869.413249.9068.83920.325"8.255螺纹小径螺纹外径MaxMinMax Min Max Min Max Min Max Min 公称直径螺纹规格牙数牙高螺距公差代号螺纹外径钻孔直径螺纹中经公差代号螺纹小径螺纹中径7/16-14UNC141.0811.8141A 11.0769410.683249.898389.718048.917941B 9.1449.55049.9339410.1676211.11259.34722A 11.0769410.815329.898389.7798.917942B 9.1449.55049.9339410.0888811.11259.34723A11.112510.850889.933949.845048.95353B 9.1449.441189.9339410.0507811.11259.34727/16-16UNS160.861.5882A 11.0769410.8381810.04579.928869.184642B 9.3989.753610.0812610.2311211.11259.57583A11.0667810.8737410.081269.99499.22023B 9.3989.65210.0812610.1955611.11259.57587/16-18UNS 180.841 1.4112A 11.0794810.858510.1625410.053329.400542B 9.57589.90610.1955610.337811.11259.80447/16-20UNF200.7561.271A 11.0794810.769610.9397810.09659.568181B 9.728210.03310.28710.4927411.066789.921242A 11.0794810.8737410.9397810.14739.568182B 9.728210.03310.28710.4241611.066789.921243A11.112510.9067610.312410.208269.60123B 9.72829.9466410.28710.3911411.066789.921247/16-24UNS 240.63 1.0582A 11.0845610.9016810.3962210.29979.824722B 9.956810.210810.4241610.5486211.0667810.08387/16-27UNS 270.560.9412A 11.0845610.9143810.4724210.380989.964422B 10.083810.312410.5003610.6197411.112510.26167/16-28UNEF280.540.9072A 11.0845610.9194610.4952810.4038410.002522B 10.134610.337810.5232210.6400611.112510.26163A11.112510.94748.67232210.4546410.030463B 10.134611.4579410.5232210.6121211.112510.26167/16-32UN320.4720.7842A 11.087110.934710.5714810.4851210.142222B 10.261610.439410.5968810.7086411.112510.26163A11.112510.960110.5968810.5333810.167623B 10.261610.3987610.5968810.680711.112510.26161/2-13UNC131.1631.9541A 12.661912.2478811.391911.2039410.259061B 10.591811.023611.4311.6763812.710.716262A 12.661912.3850411.391911.264910.335262B 10.591811.023611.4311.595112.710.716263A12.712.4231411.4311.3360210.373363B 10.591810.8813611.4311.5519212.710.716261/2-12UNS121.262.1172A 12.6593612.369811.2852211.1480610.139682B 10.41410.871211.3258611.5036612.710.716263A12.712.4104411.3258611.2242610.180323B 10.41410.7264211.3258611.4579412.710.716261/2-14UNS 14 1.081 1.8142A 12.661912.4002811.4833411.3563410.50292B 10.744211.125211.5214411.6865412.710.716261/2-16UNS160.861.5882A 12.6644412.4256811.633211.5138210.772142B 10.972811.328411.6687611.823712.711.11253A13.20812.4612411.6687611.5798610.80773B 10.972811.2242611.6687611.785612.711.11251/2-18UNS180.8411.4112A12.6669812.44611.7500411.6382810.988042B11.17611.506211.7830611.9303812.711.11250.4375"11.110.5"螺纹小径螺纹外径MaxMin MaxMinMaxMin Max Min Max Min 公称直径螺纹规格牙数牙高螺距公差代号螺纹外径钻孔直径螺纹中经公差代号螺纹小径螺纹中径1/2-20UNF200.7561.271A 12.6669812.357111.8414811.6789212.527281B 11.328411.607811.874512.0878612.711.508742A 12.6669812.4612411.8414811.7322612.527282B 11.328411.607811.874512.0167412.711.508743A12.712.4942611.874511.7932211.191243B 11.328411.5239811.874511.9811812.711.508741/2-24UNS 240.63 1.0582A 12.6695212.4866411.9811811.8821211.409682B 11.55711.81112.0116612.141212.711.508741/2-27UNS 270.560.9412A 12.6720612.5018812.0599211.9659411.551922B 11.68411.912612.0878612.2097812.711.904981/2-28UNEF280.540.9072A 12.6720612.5069612.0827811.988811.590022B 11.709411.93811.93812.2326412.711.904983A12.712.534912.1107212.039611.617963B 11.709411.8770412.1107212.2021612.711.904981/2-32UN320.4720.7842A 12.674612.522212.1589812.0700811.729722B 11.836412.039612.1843812.2986812.711.904983A12.712.547612.1843812.1183411.755123B 11.836411.9862612.1843812.2707412.711.904989/16-12UNC121.262.1171A 14.2468613.8099812.8727212.674611.727181B 11.988812.44612.9133613.1724414.287512.303762A 