美制螺纹标准对照表

1、美制螺纹标准对照表美制外螺纹（2A）常用规格极限尺寸表（粗牙）公称尺寸和 每英寸牙数螺纹系列代号大径极限中径极限小径 max螺胚直径最小最大最小最大最小最大8-320.15710.16310.13990.14280.12483.583.61(0.164-32)3.99034.14273.55353.62713.169910-240.18180.18900.15860.16190.13794.074.10(0.190-24)4.61774.80064.02844.11233.502712-240.20780.21500.18450.18790.16394.724.75(0.216-24)5.27

2、815.46104.68634.77274.16311/4-200.24080.24890.21270.21640.18765.455.48(0.250-20)6.11636.32215.40265.49664.76505/16-180.30260.31130.27120.27520.24316.946.98(0.3175-18)7.68607.90706.88856.99016.17473/8-160.36430.37370.32870.33310.29708.408.44(0.375-16)9.25329.49208.34908.46077.54387/16-14UNC0.42580.43

3、610.38500.38970.34859.839.87(0.4375-14)10.815311.07699.77909.89848.85191/2-130.48760.49850.44350.44850.404111.3411.38(0.50-13)12.385012.661911.264911.391910.26419/16-120.54950.56090.50160.50680.458712.8012.84(0.5625-12)13.957314.246912.740612.872711.65105/8-110.61130.62340.55890.56440.511914.2714.32

4、(0.625-11)15.527015.834414.196114.335813.00233/4-100.73530.74820.67730.68320.625517.2817.33(0.750-10)18.676619.004317.203417.353315.88777/8-90.85920.87310.79460.80090.736820.2720.32(0.875-9)21.823722.176720.182820.342918.71471"-80.98300.99800.91000.91680.844623.2223.27(1.000-8)24.968225.349223.

5、114023.286721.45281. 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）美制内螺纹（2B）常用规格极限尺寸表（粗牙）公称尺寸和每英寸牙数螺纹系列代号大径极限中径极限小径 max螺胚直径最小最大最小最大最小最大8-360.15770.16320.14240.14520.12913.653.67(0.164-36)4.00564.14533.61703.68813.279110-320

6、.18310.18910.16580.16880.15084.244.27(0.190-32)4.65074.80314.21134.28753.830312-280.20850.21500.18860.19180.17124.824.85(0.216-28)5.29595.46104.79044.87174.34851/4-280.24250.24900.22250.22580.20525.695.71(0.250-28)6.15956.32465.65155.73535.21215/16-240.30420.31140.28060.28430.26037.177.20(0.3175-24)

7、7.72677.90967.12727.22126.61163/8-240.36670.37390.34300.34680.32288.758.78(0.375-24)9.31429.49718.71228.80878.19917/16-20UNF0.42810.43620.39950.40370.374910.1910.23(0.4375-20)10.873711.079510.147310.25409.52251/2-200.49060.49870.46190.46620.437411.7811.82(0.50-20)12.461212.667011.732311.841511.11009

8、/16-180.55240.56110.52050.52500.492913.2713.31(0.5625-18)14.031014.251913.220713.335012.51975/8-180.61490.62360.58280.58750.555414.8514.89(0.625-18)15.618515.839414.803114.922514.10723/4-160.73910.74850.70290.70790.671817.9117.95(0.750-16)18.773119.011917.853717.980717.06377/8-140.86310.87340.82160.

9、82700.785820.9320.97(0.875-14)21.922722.184420.868621.005819.95931"-120.98680.99820.93820.94410.896023.9023.95(1.000-12)25.064725.354323.830323.980122.75841. 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)公称尺寸和每英寸牙数螺纹系列代号小径极限中径极限大径 min底孔直径最小

10、最大最小最大最小最大8-320.13000.13900.14370.14750.16403.403.50(0.164-32)3.30203.53063.65003.74654.165610-240.14500.15600.16290.16720.19003.753.90(0.190-24)3.68303.96244.13774.24694.826012-240.17100.18100.18890.19330.21604.404.55(0.216-24)4.34344.59744.79814.90985.48641/4-200.19600.20700.21750.22240.25005.055.

11、20(0.250-20)4.97845.25785.52455.64906.35005/16-180.25200.26500.27640.28170.31256.456.60(0.3175-18)6.40086.73107.02067.15527.93753/8-160.30700.32100.33440.34010.37507.858.00(0.375-16)7.79788.15348.49388.63859.52507/16-14UNC0.36000.37600.39110.39720.43759.209.40(0.4375-14)9.14409.55049.933910.088911.1

12、1251/2-130.41700.43400.45000.45650.500010.6510.90(0.50-13)10.591811.023611.430011.595112.70009/16-120.47200.49000.50840.51520.562512.0512.30(0.5625-12)11.988812.446012.913413.086114.28755/8-110.52700.54600.56600.57320.625013.4513.70(0.625-11)13.385813.868414.376414.559315.87503/4-100.64200.66300.685

13、00.69270.750016.4016.70(0.750-10)16.306816.840217.399017.594619.05007/8-90.75500.77800.80280.81100.875019.3019.60(0.875-9)19.177019.761220.391120.599422.22501"-80.86500.89000.91880.92761.000022.1022.40(1.000-8)21.971022.606023.337523.561025.40001. 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

14、-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)公称尺寸和每英寸牙数螺纹系列代号小径极限中径极限大径 min底孔直径最小最大最小最大最小最大8-360.13400.14200.14600.14960.16403.453.67(0.164-36)3.40363.60683.70843.79984.165610-320.15600.16400.16970.17360.19004.004.27(0.190-32)3.96244.16564.31044.40944.826012-280.177

15、00.18600.19280.19700.21604.554.85(0.216-28)4.49584.72444.89715.00385.48641/4-280.21100.22000.22680.23110.25005.405.71(0.250-28)5.35945.58805.76075.86996.35005/16-240.26700.27700.28540.29020.31256.857.20(0.3175-24)6.78187.03587.24927.37117.93753/8-240.33000.34000.34790.35280.37508.458.78(0.375-24)8.3

16、8208.63608.83678.96119.52507/16-20UNF0.38300.39500.40500.41040.43759.8510.23(0.4375-20)9.728210.033010.287010.424211.11251/2-200.44600.45700.46750.47310.500011.4011.82(0.50-20)11.328411.607811.874512.016712.70009/16-180.50200.51500.52640.53230.562512.8513.31(0.5625-18)12.750813.081013.370613.520414.

