ASME B18.2.2 (T-3)

Dimensional Standard of Hex Nut as per ASME B18.2.2 (T-3)

β = 15° to 30°
θ = 90° to 120°

Nominal Size

TPI

Unit

Width Across Flats

Width Across Corners

Thickness Hex Nut

Minor diameter (Bore)

Ran out of Bearing Face FIM

F

G

H

(d)

Specified Proof Load

Up to 150,000 psi

150,000 psi and Greater

Min.

Max.

Min.

Max.

Min.

Max.

Min.

Max.

Max.

1/4

0.25

20 UNC

Inch

0.428

0.438

0.488

0.505

0.212

0.226

0.196

0.207

0.015

0.010

mm

10.87

11.13

12.40

12.83

5.38

5.74

4.98

5.26

5/16

0.3125

18 UNC

Inch

0.489

0.500

0.557

0.577

0.258

0.273

0.252

0.265

0.016

0.011

mm

12.42

12.70

14.15

14.66

6.55

6.93

6.40

6.73

3/8

0.375

16 UNC

Inch

0.551

0.562

0.628

0.650

0.320

0.337

0.307

0.321

0.017

0.012

mm

14.00

14.27

15.95

16.51

8.13

8.56

7.80

8.15

7/16

0.4375

14 UNC

Inch

0.675

0.688

0.768

0.794

0.365

0.385

0.360

0.376

0.018

0.013

mm

17.15

17.48

19.51

20.17

9.27

9.78

9.14

9.55

1/2

0.5

13 UNC

Inch

0.736

0.750

0.840

0.866

0.427

0.448

0.417

0.434

0.019

0.014

mm

18.69

19.05

21.34

22.00

10.85

11.38

10.59

11.02

9/16

0.5625

12 UNC

Inch

0.861

0.875

0.982

1.010

0.473

0.496

0.472

0.490

0.020

0.015

mm

21.87

22.23

24.94

25.65

12.01

12.60

11.99

12.45

5/8

0.625

11 UNC

Inch

0.922

0.938

1.051

1.083

0.535

0.559

0.527

0.546

0.021

0.016

mm

23.42

23.83

26.70

27.51

13.59

14.20

13.39

13.87

3/4

0.75

10 UNC

Inch

1.088

1.125

1.240

1.299

0.617

0.665

0.642

0.663

0.023

0.018

mm

27.64

28.58

31.50

32.99

15.67

16.89

16.31

16.84

7/8

0.875

9 UNC

Inch

1.269

1.312

1.447

1.516

0.724

0.776

0.755

0.778

0.025

0.020

mm

32.23

33.32

36.75

38.51

18.39

19.71

19.18

19.76

1

1.000

8UNC

Inch

1.450

1.500

1.653

1.732

0.831

0.887

0.865

0.890

0.027

0.022

mm

36.83

38.10

41.99

43.99

21.11

22.53

21.97

22.61

1-1/8

1.125

8UN

Inch

1.631

1.688

1.859

1.949

0.939

0.999

0.990

1.015

0.030

0.025

mm

41.43

42.88

47.22

49.50

23.85

25.37

25.15

25.78

1-1/4

1.250

8UN

Inch

1.812

1.875

2.066

2.165

1.030

1.094

1.115

1.140

0.033

0.028

mm

46.02

47.63

52.48

54.99

26.16

27.79

28.32

28.96

1-3/8

1.375

8UN

Inch

1.994

2.062

2.273

2.382

1.138

1.206

1.240

1.265

0.036

0.031

mm

50.65

52.37

57.73

60.50

28.91

30.63

31.50

32.13

1-1/2

1.500

8UN

Inch

2.175

2.250

2.480

2.598

1.245

1.317

1.365

1.390

0.039

0.034

mm

55.25

57.15

62.99

65.99

31.62

33.45

34.67

35.31

1-5/8

1.625

8UN

Inch

2.350

2.430

2.679

2.805

1.364

1.416

1.490

1.515

0.044

0.038

mm

59.69

61.72

68.05

71.25

34.65

35.97

37.85

38.48

1-3/4

1.750

8UN

Inch

2.538

2.625

2.893

3.031

1.460

1.540

1.615

1.640

0.048

0.041

mm

64.47

66.68

73.48

76.99

37.08

39.12

41.02

41.66

1-7/8

1.875

8UN

Inch

2.722

2.813

3.103

3.247

1.567

1.651

1.740

1.765

0.051

0.044

mm

69.14

71.45

78.82

82.47

39.80

41.94

44.20

44.83

2

2.000

8UN

Inch

2.900

3.000

3.306

3.464

1.675

1.763

1.865

1.890

0.055

0.047

mm

73.66

76.20

83.97

87.99

42.55

44.78

47.37

48.01

2-1/4

2.250

8UN

Inch

3.263

3.375

3.719

3.897

1.890

1.986

2.115

2.140

0.061

0.052

mm

82.88

85.73

94.46

98.98

48.01

50.44

53.72

54.36

2-1/2

2.500

8UN

Inch

3.625

3.750

4.133

4.330

2.105

2.209

2.365

2.390

0.068

0.058

mm

92.08

95.25

104.98

109.98

53.47

56.11

60.07

60.71

2-3/4

2.750

8UN

Inch

3.988

4.125

4.546

4.763

2.319

2.431

2.615

2.640

0.074

0.064

mm

101.30

104.78

115.47

120.98

58.90

61.75

66.42

67.06

3

3.000

8UN

Inch

4.350

4.500

4.959

5.196

2.534

2.654

2.865

2.890

0.081

0.070

mm

110.49

114.30

125.96

131.98

64.36

67.41

72.77

73.41