14.2468613.957312.8727212.7406411.727182B 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17.894318.427718.986519.278620.637518.254983A20.637520.3098419.0322218.9204617.520923B 17.894318.427718.986519.1820820.637518.2549813/16-12UN121.262.1172A 20.5943220.3047619.2201819.0804818.201642B 18.338818.79619.2633619.4462420.637518.653763A20.637520.3479419.2633619.1592218.117823B 18.338818.6156619.2633619.4005220.637518.6537613/16-16UN160.861.5882A 20.599420.3606419.5681619.443718.70712B 18.92319.278619.6062619.7662820.637519.053A20.637520.3987419.6062619.5148218.74523B 18.92319.1338219.6062619.7256420.637519.0513/16-20UNEF200.7561.272A 20.6044820.3987419.7789819.6672219.093182B 19.253219.55819.81219.9567820.637519.446243A20.637520.4317619.81219.7281819.12623B 19.253219.4614819.81219.9212220.637519.4462413/16-28UN280.540.9072A 20.6070220.4419220.0177419.9212219.524982B 19.659619.862820.0482220.1752220.637519.842483A20.637520.421620.0482219.9745619.555463B 19.659619.8145420.0482220.142220.637519.8424813/16-32UN320.4720.7842A 20.6095620.4571620.0939420.002519.664682B 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20.269220.675621.0464421.2242422.22520.63753A22.22521.9633821.0464420.942320.0663B 20.269220.4927221.0464421.1810622.22520.63757/8-16UN160.861.5882A 22.186921.9481421.1556621.031220.0662B 20.497820.853421.1937621.3537822.22520.63753A22.22521.9862421.1937621.1023220.33273B 20.497820.7213221.1937621.3131422.22520.63757/8-18UNS 180.841 1.4112A 22.1894421.9684621.272521.1556620.51052B 20.70121.031221.3080621.4604622.22521.033747/8-20UNEF200.7561.272A 22.1919821.9862421.3664821.2547220.680682B 20.853421.132821.399521.5442822.22521.033743A22.22522.0192621.399521.3156820.71373B 20.853421.0489821.399521.5087222.22521.033747/8-24UNS 240.63 1.0582A 22.1945222.0116421.5061821.4020420.934682B 21.08221.33621.5366621.6712822.22521.033747/8-27UNS 270.560.9412A 22.1945222.0243421.5823821.4833221.074382B 21.20921.437621.6128621.742422.22521.429987/8-28UN280.540.9072A 22.1945222.0294221.6052421.5087221.112482B 21.234421.46321.6357221.7627222.22521.429983A22.22522.059921.6357221.5620621.142963B 21.234421.4020421.6357221.729722.22521.429987/8-32UN320.4720.7842A 22.1970622.0446621.6814421.5921.252182B 21.361421.564621.7093821.8287622.22521.429983A22.22522.072621.7093821.640821.280123B 21.361421.5112621.7093821.8008222.22521.4299815/16-9UNC91.682.8222A 23.7693223.4162621.9354421.7754220.40892B 22.136121.348721.9786222.186923.812521.033743A23.812523.4594421.9786221.8592420.452083B 22.136121.0972421.9786222.1335623.812521.0337415/16-12UN121.262.1172A 23.7693223.4797622.3951822.250421.249642B 21.513821.97122.4383622.6263223.812521.828763A23.812523.5229422.4383622.3342221.292823B 21.513821.780522.4383622.5780623.812521.8287615/16-16UN160.861.5882A 23.774423.5356422.7431622.6161621.88212B 22.09822.453622.7812622.9463623.812524.7653A23.812523.5737422.7812622.6872821.92023B 22.09822.3088222.7812622.9057223.812522.22515/16-20UNEF200.7561.272A 23.7769423.571222.9514422.8371422.265642B 22.428222.73322.98723.1368623.812522.2253A23.812523.6067622.98722.9006422.30123B 22.428222.6364822.98723.0987623.812522.22515/16-28UN280.540.9072A 23.7820223.6169223.1927423.0911422.699982B 22.834623.037823.2232223.355323.812523.017483A23.812523.647423.2232223.1470222.730463B 22.834622.9895423.2232223.3222823.812523.0174815/16-32UN320.4720.7842A23.7845623.6321623.2689423.1724222.839682B22.961623.139423.2968823.4213423.812523.017480.875"22.2250.9375"23.813。