17、28755/8-180.56500.57800.58890.59490.625014.4514.89(0.625-18)14.351014.681214.958115.110515.87503/4-160.68200.69600.70940.71590.750017.4017.95(0.750-16)17.322817.678418.018818.183919.05007/8-140.79800.81400.82860.83560.875020.3520.97(0.875-14)20.269220.675621.046421.224222.22501"-120.91000.92800

18、.94590.95351.000023.9023.95(1.000-12)23.114023.571224.025924.218925.40001. 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)Screw SizeClass ThreadMajor DiameterPitch DiameterMinor DiameterBasic3Max.Min.BasicMax.Min.0-802A0.06000.05950.05630.051

19、90.05140 04960.04420-803A0.06000.06000.05680.05190.05190.05060.04471-642A0.07300.07240.06860.06290.06230.06030.05321-643A0.07300.07300.06920.06290.06290.06140.05381-722A0.07300.07240.06890.06400.06340.06150.05541-723A0.07300.07300.06950.06400.06400.06260.05602-562A0.08600.08540.08130.07440.07380.071

20、70.06352-563A0.08600.08600.08190.07440.07440.07280.06412-642A0.08600.08540.08160.07590.07530.07330.06622-643A0.08600.08600.08220.07590.07590.07440.06683-482A0.09900.09830.09380.08550.08480.08250.07273-483A0.09900.09900.0945008550.08550.08380.07343-562A0.09900.09830.09420.08740.08670.08450.07643-563A

21、0.09900.09900.09490.08740.08740.08580.07714-402A0.11200.11120.10610.09580.09500.09250.08054-403A0.11200.11200.10690.09580.09580.09390.08134-482A0.11200.11130.10680.09850.09780.09540.08574-483A0.11200.11200.10750.09850.09850.09670.08645-402A0.12500.12420.11910.10880.10800.10540.09355-403A0.12500.1250

22、0.11990.10880.10880.10690.09435-442A0.12500.12430.11950.11020.10950.10700.09645-443A0.12500.12500.12020.11020.11020.10830.09716-322A0.13800.13720.13120.11770.11690.11410.09896-323A0.13800.13800.13200.11770.11770.11560.09976-402A0.13800.13720.13210.12180.12100.11840.10656-403A0.13800.13800.13290.1218

23、0.12180.11980.10738-322A0.16400.16310.15710.14370.14280.13990.12488-323A0.16400.16400.15800.14370.14370.14150.12578-362A0.16400.16320.15770.14600.14520.14240.12918-363A0.16400.16400.15850.14600.14600.14390.129910-242A0.19000.18900.18180.16290.16190.15860.137910-243A0.19000.19000.18280.16290.16290.16

24、040.138910-322A0.19000.18910.18310.16970.16880.16580.150810-323A0.19000.19000.18400.16970.16970.16740.15171/4-202A0.25000.24890.24080.21750.21640.21270.187611 203A0.25000.25000.24190.21750.21750.21470.18871/4-282A0.25000.24900.24250.22680.22580.22250.20521 4-283A0.25000.25000.24350.22680.22680.22430

25、.20625/16-182A0.31250.31130.30260.27640.27520.27120.24315/16-183A0.31250.31250.30380.27640.27640.27340.24435/16-24.2A0.31250.31140.30420.28540.28430.28060.26035/16-243A0 3125031250 30530 28540 28540 28270 26143 8-162A0 3750037370 36430 33440 3331032870 2970EA0 37500 37500 36560 33440 33440 33110 29X

26、33 8-24JA0.37500.37390.36670.34790.34680.34300.32283/8-243A0.37500.37500.36780.34790.34790.3450032397/16-142A0.43750.43610.42580.39110.389703850034857/16 113A0.43750.43750.-12720.39110.39110.38760.34997/16-202A0.43750.43620.42810.40500.40370.39950.37497/16-203A0.43750.43750.42940.40500.40500.40190.3

27、7621 2-132A0.50000.49850.48760.45000.44850.44350.40411/2-133A0.50000.50000.48910.45000.45000.44630.40561/2-202A0 5000049870 49060 46750 46620 4619043741/2-203A0 5000o -sooo0 49190 46750 46750 46430 43875/8-1 12A0 625006234()61130 566()0 56440 55890 51195 8-113A0.62500.62500.61290.56600.56600.56190.5

28、1355 8 182A0.62500.62360.61490.52890.58750.58280.55545/8-183A0 625006250061630 58890 58890 58540 55683 4-102A0.75000.74820.73530.68500.68320.67730.62553 1 103A0.75000.75000.73710.62500.68500.62060.62733/4-162A0.75000.74850.73910.70940.70790.70290.67183/4-16.3A0.75000.75000.74060.70940.70940.70560.67337/8 -92A0.87500.87310 5920.80280.80090.79460.73687/8 -93A0.87500.87500.86110.80280.80280.79810.73877/8-142A0.87500.87340.86310.62860.82700.82160.78587/8-14.3A0.B7500.87500 S647008286()82450.78741 -82A1.00000.99800.98300.91880