美制螺纹标准大全外螺纹 ExternalNominal级别公差大径Major Diameter中径Pitch Diameter小径UNRbdh Min MinMax MinMinorSine,ThreaClassAllowanMaxce0-80 UNF2A0.00050.05950.05630.05140.050.04463A00.060.05680.05190.0510.04511-64 UNC2A0.00060.07240.06860.06230.060.05383A00.0730.06920.06290.0610.05441-72 UNF2A0.00060.07240.06890.06340.0620.05593A00.0730.06950.0640.0630.05652-56 UNC2A0.00060.08540.08130.07380.0720.06423A00.0860.08190.07440.0730.06482-64 UNF2A0.00060.08540.08160.07530.0730.06683A00.0860.08220.07590.0740.06743-48 UNC2A0.00070.09830.09380.08480.0830.07343A00.0990.09450.08550.0840.07413-56 UNF2A0.00070.09830.09420.08670.0850.07713A00.0990.09490.08740.0860.07784-40 UNC2A0.00080.11120.10610.0950.0930.08143A00.1120.10690.09580.0940.08224-48 UNF2A0.00070.11130.10680.09780.0950.08643A00.1120.10750.09850.0970.08715-40 UNC2A0.00080.12420.11910.1080.1050.09443A00.1250.11990.10880.1070.09525-44 UNF2A0.00070.12430.11950.10950.1070.09723A00.1250.12020.11020.1080.09796-32 UNC2A0.00080.13720.13120.11690.1140.13A00.1380.1320.11770.1160.10086-40 UNF2A0.00080.13720.13210.1210.1180.10743A00.1380.13290.12180.120.10828-32 UNC2A0.00090.16310.15710.14280.140.12593A00.1640.1580.14370.1420.12688-36 UNF2A0.00080.16320.15770.14520.1420.13013A00.1640.15850.1460.1440.130910-24 UNC2A0.0010.1890.18180.16190.1590.13943A00.190.18280.16290.160.140410-28 UNS2A0.0010.1890.18250.16580.1630.146410-32 UNF2A0.00090.18910.18310.16880.1660.15193A00.190.1840.16970.1670.152810-36 UNS2A0.00090.18910.18360.17110.1680.15610-40 UNS2A0.00090.18910.1840.17290.170.159210-48 UNS2A0.00080.18920.18470.17570.1730.164410-56 UNS2A0.00070.18930.18520.17770.1750.168112-24 UNC2A0.0010.2150.20780.18790.1850.16543A00.2160.20880.18890.1860.166412-28 UNF2A0.0010.2150.20850.19180.1890.17243A00.2160.20950.19280.190.173412-32UNEF2A0.00090.21510.20910.19480.1920.17793A00.2160.210.19570.1930.178812-36 UNS2A0.00090.21510.20960.19710.1940.182112-40 UNS2A0.00090.21510.210.19890.1960.183512-48 UNS2A0.00080.21520.21070.20170.1990.190412-56 UNS2A0.00070.21530.21120.20370.2010.19411A0.00110.24890.23670.21640.2110.18941/4-20UNC2A0.00110.24890.24080.23670.21640.2130.18943A00.250.24190.21750.2150.19051/4-24UNS2A0.00110.24890.24170.22180.2180.19931/4-27UNS2A0.0010.2490.24230.22490.2210.20491A0.0010.2490.23920.22580.2210.20641/4-28UNF2A0.0010.2490.24250.22580.2230.2064内螺纹 Internal级别Class2B3B2B3B2B3B2B3B2B3B2B3B2B3B2B3B2B3B2B3B2B3B2B3B2B3B2B3B2B3B2B3B2B2B3B2B2B2B2B2B3B2B3B2B3B2B2B2B2B1B2B3B2B2B1B2B小径MinorMin Max0.04650.05140.04650.05140.05610.06230.05610.06230.0580.06350.0580.06350.06670.07370.06670.07370.06910.07530.06910.07530.07640.08450.07640.08450.07970.08650.07970.08650.08490.09390.08490.09390.08940.09680.08940.09680.09790.10620.09790.10620.10040.10790.10040.10790.1040.1140.1040.1140.1110.1190.1110.11860.130.1390.130.13890.1340.1420.1340.14160.1450.1560.1450.15550.1510.160.1560.1640.1560.16410.160.1660.1630.1690.1670.1720.1710.1750.1710.1810.1710.18070.1770.1860.1770.18570.1820.190.1820.18950.1860.1920.1890.1950.1930.1980.1970.2010.1960.2070.1960.2070.1960.20670.2050.2150.210.2190.2110.220.2110.22第 1 页，共 3 页2013-4-9外螺纹 ExternalNominalSine,Threa1/4-32UNEF1/4-36UNS1/4-40UNS1/4-48UNS1/4-56UNS5/16-18UNC5/16-20UN级别Class3A2A3A2A2A2A2A1A2A3A2A3A1A5/16-24UNF2A3A5/16-27UNS2A5/16-28UN2A3A5/16-32UNEF2A3A5/16-36UNS2A5/16-40UNS2A5/16-48UNS2A1A3/8-16UNC2A3A3/8-18UNS2A3/8-20 