螺纹规格-美制、英制、公制公制/美制/英制螺纹对照表给大家分享一下 f_a_NpX?,_A型美制螺纹（UNF）常用规格 _,!3_,oiq 牙型角60外螺纹内螺纹 ___UXx^Y2-4 9/16"-19牙14.28 13.08 8j,M4D*&_-6 11/16''-16 17.46 16.1 {lh _szc-8 13/16''-16 20.64 19.28 cM__iO|N@1 -10 1''-14 25.40 23.57 h |t_B __-12 1(3/16)''-12 30.00 28.32 )Al{84<(} -16 1(7/16)''-12 36.51 34.67 Ys$3}LA{-20 1(11/16)''-12 42.86 41.02 SW_7V7_S*Q z{Akh02V@C型JIC37度美制UNF螺纹常用规格 (" G'W牙型角60-4 7/16”-20 11.11 10.03 _e~_xb_Qr-5 1/2”-20 12.70 11.32-6 9/16”-18 14.28 13.08 NH'YgL6*-8 3/4”-16 19.00 17.68 lxv;6_S!J-10 7/8”-14 22.22 20.68 P_|J_&?KbC-12 1(1/16)"-12 26.98 25.15 Ki;_ __ ++ -16 1(5/16)"-12 33.33 31.5 ZF_!BkZ Uo-20 1(5/8)"-12 41.28 39.44 _LX_+_c_Z-24 1(7/8)"-12 47.62 45.8 iDP___@c_g-32 2(1/2)"-12 63.5 61.67 j/5_1_j@^L\e_w;h4_y英制圆柱管螺纹（BSPP）常用规格 dApgz_U@_; 牙型角55-4 1/4”-19 13.157 11.55 |,hu_r8BE\-6 3/8”-19 16.662 14.95 @"%@;>W<t-8 1/2”-14 20.955 18.63 F_)$7 ?')p-12 3/4”-14 26.441 24.11 Q} &f3?_-16 1”-11 33.249 30.29 YZ__@pwhZ<-20 1(1/4)''-11 41.91 38.95 SmU'a_o.\<v{UpdB"_]5英制圆锥管螺纹（BSPT）常用规格 b_sDck <lI 牙型角55基面大径基准距离 A4<_q__07#1/4”-19 13.157 6 _}@E_K'k_3/8”-19 16.662 6.4 .gy5/.SZ1/2”-14 20.955 8.2 R0?/'_gt_3/4”-14 26.441 9.5 _aF4L{_'qK1”-11 33.249 10.4 __Q,Y do_D1(1/4)''-11 41.91 12.7 i_'9mo0bmO@;ir e_^C X "TaT"(1__ G_#_ 美制圆锥管螺纹（NPT） __9_mJ___f 牙型角601/8”-27 10.24 4 3_x_VYo_$g1/4”-18 13.60 4 L8___|v.?J3/8”-18 17.04 4.32 __[ijs_K_1/2”-14 21.22 4.48 _"Lx Hg]')3/4”-14 26.57 4.75 GIry_h_+&a1”-11(1/2)” 33.22 4.6 qBc!A~8K4'1(1/4)”-11.5 41.96 4.83螺纹的一般知识第一章国标螺纹的一般知识一. 螺纹的分类1. 螺纹分内螺纹和外螺纹两种；2. 按牙形分可分为：1）三角形螺纹 2）梯形螺纹 3）矩形螺纹 4）锯齿形螺纹；3. 按线数分单头螺纹和多头螺纹；4. 按旋入方向分左旋螺纹和右旋螺纹两种, 右旋不标注，左旋加LH，如M24×1.5LH；5. 按用途不同分有：米制普通螺纹、用螺纹密封的管螺纹、非螺纹密封的管螺纹、60°圆锥管螺纹、米制锥螺纹等二. 米制普通螺纹1. 米制普通螺纹用大写M表示，牙型角2α=60°（α表示牙型半角）；2. 米制普通螺纹按螺距分粗牙普通螺纹和细牙普通螺纹两种；2.1. 粗牙普通螺纹标记一般不标明螺距，如M20表示粗牙螺纹；细牙螺纹标记必须标明螺距，如M30×1.5表示细牙螺纹、其中螺距为1.5。

