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Bolt torque specs

Torque and clamp loads for grade 5 and 8 fasteners.

size

grade 5

grade 8

clamp (lbs)

Torque (ft-lbs)

clamp (lbs)

Torque (ft-lbs)

dry

oiled

dry

oiled

1/4-20

2000

8

6

2850

12

9

1/4-28

2300

10

7.5

3250

14

10

5/16-18

2250

17

13

4700

25

18

5/16-24

3700

19

14

5200

25

20

3/8-16

4950

30

23

7000

45

35

3/8-24

5600

35

25

7900

50

35

7/16-14

6800

50

35

9550

70

55

7/16-20

7600

55

40

10650

80

60

1/2-13

9000

75

55

12750

110

80

1/2-20

10250

90

65

14375

120

90

9/16-12

11600

110

80

16375

150

110

9/16-18

13000

120

90

18250

170

130

5/8-11

14400

150

110

20350

220

170

5/8-18

16375

180

130

23000

240

180

3/4-10

21300

260

200

30100

380

280

3/4-16

23800

300

220

33500

420

320

 


Copyright Knut Skoglund