UN2A3A1A3/8-24UNF2A3A3/8-27UNS2A3/8-28 UN2A3A3/8-32UNEF2A3A3/8-36UNS2A3/8-40UNS0.390-272AUNS2A1A7/16-14UNC2A3A7/16-16UN2A3A7/16-18UNS2A1A7/16-20UNF2A3A7/16-24UNS2A7/16-27UNS2A7/16-28UNEF2A3A7/16-32UN2A3A1/2-12UNS2A3A1A公差Allowan0ce0.00100.00090.00090.00080.00080.00120.001200.001200.00110.001100.0010.00100.00100.00090.00090.00080.00130.001300.00130.001200.00110.001100.00110.001100.00100.0010.00090.00110.00140.001400.001400.00130.00130.001300.00110.00110.001100.00100.001600.0015大径Major Diameter中径Pitch Diameter小径UNRbdhMax Min MinMax MinMinor0.250.24350.22680.2240.20740.2490.2430.22870.2260.21180.250.2440.22970.2270.21280.24910.24360.23110.2280.21610.24910.2440.23290.230.21930.24920.24470.23570.2330.22430.24920.24510.23760.2350.2280.31130.29820.27520.2690.24520.31130.30260.29820.27520.2710.24520.31250.30380.27640.2730.24640.31130.30320.27880.2750.25180.31250.30440.280.2770.2530.31140.30060.28430.2790.26180.31140.30420.28430.2810.26180.31250.30530.28540.2830.26290.31150.30480.28740.2840.26740.31150.3050.28830.2850.26890.31250.3060.28930.2870.26990.31150.30550.29120.2880.27430.31250.30650.29220.290.27530.31160.30610.29360.2910.27850.31160.30650.29540.2930.28180.31170.30720.29820.2960.28690.37370.35950.33310.3270.29920.37370.36430.35950.33310.3290.29920.3750.36560.33440.3310.30050.37370.3650.33760.3330.30760.37380.36570.34130.3370.31430.3750.36690.34250.3390.31550.37390.36310.34680.3410.32430.37390.36670.34680.3430.32430.3750.36780.34790.3450.32540.37390.36720.34980.3460.32980.37390.36740.35070.3470.33130.3750.36850.35180.3490.33240.3740.3680.35370.350.33680.3750.3690.35470.3520.33780.3740.36850.3560.3530.34090.37410.3690.35790.3550.34430.38890.38220.36480.3610.34480.43610.42060.38970.3830.35110.43610.42580.42060.38970.3850.35110.43750.42720.39110.3880.35250.43610.42670.39550.3910.36160.43750.42810.39690.3940.3630.43620.42750.40010.3960.37010.43620.4240.40370.3980.37670.43620.42810.40370.40.37670.43750.42940.4050.4020.3780.43640.42920.40930.4060.38680.43640.42970.41230.4090.39230.43640.42990.41320.410.39380.43750.4310.41430.4120.39490.43650.43050.41620.4130.39930.43750.43150.41720.4150.40030.49840.4870.44430.4390.39920.50.48860.44590.4420.40080.49850.48220.44850.4410.4069内螺纹 Internal级别Class3B2B3B2B2B2B2B1B2B3B2B3B1B2B3B2B2B3B2B3B2B2B2B1B2B3B2B2B3B1B2B3B2B2B3B2B3B2B2B2B1B2B3B2B3B2B1B2B3B2B2B2B3B2B3B2B3B1B小径MinorMin Max0.2110.2190.2160.2240.2160.22290.220.2260.2230.2290.2270.2320.2310.2350.2520.2650.2520.2650.2520.2630.2580.270.2580.2680.2670.2770.2670.2770.2670.27540.2720.2810.2740.2820.2740.28070.2790.2860.2790.28470.2820.2890.2850.2910.290.2950.3070.3210.3070.3210.3070.31820.3150.3280.3210.3320.3210.32970.330.340.330.340.330.33720.3350.3440.3360.3450.3360.34260.3410.3490.3410.34690.3450.3520.3480.3540.350.3590.360.3760.360.3760.360.37170.370.3840.370.380.3770.390.3830.3950.3830.3950.3830.39160.3920.4020.3970.4060.3990.4070.3990.40510.4040.4110.4040.40940.410.4280.410.42230.4170.434第 2 页，共 3 页2013-4-9外螺纹 ExternalNominalSine,Threa1/2 UNC1/2-14UNS级别Class2A3A2A公差大径Major Diameter中径Pitch Diameter小径UNRbdhAllowanMax Min MinMax MinMinorce0.00150.49850.48760.48220.44850.4440.406900.50.48910.450.4460.40840.00150.49850.48820.45210.4470.4135内螺纹 Internal小径Minor级别ClassMin Max2B0.4170.4343B0.4170.42842B0.4230.438第 3 页，共 3 页2013-4-9