PT1-1/2-11 43.40 44.80 43.869 44.232
PT2-11
54.90 56.5 55.412 55.844
美制管螺纹
W 7/8-9 19.50 19.30
W 1-8 22.40 22.00
W 1-1/8-7 25.00 24.80 W 1-1/4-7 28.30 28.00
2.60 3.20 3.70 5.00 6.50 7.90 9.30 10.50 12.00 13.50
16.70 16.50
标准径 规格 使用铰 不使
刀 用铰
PT 1/16-28 6.10 6.20
6.244
6.384
PT 1/8-28 8.10 8.50 8.249 8.388
PT 1/4-19 10.70 11.40 10.962 11.174
1.25 1.55 1.85 2.10 2.40 2.70 2.90 3.50 4.10 4.60
1.305 1.612 1.912 2.197 2.458 2.740 3.022 3.606 4.165 4.724
1.182 1.474 1.756 2.025 2.271 2.551 2.820 3.404 3.963 4.496
0.76 0.85 0.95 1.10 1.25 1.35 1.46 1.60 1.75 1.90
0.785 0.885 0.985 1.142 1.321 1.421 1.521 1.678 1.838 1.979
0.729 0.829 0.929 1.075 1.221 1.321 1.421 1.667 1.713 1.667
29.36
1-1/4-11-1/2 37.31 37.69

