螺紋代號

每 25.4mm

內的牙數

螺距

P

外徑

D

厚度

E

1/8-40BSW

40

0.635

20

5

3/16-24BSW

24

1.058

7

3/16-32BSF

32

0.794

7/32-28BSF

28

0.907

1/4-20BSW

20

1.270

1/4-26BSF

26

0.977

9/32-26BSF

26

0.977

25

9

5/16-18BSW

18

1.411

5/16-22BSF

22

1.155

3/8-16BSW

16

1.588

30

11

3/8-20BSF

20

1.270

7/16-14BSW

14

1.814

7/16-18BSF

18

1.411

1/2-12BSW

12

2.117

38

14

1/2-16BSF

16

1.588

10

9/16-12BSW

12

2.117

14

9/16-16BSF

16

1.588

10

5/8-11BSW

11

2.309

45

14

5/8-14BSF

14

1.814

11/16-14BSF

14

1.814

3/4-10BSW

10

2.540

18

3/4-12BSF

12

2.117

14

7/8-9BSW

9

2.822

18

7/8-11BSF

11

2.309

1-8BSW

8

3.175

55

22

1-10BSF

10

2.540

1 1/8-7BSW

7

3.629

65

25

1 1/8-9BSF

9

2.822

1 1/4-7BSW

7

3.629

1 1/4-9BSF

9

2.822

1 1/2-6BSW

6

4.233

75

30

1 1/2-8BSF

8

3.175

1 3/4-5BSW

5

5.080

90

36

1 3/4-7BSF

7

3.629

2-4 1/2BSW

4 1/2

5.644

2-7BSF

7

3.629