ASME B18.2.2 (T-9)

Dimensional Standard of Heavy Hex Nut as per ASME B18.2.2 (T-9)

β = 15° to 30°
θ = 90° to 120°

Nominal Size

TPI

Width Across Flats

Width Across Corners

Thickness Hex Nut

Major diameter

Pitch diameter

Minor diameter

Ran out of Bearing Face FIM

F

G

H

(d)

(d)

(d)

Specified Proof Load

Up to 150,000 psi

150,000 psi and Greater

Min.

Max.

Min.

Max.

Min.

Max.

Min.

Min.

Max.

Min.

Max.

Max.

1/4

0.2500

20 UNC

Inch

0.488

0.500

0.556

0.577

0.218

0.250

0.250

0.218

0.222

0.196

0.207

0.017

0.011

mm

12.40

12.70

14.12

14.66

5.54

6.35

6.35

5.52

5.65

4.98

5.26

5/16

0.3125

18 UNC

Inch

0.546

0.562

0.622

0.650

0.280

0.314

0.313

0.276

0.282

0.252

0.265

0.020

0.012

mm

13.87

14.27

15.80

16.51

7.11

7.98

7.94

7.02

7.16

6.40

6.73

3/8

0.3750

16 UNC

Inch

0.669

0.688

0.763

0.794

0.341

0.377

0.375

0.334

0.340

0.307

0.321

0.021

0.014

mm

16.99

17.48

19.38

20.17

8.66

9.58

9.53

8.49

8.64

7.80

8.15

7/16

0.4375

14 UNC

Inch

0.728

0.750

0.830

0.866

0.403

0.441

0.438

0.391

0.397

0.360

0.376

0.022

0.015

mm

18.49

19.05

21.08

22.00

10.24

11.20

11.11

9.93

10.09

9.14

9.55

1/2

0.5000

13 UNC

Inch

0.850

0.875

0.969

1.010

0.464

0.504

0.500

0.450

0.457

0.417

0.434

0.023

0.016

mm

21.59

22.23

24.61

25.65

11.79

12.80

12.70

11.43

11.60

10.59

11.02

9/16

0.5625

12 UNC

Inch

0.909

0.938

1.037

1.083

0.526

0.568

0.563

0.508

0.515

0.472

0.490

0.024

0.017

mm

23.09

23.83

26.34

27.51

13.36

14.43

14.29

12.91

13.09

11.99

12.45

5/8

0.6250

11 UNC

Inch

1.031

1.062

1.175

1.227

0.587

0.631

0.625

0.566

0.573

0.527

0.546

0.025

0.018

mm

26.19

26.97

29.85

31.17

14.91

16.03

15.88

14.38

14.56

13.39

13.87

3/4

0.7500

10 UNC

Inch

1.212

1.250

1.382

1.443

0.710

0.758

0.750

0.685

0.693

0.642

0.663

0.027

0.020

mm

30.78

31.75

35.10

36.65

18.03

19.25

19.05

17.40

17.59

16.31

16.84

7/8

0.8750

9 UNC

Inch

1.394

1.438

1.589

1.660

0.833

0.885

0.875

0.803

0.811

0.755

0.778

0.029

0.022

mm

35.41

36.53

40.36

42.16

21.16

22.48

22.23

20.39

20.60

19.18

19.76

1

1.0000

8UNC

Inch

1.575

1.625

1.796

1.876

0.956

1.012

1.000

0.919

0.928

0.865

0.890

0.031

0.024

mm

40.01

41.28

45.62

47.65

24.28

25.70

25.40

23.34

23.56

21.97

22.61

1-1/8

1.1250

8UN

Inch

1.756

1.812

2.002

2.093

1.079

1.139

1.125

1.044

1.053

0.990

1.015

0.033

0.027

mm

44.60

46.02

50.85

53.16

27.41

28.93

28.58

26.51

26.74

25.15

25.78

1-1/4

1.2500

8UN

Inch

1.938

2.000

2.209

2.309

1.187

1.251

1.250

1.169

1.178

1.115

1.140

0.035

0.030

mm

49.23

50.80

56.11

58.65

30.15

31.78

31.75

29.69

29.92

28.32

28.96

1-3/8

1.3750

8UN

Inch

2.119

2.188

2.416

2.526

1.310

1.378

1.375

1.294

1.303

1.240

1.265

0.038

0.033

mm

53.82

55.58

61.37

64.16

33.27

35.00

34.93

32.86

33.10

31.50

32.13

1-1/2

1.5000

8UN

Inch

2.300

2.375

2.622

2.742

1.433

1.505

1.500

1.419

1.428

1.365

1.390

0.041

0.036

mm

58.42

60.33

66.60

69.65

36.40

38.23

38.10

36.04

36.28

34.67

35.31

1-5/8

1.6250

8UN

Inch

2.481

2.562

2.828

2.959

1.556

1.632

1.625

1.544

1.554

1.490

1.515

0.044

0.038

mm

63.02

65.07

71.83

75.16

39.52

41.45

41.28

39.21

39.46

37.85

38.48

1-3/4

1.7500

8UN

Inch

2.662

2.750

3.035

3.175

1.679

1.759

1.750

1.669

1.679

1.615

1.640

0.048

0.041

mm

67.61

69.85

77.09

80.65

42.65

44.68

44.45

42.39

42.64

41.02

41.66

1-7/8

1.8750

8UN

Inch

2.844

2.938

3.242

3.392

1.802

1.886

1.875

1.794

1.804

1.740

1.765

0.051

0.044

mm

72.24

74.63

82.35

86.16

45.77

47.90

47.63

45.56

45.82

44.20

44.83

2

2.0000

8UN

Inch

3.025

3.125

3.449

3.608

1.925

2.013

2.000

1.919

1.929

1.865

1.890

0.055

0.047

mm

76.84

79.38

87.60

91.64

48.90

51.13

50.80

48.74

48.99

47.37

48.01

2-1/4

2.2500

8UN

Inch

3.388

3.500

3.862

4.041

2.155

2.251

2.250

2.169

2.179

2.115

2.140

0.061

0.052

mm

86.06

88.90

98.09

102.64

54.74

57.18

57.15

55.09

55.35

53.72

54.36

2-1/2

2.5000

8UN

Inch

3.750

3.875

4.275

4.474

2.401

2.505

2.500

2.419

2.429

2.365

2.390

0.068

0.058

mm

95.25

98.43

108.59

113.64

60.99

63.63

63.50

61.44

61.71

60.07

60.71

2-3/4

2.7500

8UN

Inch

4.112

4.250

4.688

4.907

2.647

2.759

2.750

2.669

2.680

2.615

2.640

0.071

0.064

mm

104.44

107.95

119.08

124.64

67.23

70.08

69.85

67.79

68.06

66.42

67.06

3

3.0000

8UN

Inch

4.475

4.625

5.102

5.340

2.893

3.013

3.000

2.919

2.930

2.865

2.890

0.081

0.070

mm

113.67

117.48

129.59

135.64

73.48

76.53

76.20

74.14

74.42

72.77

73.41