5. About the engine
76
Note) The standard torque values above are about 70%
of the bolt elastic limit values.
Note) The tensile force has been calculated by multiplying
the tensile strength with the screw cross-sectional
area.
Note) A special screw should be tightened with 85% of
the tightening torque of the standard value. For
example, a MoS2-coated screw should be tightened
with 60% of the tightening torque of the standard
value.
2. Tightening Torque of Key General Bolts
M16 x
1.5
6.2
6.5
9.7
8.6
12.5
11.3
17
19.5
20
28
33
M18
7.8
8.3
12.5
11
16
14.5
21
24.2
25
36
43
M18 x
1.5
9.1
9.5
14.5
12.5
18.5
16.7
24.5
27.5
28
41
49
M20
11.5
12
18
16
22
19
31.5
35
36
51
60
M20 x
1.5
12.8
13.5
20.5
18
25
22.5
35
39.5
41
58
68
M22
15.5
16
24.5
21
30
26
42
46
49
67
75
M22 x
1.5
17
18.5
28
24
34
29
47
52
56
75
85
M24
20.5
21.5
33
27
40
34
55
58
63
82
92
M24 x
1.5
23
25
37
31
45
38
61
67
74
93
103
Nomi-
nal
Diame-
ter ×
Pitch
(mm)
Strength Classification
3.6
4.6
4.8
5.6
5.8
6.6
6.8
6.9
8.8
10.9
12.9
(4A)
(4D)
(4S)
(5D)
(5S)
(6D)
(6S)
(6G)
(8G)
(10K)
(12K)
Elastic Limit Value (kg/mm
2
)
20
24
32
30
40
36
46
54
64
90
106
Tightening Torque (kg
·
m)
Nominal Diameter x
Pitch (mm)
Strength Classification
Remarks
8.8T
10.9T
12.9T
Tightening Torque (kgf
·
m)
±
10%
M6 x 1
1
1.25
1.5
M8 x 1.25
2.2
3.1
3.8
M8 x 1
2.4
3.35
4.1
M10 x 1.5
4.4
6.2
7.4
M10 x 1.0
5
7
8.4
M12 x 1.75
7.5
10.5
12.5
M12 x 1.5
8
11.2
13.4
M14 x 1.5
13
18.5
22