美制外螺纹（2A）常用规格极限尺寸表（粗牙）
1.螺胚直径指滚丝前的尺寸，数值为依经验公式计算而得，在实践中需验证。

2.标记示例：10-24UNC-2A（或0.190-24UNC-2A）、3/8-16UNC-2A（或0.375-16UNC-2A）（注：表中上行斜体数值单位为英寸，下行为毫米）
美制外螺纹（2A）常用规格极限尺寸表（细牙）
1.螺胚直径指滚丝前的尺寸，数值为依经验公式计算而得，在实践中需验证
2.标记示例：10-32UNF-2A(或0.190-32UNF-2A)、3/8-24UNF-2A(或0.375-24UNF-2A)
美制内螺纹（2B）常用规格极限尺寸表（粗牙）
1.底孔直径指攻丝前钻孔直径，铸铁、黄铜等较软料取小值，钢、青铜等较硬料取大值。

2.标记示例：10-24UNC-2B(或0.190-24UNC-2B)、3/8-16UNC-2B(或0.375-16UNC-2B)
美制内螺纹（2B）常用规格极限尺寸表（细牙）
1.底孔直径指攻丝前钻孔直径，铸铁、黄铜等较软料取小值，钢、青铜等较硬料取大值。

2.标记示例：10-32UNF-2B(或0.190-32UNF-2B)、3/8-24UNF-2B(或0.375-24UNF-2B)。

规格
标准径
2级牙钻孔径 最大 最小
1/4 -32 5.6 5.689 5.487
牙 套 螺 纹攻 用
规格
标准径
下孔径 最大 最小
M10*1.5 10.5 10.62 10.37
美制管螺纹
钻孔径
规格
1-1/4 -111/2
NPT
使用铰刀时
37.31
英制管螺纹(PS,PF,PT)
规格
标准径
2 - 11 PF 57
NPT
不用铰刀时
37.69
NPS
38.1
螺纹(PS,PF,PT)
钻孔径
最大
最小
57.296 56.656
针车用螺纹
规格
标准径
最大
最小
SM1/16 -80 1.25 1.281 1.211
美制特殊螺纹(UNS)
规格（2B内螺纹) 螺纹外径
钻孔径
最大
最小
1/4-36 UNS 2B 6.3标准径
2级牙钻孔径 最大 最小
M1.4*0.3 1.1 1.142 1.075
螺纹查
公制细螺纹
规格
标准径
M4.5*0.5
4
询
美制粗螺纹(UNC)
规格
标准径
2级牙钻孔径 最大 最小
3/8 -16
8 8.153 7.798
美制细螺纹(UNF)
规格
标准径
3/8 -24 8.5
美制特细螺纹(UNEF)
纹查询表
公制细螺纹
2级牙钻孔径
最大
最小
公制迫牙丝攻钻孔径
规格
精度
最大
最小
4.099 3.959

美制外螺纹（2A）常用规格极限尺寸表（粗牙）
1.螺胚直径指滚丝前的尺寸，数值为依经验公式计算而得，在实践中需验证。

2.标记示例：10-24UNC-2A(或、3/8-16UNC-2A(或
（注：表中上行斜体数值单位为英寸，下行乘为毫米）
美制外螺纹（2A）常用规格极限尺寸表（细牙）
1.螺胚直径指滚丝前的尺寸，数值为依经验公式计算而得，在实践中需验证。

2.标记示例：10-32UNF-2A(或、3/8-24UNF-2A(或
美制内螺纹（2B）常用规格极限尺寸表（粗牙）
1.底孔直径指攻丝前钻孔直径，铸铁、黄铜等较软料取小值，钢、青铜等较硬料取大值。

2.标记示例：10-24UNC-2B(或、3/8-16UNC-2B(或
美制内螺纹（2B）常用规格极限尺寸表（细牙）
1.底孔直径指攻丝前钻孔直径，铸铁、黄铜等较软料取小值，钢、青铜等较硬料取大值。

