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STANDARD TIGHTENING TORQUES
SAE Grade 5 And Grade 8 Capscrews
The following specifications apply to required
assembly torques for all grade 5 and grade 8
capscrews.
NOTE: Capscrew threads and seats shall be
lubricated when assembled.
specifically recommend otherwise, these standard
torque values are to be used with simple lithium base
chassis grease (multi-purpose EP NLGI) or a rust-
preventive grease (see list, previous page) on the
threads.
NOTE: Torques are calculated to give a clamping
force of approximately 75% of proof load.
maximum torque tolerance shall be within ±10% of
the torque value shown.
In the following table under Capscrew Size, the first
number represents the shank diameter (in.).
second number represents threads per inch.
Example: 7/16 - 20
7/16 = shank diameter (7/16 inch (0.438 inch))
20 = threads per inch
Table 2-2
Standard Tightening Torque for SAE Hex
Head Capscrew And Nut Assembly
Cap-
Torque
screw
Grade 5
Size
N·m ft·lb kg·m N·m ft·lb kg·m
1/4-20
9.5
7
1/4-28
10.8
8
5/16-18
20.3
15
5/16-24
22
16
3/8-16
34
25
3/8-24
41
30
7/16-14
54
40
7/16-20
61
45
1/2-13
88
65
95
70
1/2-20
9/16-12
122
90
2-4
Unless instructions
The
The
Torque
Grade 8
0.97
13.6
10
1.38
1.11
14.9
11
1.52
2.07
28
21
2.90
2.21
30
22
3.04
3.46
47
35
4.84
5.5
4.15
54
40
5.5
79
58
8.0
6.2
84
62
8.57
9
122
90
12.4
9.7
129
95
13.1
12.4
169
125
17.3
STANDARD CHARTS AND TABLES
Standard Tightening Torque for SAE Hex
Head Capscrew And Nut Assembly
Cap-
Torque
screw
Grade 5
Size
N·m ft·lb kg·m N·m ft·lb kg·m
9/16-18
129
95
5/8-11
169
125
5/8-18
183
135
3/4-10
298
220
3/4-16
319
235
7/8-9
475
350
7/8-14
508
375
1.0-8
712
525
1.0-12
759
560
1.0-14
773
570
1 1/8-7
881
650
1 1/8-12
949
700
1 1/4-7
1234 910
1 1/4-12 1322 975
1 3/8-6
1627 1200
1 3/8-12 1776 1310
1 1/2-6
2142 1580
1 1/2-12 2305 1700
Torque
Grade 8
13.1
183
135
18.7
17.3
237
175
24.2
18.7
258
190
26.2
30.4
420
310
42.8
32.5
454
335
46.3
48.4
678
500
69.2
51.9
719
530
73.3
72.6
1017 750
103.7
77.4
1071 790
109.3
78.8
1085 800
110.6
89.9
1424 1050
145
96.8
1546 1140
158
125.9 2007 1480
205
134.8 2142 1580
219
166
2630 1940
268
181
2874 2120
293
219
3471 2560
354
235
3756 2770
383
830E-1AC
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