螺丝攻牙钻孔径和滚造径对照表

公制粗螺纹

美制粗螺纹

规格

标准径

2级牙钻孔径

规格（UNC）

标准径

2级牙钻孔径

最大

最小

最大

最小

M1.0×0.25

0.75

0.785

0.729

NO.1-64(1.854)

1.55

1.582

1.425

M1.1×0.25

0.85

0.885

0.829

NO.2-56(2.184)

1.80

1.871

1.695

M1.2×0.25

0.95

0.985

0.985

NO.3-48(2.515)

2.10

2.146

1.941

M1.4×0.3

1.10

1.142

1.075

NO.4-40(2.845)

2.30

2.385

2.157

M1.6×0.35

1.25

1.321

1.221

NO.5-40(3.175)

2.60

2.697

2.487

M1.7×0.35

1.35

1.421

1.321

NO.6-32(3.505)

2.80

2.895

2.642

M1.8×0.35

1.45

1.521

1.421

NO8-32(4.166)

3.40

3.53

3.302

M2.0×0.4

1.60

1.679

1.567

NO.10-24(4.826)

3.90

3.962

3.683

M2.2×0.45

1.75

1.838

1.713

NO.12-24(5.486)

4.50

4.597

4.344

M2.3×0.4

1.90

1.979

1.867

1/4-20

5.10

5.257

4.979

M2.5×0.45

2.10

2.138

2.013

5/16-18

6.60

6.731

6.401

M2.6×0.45

2.20

2.238

2.113

3/8-16

8.00

8.153

7.798

M3.0×0.5

2.50

2.599

2.459

7/16-14

9.40

9.55

9.144

M3.0×0.6

2.40

2.440

2.280

1/2-13

10.80

11.023

10.592

M3.5×0.6

2.90

3.010

2.850

9/16-12

12.20

12.446

11.989

M4.0×0.7

3.30

3.422

3.242

5/8-11

13.60

12.868

13.386

M4.0×0.75

3.25

3.326

3.106

3/4-10

16.50

18.840

16.307

M4.5×0.75

3.80

3.878

3.688

7/8-9

19.50

19.761

19.177

M5.0×0.8

4.20

4.334

4.134

1

22.20

22.606

21.971

M5.0×0.9

4.10

4.170

3.930

1-1/8-7

25.00

25.349

24.638

M6.0×1.0

5.00

5.153

4.917

1-1/4-7

28.20

28.524

27.813

M7.0×1.0

6.00

6.153

5.917

1-3/8-6

30.80

31.115

30.353

M8.0×1.25

6.80

6.912

6.647

1-1/2-6

34.00

34.290

33.528

M9.0×1.25

7.80

7.912

7.647

1-3/4-5

39.50

39.827

38.964

M10×1.5

8.50

8.676

8.376

2-4-1/2

45.20

45.593

44.679

M11×1.5

9.50

9.676

9.376

M12×1.75

10.30

10.441

10.106

M14×2.0

12.00

12.210

11.835

M16×2.0

14.00

14.210

13.835

M18×2.5

15.50

15.744

15.294

M20×2.5

17.50

17.744

17.294

M22×2.5

19.50

19.744

19.294

M24×3.0

21.00

21.252

20.752

M27×3.0

24.00

24.252

23.752

M30×3.5

26.50

26.771

26.211