2.标记示例：10-32UNF-2B(或、3/8-24UNF-2B(或。

螺纹规格-美制、英制、公制美制细牙UNF 2A 外螺纹大径UNFUN 2B内螺纹小径（UN、UNF）序号规格型号最大最小公差最小最大公差1 7/16"-20 11.079 10.874 0.206 9.728 10.033 0.3052 1/2"-20 12.667 12.461 0.206 11.328 11.608 0.2793 9/16"-18 14.252 14.031 0.221 12.751 13.081 0.3304 3/4"-16 19.012 18.773 0.239 17.323 17.678 0.3565 7/8"-14 22.184 21.923 0.262 20.269 20.676 0.406-12 26.944 26.655 0.290 24.689 25.146 0.457 6 11/16-12 33.294 33.005 0.290 31.039 31.496 0.457 7 15/168 15/-12 41.229 40.940 0.290 38.989 39.446 0.4578-12 47.579 47.290 0.290 45.339 45.796 0.457 9 17/8-12 63.452 63.162 0.290 61.214 61.671 0.457 10 21/2公制细牙6g外螺纹大径6H内螺纹小径1 M10*1 9.974 9.794 0.180 8.917 9.157 0.2402 M12*1.5 11.968 11.732 0.236 10.376 10.676 0.3003 M14*1.5 13.968 13.732 0.236 12.376 12.676 0.3004 M16*1.5 15.968 15.732 0.236 14.376 14.676 0.3005 M18*1.5 17.968 17.732 0.236 16.376 16.676 0.3006 M20*1.5 19.968 19.732 0.236 18.376 18.676 0.3007 M22*1.5 21.968 21.732 0.236 20.376 20.676 0.3008 M24*1.5 23.968 23.732 0.236 22.376 22.676 0.3009 M26*1.5 25.968 25.732 0.236 24.376 24.676 0.30010 M27*1.5 26.968 26.732 0.236 25.376 25.676 0.30011 M30*1.5 29.968 29.732 0.236 28.376 28.676 0.3000.375 12 M27*2 26.962 26.682 0.280 24.83525.21013 M30*2 29.962 29.682 0.280 27.835 28.210 0.37514 M33*2 32.962 32.682 0.280 30.835 31.210 0.37515 M36*2 35.962 35.682 0.280 33.835 34.210 0.37516 M42*2 41.962 41.682 0.280 39.835 40.210 0.375英制管螺纹1 G1/8-28 9.728 9.514 0.214 8.566 8.848 0.2822 G1/4-19 13.157 12.907 0.250 11.445 11.890 0.4453 G3/8-19 16.662 16.412 0.250 14.950 15.395 0.4454 G1/2-14 20.955 20.671 0.284 18.631 19.172 0.5415 G3/4-14 26.441 26.157 0.284 24.117 24.658 0.5416 G1-11 33.249 32.889 0.360 30.291 30.931 0.640-11 41.910 41.550 0.360 38.952 39.592 0.6407 G11/4-11 47.803 47.443 0.360 44.845 45.485 0.6408 G11/2公制/美制/英制螺纹对照表给大家分享一下 A型美制螺纹（UNF）常用规格牙型角60外螺纹内螺纹 -4 9/16"-19牙 14.28 13.08 -6 11/16''-16 17.46 16.1 -8 13/16''-16 20.64 19.28 -10 1''-14 2 5.40 23.57 -12 1(3/16)''-12 30.00 28.32 -16 1(7/16)''-12 36.51 34.67 -20 1(11/16)' '-12 42.86 41.02 C型JIC37度美制UNF螺纹常用规格牙型角60-4 7/16”-20 11.11 10.03 -5 1/2”-20 12.70 11.32-6 9/16”-18 14.28 13.08 -83/4”-16 19.00 17.68 -10 7/8”-14 22.22 20.68 -12 1(1/16)"-12 26.98 25.15 -16 1 (5/16)"-12 33.33 31.5 -20 1(5/8)"-12 41.28 39.44 -24 1(7/8)"-12 47.62 45.8 -32 2(1/2)"-12 63.5 61.67 英制圆柱管螺纹（BSPP）常用规格牙型角55-4 1/4”-19 13.157 11.55 -6 3/8”-19 16.662 14.95 -8 1/2”-14 20.955 18.63 -12 3/4”-14 26.441 24.11 -16 1”-11 33.249 30.29 -20 1(1/4)''-11 41.91 38.95 英制圆锥管螺纹（BSPT）常用规格牙型角55基面大径基准距离1/4”-19 13.157 6 3/8”-19 16.662 6.4 1/2”-14 20.955 8.2 3/4”-14 26.441 9.5 1”-11 33.249 10.4 1(1/4)''-11 41.91 12.7 美制圆锥管螺纹（NPT）牙型角601/8”-27 10.24 4 1/4”-18 13.60 4 3/8”-18 17.04 4.32 1/2”-14 21.22 4.48 3/4”-14 26.57 4.75 1”-11(1/2)” 33.22 4.6 1(1/4)”-11.5 41.96 4.83螺纹的一般知识第一章国标螺纹的一般知识一. 螺纹的分类1. 螺纹分内螺纹和外螺纹两种；2. 按牙形分可分为：1）三角形螺纹2）梯形螺纹3）矩形螺纹4）锯齿形螺纹；3. 按线数分单头螺纹和多头螺纹；4. 按旋入方向分左旋螺纹和右旋螺纹两种, 右旋不标注，左旋加LH，如M24×1.5LH；5. 按用途不同分有：米制普通螺纹、用螺纹密封的管螺纹、非螺纹密封的管螺纹、60°圆锥管螺纹、米制锥螺纹等二. 米制普通螺纹1. 米制普通螺纹用大写M表示，牙型角2α=60°（α表示牙型半角）；2. 米制普通螺纹按螺距分粗牙普通螺纹和细牙普通螺纹两种；2.1. 粗牙普通螺纹标记一般不标明螺距，如M20表示粗牙螺纹；细牙螺纹标记必须标明螺距，如M30×1.5表示细牙螺纹、其中螺距为1.5。

