TIGHTENING TORQUE FOR SCREWS
30
9. TIGHTENING TORGUE FOR SCREWS
Tightening torque for galvanized screws
Strength
class
Tightening
torque
Nm
NOMINAL DIAMETER - NORMAL THREAD
M3
M4
M5
M6
M7
M8
M10
M12
M14
M16 M18
M20
M22
M24
M27 M30
M33 M36
M39
5.6
Nm
0.56
1.28 2.50
4.3
7.1
10.5
21
36
58
88
121
171
230
295
435
590
800 1030
1340
ft/lb
0.41
0.94
1.84
3.1
5.2
7.7
15
26
42
64
89
126
169
217
320
435
590
759
988
8.8
Nm
1.28
2.90
5.75
9.9
16.5
24
48
83
132
200
275
390
530
675
995 1350
1830
2360
3050
ft/lb
0.94
2.14
4.24
7.3
12.1
17.7
35
61
97
147
202
287
390
497
733
995
1349
1740
2249
10.9
Nm
1.80
4.10
8.1
14
23
34
67
117
185
285
390
550
745
960
1400 1900
2580
3310
4290
ft/lb
1.33
3.02
5.97
10.3
16.9
25
49
86.2
136
210
287
405
549
708
1032 1401
1902
2441
3163
12.9
Nm
2.15
4.95
9.70
16.5
27
40
81
140
220
340
470
660
890
1140 1680 2280 3090 3980
5150
ft/lb
1.59
3.65
7.15
12.1
19.9
29
59
103
162
250
346
486
656
840
1239 1681
2278
2935
3798
Strength
class
Tightening
torque
Nm
NOMINAL DIAMETER - FINE THREAD
M8 x 1
M10 x 1.25
M12 x 1.25
M14 x 1.5
M16 x 1.5
M18 x 1.5
M20 x 1.5
M22 x 1.5
M24 x 2
8.8
Nm
25
18
49
36
88
64
140
103
210
154
305
224
425
313
570
420
720
531
ft/lb
10.9
Nm
35
25
68
50
125
92
195
143
295
217
425
313
600
442
800
590
1000
737
ft/lb
12.9
Nm
42
30
82
60
150
110
235
173
350
258
510
376
720
531
960
708
1200
885
ft/lb
