2 General Information
2.1 Torque specifications for screws and nuts
Tightening torques for setscrew and connections as per MTN 5008 standard
The standard applies to setscrews and the associated nuts as specified in the following standards when
not subjected to dynamic loading:
• MMN 384
• DIN 912
• ISO 4014 (DIN 931-1)
• ISO 4017 (DIN 933)
• EN 28765 (DIN 960)
• EN 28676 (DIN 961)
• DIN 6912
The standard applies to studs and the associated nuts as specified in the following standards:
• DIN 833
• DIN 835
• DIN 836
• DIN 938
• DIN 939
The standard does not apply to heat-resistant screws in the hot-component area.
Tightening torques M
A
are specified for screws of strength class 8.8 (surface condition bare, phosphat-
ized or galvanized) and 10.9 (surface condition bare or phosphatized).
The values in the table are based on a friction coefficient µtot = 0.125.
Coat thread and mating faces of screws and nuts with engine oil prior to assembly.
An assembly tolerance of +10% of the table values is admissible when tightening manually (to specified
torque).
The admissible assembly tolerance is ±15% for machine tightening.
Thread
Hand-tightening
Machine-tightening
8.8 M
A
(Nm)
10.9 M
A
(Nm)
8.8 M
A
(Nm)
10.9 M
A
(Nm)
M6
9
12
8
11
M8
21
31
20
28
M8 x 1
23
32
21
30
M10
42
60
40
57
M10 x 1.25
45
63
42
60
M12
74
100
70
92
M12 x 1.25
80
110
75
105
M12 x 1.5
76
105
72
100
M14
115
160
110
150
M14 x 1.5
125
180
120
170
M16
180
250
170
235
M16 x 1.5
190
270
180
255
M18
250
350
240
330
M18 x 1.5
280
400
270
380
M20
350
500
330
475
MS150119/00E 2014-08
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