67
Table for bolts tightening torque
Unit: N·
m
Bolt’s
diameter
Grade
4.6
5.6
6.6
8.8
6
4
~
5
5
~
7
6
~
8
9
~
12
8
10
~
12
12
~
15
14
~
18
22
~
29
10
20
~
25
25
~
31
29
~
39
44
~
58
12
35
~
44
44
~
54
49
~
64
76
~
107
14
54
~
69
69
~
88
83
~
98
121
~
162
16
88
~
108
108
~
137
127
~
157
189
~
252
18
118
~
147
147
~
186
176
~
216
260
~
347
20
167
~
206
206
~
265
245
~
314
369
~
492
22
225
~
284
284
~
343
343
~
431
502
~
669
24
294
~
370
370
~
441
441
~
539
638
~
850
27
441
~
519
539
~
686
637
~
784
933
~
1244
Note:
Use entirely 8.8 grade bolt in the important joint position.
Bolt‟s grade can be found in the head of the bolt, if it can‟t be found, the grade is 8.8.