美制螺纹底孔 单位:
注：UNC：粗牙系列， UNF：细牙系列，
UNEF：超细牙系列， UN：不变螺距系列， UNS：特殊系列
美制统一螺纹，在英寸制国家广泛采用，该类螺纹分三个系列：粗牙系列UNC，细牙系列UNF，特细牙系列UNFF，外加一个不变螺距系列UN。

标注方法：螺纹直径—每英寸牙数系列代号—精度等级
示例：
粗牙系列 3/8—16 UNC—2A
细牙系列 3/8—24 UNF—2A
特细牙系列 3/8—32 UNFF—2A
不变螺距系列 3/8—20 UN—2A
第一、位数字3/8（分数或小数）表示螺纹外径，单位为英寸，转换为米制单位mm要乘以25.4，即3/8×25.4=9.525mm；
第二、位数字16、24、32、20为每英寸牙数(在25.4mm长度上的牙数)；等级。

第三、位以后的文字代号UNC、UNF、UNFF、UN为系列代号，最后两位2A为精度。

螺纹规格-美制、英制、公制公制/美制/英制螺纹对照表给大家分享一下 A型美制螺纹（UNF）常用规格牙型角60外螺纹内螺纹 -4 9/16"-19牙 14.28 13.08 -6 11/16''-16 17.46 16.1 -8 13/16''-16 20.64 19.28 -10 1''-14 2 5.40 23.57 -12 1(3/16)''-12 30.00 28.32 -16 1(7/16)''-12 36.51 34.67 -20 1(11/16)' '-12 42.86 41.02 C型JIC37度美制UNF螺纹常用规格牙型角60-4 7/16”-20 11.11 10.03 -5 1/2”-20 12.70 11.32-6 9/16”-18 14.28 13.08 -83/4”-16 19.00 17.68 -10 7/8”-14 22.22 20.68 -12 1(1/16)"-12 26.98 25.15 -16 1 (5/16)"-12 33.33 31.5 -20 1(5/8)"-12 41.28 39.44 -24 1(7/8)"-12 47.62 45.8 -32 2(1/2)"-12 63.5 61.67 英制圆柱管螺纹（BSPP）常用规格牙型角55-4 1/4”-19 13.157 11.55 -6 3/8”-19 16.662 14.95 -8 1/2”-14 20.955 18.63 -12 3/4”-14 26.441 24.11 -16 1”-11 33.249 30.29 -20 1(1/4)''-11 41.91 38.95 英制圆锥管螺纹（BSPT）常用规格牙型角55基面大径基准距离1/4”-19 13.157 6 3/8”-19 16.662 6.4 1/2”-14 20.955 8.2 3/4”-14 26.441 9.5 1”-11 33.249 10.4 1(1/4)''-11 41.91 12.7 美制圆锥管螺纹（NPT）牙型角601/8”-27 10.24 4 1/4”-18 13.60 4 3/8”-18 17.04 4.32 1/2”-14 21.22 4.48 3/4”-14 26.57 4.75 1”-11(1/2)” 33.22 4.6 1(1/4)”-11.5 41.96 4.83螺纹的一般知识第一章国标螺纹的一般知识一. 螺纹的分类1. 螺纹分内螺纹和外螺纹两种；2. 按牙形分可分为：1）三角形螺纹2）梯形螺纹3）矩形螺纹4）锯齿形螺纹；3. 按线数分单头螺纹和多头螺纹；4. 按旋入方向分左旋螺纹和右旋螺纹两种, 右旋不标注，左旋加LH，如M24×1.5LH；5. 按用途不同分有：米制普通螺纹、用螺纹密封的管螺纹、非螺纹密封的管螺纹、60°圆锥管螺纹、米制锥螺纹等二. 米制普通螺纹1. 米制普通螺纹用大写M表示，牙型角2α=60°（α表示牙型半角）；2. 米制普通螺纹按螺距分粗牙普通螺纹和细牙普通螺纹两种；2.1. 粗牙普通螺纹标记一般不标明螺距，如M20表示粗牙螺纹；细牙螺纹标记必须标明螺距，如M30×1.5表示细牙螺纹、其中螺距为1.5。