公制美制英制螺纹对照表

公制/美制/英制螺纹对照表

A型美制螺纹（UNF）常用规格

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 25.40 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-4 7/16”-20 11.11 10.03

-5 1/2”-20 12.70 11.32

-6 9/16”-18 14.28 13.08

-8 3/4”-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

-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）

1/8”-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

美制外螺纹（2A）常用规格极限尺寸表（粗牙）

打印| 推荐| 评分

2007-4-20 16:33

3/8-16 0.3643 0.3737 0.3287 0.3331 0.2970 8.40 8.44

(0.375-16) 9.2532 9.4920 8.3490 8.4607 7.5438

7/16-14 0.4258 0.4361 0.3850 0.3897 0.3485 9.83 9.87

(0.4375-14) 10.8153 11.0769 9.7790 9.8984 8.8519

1/2-13 0.4876 0.4985 0.4435 0.4485 0.4041 11.34 11.38

(0.50-13) 12.3850 12.6619 11.2649 11.3919 10.2641

9/16-12 0.5495 0.5609 0.5016 0.5068 0.4587 12.80 12.84

(0.5625-12) 13.9573 14.2469 12.7406 12.8727 11.6510

5/8-11 0.6113 0.6234 0.5589 0.5644 0.5119 14.27 14.32

(0.625-11) 15.5270 15.8344 14.1961 14.3358 13.0023

3/4-10 0.7353 0.7482 0.6773 0.6832 0.6255 17.28 17.33

(0.750-10) 18.6766 19.0043 17.2034 17.3533 15.8877

7/8-9 0.8592 0.8731 0.7946 0.8009 0.7368 20.27 20.32

(0.875-9) 21.8237 22.1767 20.1828 20.3429 18.7147

1"-8 0.9830 0.9980 0.9100 0.9168 0.8446 23.22 23.27

(1.000-8) 24.9682 25.3492 23.1140 23.2867 21.4528

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）

lanjibingyu

2007-4-20 16:34

美制外螺纹（2A）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8-36 UNF 0.1577 0.1632 0.1424 0.1452 0.1291 3.65 3.67

(0.164-36) 4.0056 4.1453 3.6170 3.6881 3.2791

10-32 0.1831 0.1891 0.1658 0.1688 0.1508 4.24 4.27

(0.190-32) 4.6507 4.8031 4.2113 4.2875 3.8303

12-28 0.2085 0.2150 0.1886 0.1918 0.1712 4.82 4.85

(0.216-28) 5.2959 5.4610 4.7904 4.8717 4.3485

1/4-28 0.2425 0.2490 0.2225 0.2258 0.2052 5.69 5.71

(0.250-28) 6.1595 6.3246 5.6515 5.7353 5.2121

5/16-24 0.3042 0.3114 0.2806 0.2843 0.2603 7.17 7.20

(0.3175-24) 7.7267 7.9096 7.1272 7.2212 6.6116

3/8-24 0.3667 0.3739 0.3430 0.3468 0.3228 8.75 8.78

(0.375-24) 9.3142 9.4971 8.7122 8.8087 8.1991

7/16-20 0.4281 0.4362 0.3995 0.4037 0.3749 10.19 10.23

(0.4375-20) 10.8737 11.0795 10.1473 10.2540 9.5225

1/2-20 0.4906 0.4987 0.4619 0.4662 0.4374 11.78 11.82

(0.50-20) 12.4612 12.6670 11.7323 11.8415 11.1100

9/16-18 0.5524 0.5611 0.5205 0.5250 0.4929 13.27 13.31

(0.5625-18) 14.0310 14.2519 13.2207 13.3350 12.5197

5/8-18 0.6149 0.6236 0.5828 0.5875 0.5554 14.85 14.89

(0.625-18) 15.6185 15.8394 14.8031 14.9225 14.1072

3/4-16 0.7391 0.7485 0.7029 0.7079 0.6718 17.91 17.95

(0.750-16) 18.7731 19.0119 17.8537 17.9807 17.0637

7/8-14 0.8631 0.8734 0.8216 0.8270 0.7858 20.93 20.97

(0.875-14) 21.9227 22.1844 20.8686 21.0058 19.9593

1"-12 0.9868 0.9982 0.9382 0.9441 0.8960 23.90 23.95

(1.000-12) 25.0647 25.3543 23.8303 23.9801 22.7584

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)

美制外螺纹（2A）常用规格极限尺寸表（粗牙）