US Recommended Bolt Torque
Size |
Recommended Torque |
Grade 2 |
Grade 5 |
Grade 8 |
18-8 S/S |
Bronze |
Brass |
Coarse |
Fine |
Coarse |
Fine |
Coarse |
Fine |
Coarse |
Fine |
Coarse |
Fine |
Coarse |
Fine |
#4* |
- |
- |
- |
- |
- |
- |
5.2 |
- |
4.8 |
- |
4.3 |
- |
#6* |
- |
- |
- |
- |
- |
- |
9.6 |
- |
8.9 |
- |
7.9 |
- |
#8* |
- |
- |
- |
- |
- |
- |
19.8 |
- |
18.4 |
- |
16.2 |
- |
#10* |
- |
- |
- |
- |
- |
- |
22.8 |
31.7 |
21.2 |
29.3 |
18.6 |
25.9 |
1/4" |
4 |
4.7 |
6.3 |
7.3 |
9 |
10 |
6.3 |
7.8 |
5.7 |
7.3 |
5.1 |
6.4 |
5/16" |
8 |
9 |
13 |
14 |
18 |
20 |
11 |
11.8 |
10.3 |
10.9 |
8.9 |
9.7 |
3/8" |
15 |
17 |
23 |
26 |
33 |
37 |
20 |
22 |
18 |
20 |
16 |
18 |
7/16" |
24 |
27 |
37 |
41 |
52 |
58 |
31 |
33 |
29 |
31 |
26 |
27 |
1/2" |
37 |
41 |
57 |
64 |
80 |
90 |
43 |
45 |
40 |
42 |
35 |
37 |
9/16" |
53 |
59 |
82 |
91 |
115 |
129 |
57 |
63 |
53 |
58 |
47 |
51 |
5/8" |
73 |
83 |
112 |
128 |
159 |
180 |
93 |
104 |
86 |
96 |
76 |
85 |
3/4" |
125 |
138 |
200 |
223 |
282 |
315 |
128 |
124 |
104 |
102 |
118 |
115 |
7/8" |
129 |
144 |
322 |
355 |
454 |
501 |
194 |
193 |
178 |
178 |
159 |
158 |
1"† |
188 |
210 |
483 |
541 |
682 |
764 |
287 |
289 |
265 |
240 |
235 |
212 |
* Sizes from #4 to #10 are in lb-in.
Sizes from 1/4" up are in lb-ft.
† Fine thread figures are for 1"-14.
Grade 2, 5, and 8 values are for slightly lubricated bolts. |