UNC threads

Thread

Number of threads per inch

Nominal
stress area mm²

Property class

4.8
415 N/mm²

5.8
510 N/mm²

8.8
827 N/mm²

10.9
1034 N/mm²

12.9
1239 N/mm²

1/4

20

20.5

8500

10450

16950

21200

25400

5/16

18

33.8

14000

17250

27950

34950

41900

3/8

16

50

20700

25500

41350

51700

62000

7/16

14

68.6

28400

34900

56750

70900

85100

1/2

13

91.5

37900

46700

75700

94600

113500

9/16

12

117

48400

59700

96800

121000

145100

5/8

11

146

60400

74400

120700

151000

181000

3/4

10

216

89400

110200

178600

223300

267800

7/8

9

298

123400

152000

246400

308100

369500

1

8

391

161900

199400

323400

404300

484800

1 1/8

7

492

203700

250900

406900

508700

610100

1 1/4

7

625

258700

318700

516900

646200

775000

1 3/8

6

745

308400

380000

616100

770030

923800

1 1/2

6

907

375500

462600

750100

937800

1124700

Thread

Number of threads per inch

Nominal
stress area mm²

Property class

4.8
248 N/mm²

5.8
393 N/mm²

8.8
634 N/mm²

10.9
896 N/mm²

12.9
1117 N/mm²

1/4

20

20.5

5080

8060

13000

18400

12900

5/16

18

33.8

8380

13300

21400

30300

37800

3/8

16

50

12400

19700

31700

44800

55900

7/16

14

68.6

17000

27000

43500

61500

76600

1/2

13

91.5

22700

36000

58000

82000

102000

9/16

12

117

29000

46000

74200

105000

131000

5/8

11

146

36200

57400

92600

131000

163000

3/4

10

216

53600

84900

137000

194000

241000

7/8

9

298

73900

11700

189000

267000

333000

1

8

391

97000

154000

248000

350000

437000

1 1/8

7

492

122000

193000

312000

441000

550000

1 1/4

7

625

155000

246000

396000

560000

698000

1 3/8

6

745

185000

293000

472000

667500

832000

1 1/2

6

907

225000

356000

575000

813000

10130000